Ame Ame provides a simple command-line interface API for Ruby¹. It can be used to provide both simple interfaces like that of ‹rm›² and complex ones like that of ‹git›³. It uses Ruby’s own classes, methods, and argument lists to provide an interface that is both simple to use from the command-line side and from the Ruby side. The provided command-line interface is flexible and follows commond standards for command-line processing. ¹ See http://ruby-lang.org/ ² See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/rm.html ³ See http://git-scm.com/docs/ § Usage Let’s begin by looking at two examples, one where we mimic the POSIX¹ command-line interface to the ‹rm› command. Looking at the entry² in the standard, ‹rm› takes the following options: = -f. = Do not prompt for confirmation. = -i. = Prompt for confirmation. = -R. = Remove file hierarchies. = -r. = Equivalent to /-r/. It also takes the following arguments: = FILE. = A pathname or directory entry to be removed. And actually allows one or more of these /FILE/ arguments to be given. We also note that the ‹rm› command is described as a command to “remove directory entries”. ¹ See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/contents.html ² See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/rm.html Let’s turn this specification into one using Ame’s API. We begin by adding a flag for each of the options listed above: class Rm < Ame::Root flag 'f', '', false, 'Do not prompt for confirmation' flag 'i', '', nil, 'Prompt for confirmation' do |options| options['f'] = false end flag 'R', '', false, 'Remove file hierarchies' flag 'r', '', nil, 'Equivalent to -R' do |options| options['r'] = true end A flag¹ is a boolean option that doesn’t take an argument. Each flag gets a short and long name, where an empty name means that there’s no corresponding short or long name for the flag, a default value (true, false, or nil), and a description of what the flag does. Each flag can also optionally take a block that can do further processing. In this case we use this block to modify the Hash that maps option names to their values passed to the block to set other flags’ values than the ones that the block is associated with. As these flags (‘i’ and ‘r’) aren’t themselves of interest, their default values have been set to nil, which means that they won’t be included in the Hash that maps option names to their values when passed to the method. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#flag-class-method There are quite a few other kinds of options besides flags that can be defined using Ame, but flags are all that are required for this example. We’ll get to the other kinds in later examples. Next we add a “splus” argument. splus 'FILE', String, 'File to remove' A splus¹ argument is like a Ruby “splat”, that is, an Array argument at the end of the argument list to a method preceded by a star, except that a splus requires at least one argument. A splus argument gets a name for the argument (‹FILE›), the type of argument it represents (String), and a description. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#splus-class-method Then we add a description of the command (method) itself: description 'Remove directory entries' Descriptions¹ will be used in help output to assist the user in using the command. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#description-class-method Finally, we add the Ruby method that’ll implement the command (all preceding code included here for completeness): class Rm < Ame::Root version '1.0.0' flag 'f', '', false, 'Do not prompt for confirmation' flag 'i', '', nil, 'Prompt for confirmation' do |options| options['f'] = false end flag 'R', '', false, 'Remove file hierarchies' flag 'r', '', nil, 'Equivalent to -R' do |options| options['r'] = true end splus 'FILE', String, 'File to remove' description 'Remove directory entries' def rm(files, options = {}) require 'fileutils' FileUtils.send options['R'] ? :rm_r : :rm, [first] + rest, :force => options['f'] end end Actually, another bit of code was also added, namely version '1.0.0' This sets the version¹ String of the command. This information is used when the command is invoked with the “‹--version›” flag. This flag is automatically added, so you don’t need to add it yourself. Another flag, “‹--help›”, is also added automatically. When given, this flag’ll make Ame output usage information of the command. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#version-class-method To actually run the command, all you need to do is invoke Rm.process This’ll invoke the command using the command-line arguments stored in ‹ARGV›, but you can also specify other ones if you want to: Rm.process 'rm', %w[-r /tmp/*] The first argument to #process¹ is the name of the method to invoke, which defaults to ‹File.basename($0)›, and the second argument is an Array of Strings that should be processed as command-line arguments passed to the command. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#process-class-method If you’d store the complete ‹Rm› class defined above in a file called ‹rm› and add ‹#! /usr/bin/ruby -w› at the beginning and ‹Rm.process› at the end, you’d have a fully functional ‹rm› command (after making it executable). Let’s see it in action: % rm --help Usage: rm [OPTIONS]... FILE... Remove directory entries Arguments: FILE... File to remove Options: -R Remove file hierarchies -f Do not prompt for confirmation --help Display help for this method -i Prompt for confirmation -r Equivalent to -R --version Display version information % rm --version rm 1.0.0 Some commands are more complex than ‹rm›. For example, ‹git›¹ has a rather complex command-line interface. We won’t mimic it all here, but let’s introduce the rest of the Ame API using a fake ‹git› clone as an example. ¹ See http://git-scm.com/docs/ ‹Git› uses sub-commands to achieve most things. Implementing sub-commands with Ame is done using a “dispatch”. We’ll discuss dispatches in more detail later, but suffice it to say that a dispatch delegates processing to a child class that’ll handle the sub-command in question. We begin by defining our main ‹git› command using a class called ‹Git› under the ‹Git::CLI› namespace: module Git end class Git::CLI < Ame::Root version '1.0.0' class Git < Ame::Class description 'The stupid content tracker' def initialize; end We’re setting things up to use the ‹Git› class as a dispatch in the ‹Git::CLI› class. The description on the ‹initialize› method will be used as a description of the ‹git› dispatch command itself. Next, let’s add the ‹format-patch›¹ sub-command: description 'Prepare patches for e-mail submission' flag ?n, 'numbered', false, 'Name output in [PATCH n/m] format' flag ?N, 'no-numbered', nil, 'Name output in [PATCH] format' do |options| options['numbered'] = false end toggle ?s, 'signoff', false, 'Add Signed-off-by: line to the commit message' switch '', 'thread', 'STYLE', nil, Ame::Types::Enumeration[:shallow, :deep], 'Controls addition of In-Reply-To and References headers' flag '', 'no-thread', nil, 'Disables addition of In-Reply-To and Reference headers' do |options, _| options.delete 'thread' end option '', 'start-number', 'N', 1, 'Start numbering the patches at N instead of 1' multioption '', 'to', 'ADDRESS', String, 'Add a To: header to the email headers' optional 'SINCE', 'N/A', 'Generate patches for commits after SINCE' def format_patch(since = '', options = {}) p since, options end ¹ See http://git-scm.com/docs/git-format-patch/ We’re using quite a few new Ame commands here. Let’s look at each in turn: toggle ?s, 'signoff', false, 'Add Signed-off-by: line to the commit message' A “toggle”¹ is a flag that also has an inverse. Beyond the flags ‘s’ and “signoff”, the toggle also defines “no-signoff”, which will set “signoff” to false. This is useful if you want to support configuration files that set “signoff”’s default to true, but still allow it to be overridden on the command line. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#toggle-class-method When using the short form of a toggle (and flag and switch), multiple ones may be juxtaposed after the initial one. For example, “‹-sn›” is equivalent to “‹-s -n›” to “git format-patch›”. switch '', 'thread', 'STYLE', nil, Ame::Types::Enumeration[:shallow, :deep], 'Controls addition of In-Reply-To and References headers' A “switch”¹ is an option that takes an optional argument. This allows you to have separate defaults for when the switch isn’t present on the command line and for when it’s given without an argument. The third argument to a switch is the name of the argument. We’re also introducing a new concept here in ‹Ame::Types::Enumeration›. An enumeration² allows you to limit the allowed input to a set of Symbols. An enumeration also has a default value in the first item to its constructor (which is aliased as ‹.[]›). In this case, the “thread” switch defaults to nil, but, when given, will default to ‹:shallow› if no argument is given. If an argument is given it must be either “shallow” or “deep”. A switch isn’t required to take an enumeration as its argument default and can take any kind of default value for its argument that Ame knows how to handle. We’ll look at this in more detail later, but know that the type of the default value will be used to inform Ame how to parse a command-line argument into a Ruby value. An argument to a switch must be given, in this case, as “‹--thread=deep›” on the command line. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#switch-class-method ² See http://disu.se/software/ame-1.0/api/user/Ame/Types/Enumeration/ option '', 'start-number', 'N', 1, 'Start numbering the patches at N instead of 1' An “option”¹ is an option that takes an argument. The argument must always be present and may be given, in this case, as “‹--start-number=2›” or “‹--start-number 2›” on the command line. For a short-form option, anything that follows the option is seen as an argument, so assuming that “start-number” also had a short name of ‘S’, “‹-S2›” would be equivalent to “‹-S 2›”, which would be equivalent to “‹--start-number 2›”. Note that “‹-snS2›” would still work as expected. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#option-class-method multioption '', 'to', 'ADDRESS', String, 'Add a To: header to the email headers' A “multioption”¹ is an option that takes an argument and may be repeated any number of times. Each argument will be added to an Array stored in the Hash that maps option names to their values. Instead of taking a default argument, it takes a type for the argument (String, in this case). Again, types are used to inform Ame how to parse command-line arguments into Ruby values. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#multioption-class-method optional 'SINCE', 'N/A', 'Generate patches for commits after SINCE' An “optional”¹ argument is an argument that isn’t required. If it’s not present on the command line it’ll get its default value (the String ‹'N/A'›, in this case). ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#optional-class-method We’ve now covered all kinds of options and one new kind of argument. There are three more types of argument (one that we’ve already seen and two new) that we’ll look into now: “argument”, “splat”, and “splus”. description 'Annotate file lines with commit information' argument 'FILE', String, 'File to annotate' def annotate(file) p file end An “argument”¹ is an argument that’s required. If it’s not present on the command line, an error will be raised (and by default reported to the terminal). As it’s required, it doesn’t take a default, but rather a type. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#argument-class-method description 'Add file contents to the index' splat 'PATHSPEC', String, 'Files to add content from' def add(paths) p paths end A “splat”¹ is an argument that’s not required, but may be given any number of times. The type of a splat is the type of one argument and the type of a splat as a whole is an Array of values of that type. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#splat-class-method description 'Display gitattributes information' splus 'PATHNAME', String, 'Files to list attributes of' def check_attr(paths) p paths end A “splus”¹ is an argument that’s required, but may also be given any number of times. The type of a splus is the type of one argument and the type of a splus as a whole is an Array of values of that type. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#splus-class-method Now that we’ve seen all kinds of options and arguments, let’s look on an additional tool at our disposal, the dispatch¹. class Remote < Ame::Class description 'Manage set of remote repositories' def initialize; end description 'Shows a list of existing remotes' flag 'v', 'verbose', false, 'Show remote URL after name' def list(options = {}) p options end description 'Adds a remote named NAME for the repository at URL' argument 'name', String, 'Name of the remote to add' argument 'url', String, 'URL to the repository of the remote to add' def add(name, url) p name, url end end ¹ See http://disu.se/software/ame-1.0/api/user/Ame/Class#dispatch-class-method Here we’re defining a child class to Git::CLI::Git called “Remote” that doesn’t introduce anything new. Then we set up the dispatch: dispatch Remote, :default => 'list' This adds a method called “remote” to Git::CLI::Git that will dispatch processing of the command line to an instance of the Remote class when “‹git remote›” is seen on the command line. The “remote” method expects an argument that’ll be used to decide what sub-command to execute. Here we’ve specified that in the absence of such an argument, the “list” method should be invoked. We add the same kind of dispatch to Git under Git::CLI: dispatch Git and then we’re done. Here’s all the previous code in its entirety: module Git end class Git::CLI < Ame::Root version '1.0.0' class Git < Ame::Class description 'The stupid content tracker' def initialize; end description 'Prepare patches for e-mail submission' flag ?n, 'numbered', false, 'Name output in [PATCH n/m] format' flag ?N, 'no-numbered', nil, 'Name output in [PATCH] format' do |options| options['numbered'] = false end toggle ?s, 'signoff', false, 'Add Signed-off-by: line to the commit message' switch '', 'thread', 'STYLE', nil, Ame::Types::Enumeration[:shallow, :deep], 'Controls addition of In-Reply-To and References headers' flag '', 'no-thread', nil, 'Disables addition of In-Reply-To and Reference headers' do |options, _| options.delete 'thread' end option '', 'start-number', 'N', 1, 'Start numbering the patches at N instead of 1' multioption '', 'to', 'ADDRESS', String, 'Add a To: header to the email headers' optional 'SINCE', 'N/A', 'Generate patches for commits after SINCE' def format_patch(since = '', options = {}) p since, options end description 'Annotate file lines with commit information' argument 'FILE', String, 'File to annotate' def annotate(file) p file end description 'Add file contents to the index' splat 'PATHSPEC', String, 'Files to add content from' def add(paths) p paths end description 'Display gitattributes information' splus 'PATHNAME', String, 'Files to list attributes of' def check_attr(paths) p paths end class Remote < Ame::Class description 'Manage set of remote repositories' def initialize; end description 'Shows a list of existing remotes' flag 'v', 'verbose', false, 'Show remote URL after name' def list(options = {}) p options end description 'Adds a remote named NAME for the repository at URL' argument 'name', String, 'Name of the remote to add' argument 'url', String, 'URL to the repository of the remote to add' def add(name, url) p name, url end end dispatch Remote, :default => 'list' end dispatch Git end If we put this code in a file called “git” and add ‹#! /usr/bin/ruby -w› at the beginning and ‹Git::CLI.process› at the end, you’ll have a very incomplete git command-line interface on your hands. Let’s look at what some of its ‹--help› output looks like: % git --help Usage: git [OPTIONS]... METHOD [ARGUMENTS]... The stupid content tracker Arguments: METHOD Method to run [ARGUMENTS]... Arguments to pass to METHOD Options: --help Display help for this method --version Display version information Methods: add Add file contents to the index annotate Annotate file lines with commit information check-attr Display gitattributes information format-patch Prepare patches for e-mail submission remote Manage set of remote repositories % git format-patch --help Usage: git format-patch [OPTIONS]... [SINCE] Prepare patches for e-mail submission Arguments: [SINCE=N/A] Generate patches for commits after SINCE Options: -N, --no-numbered Name output in [PATCH] format --help Display help for this method -n, --numbered Name output in [PATCH n/m] format --no-thread Disables addition of In-Reply-To and Reference headers -s, --signoff Add Signed-off-by: line to the commit message --start-number=N Start numbering the patches at N instead of 1 --thread[=STYLE] Controls addition of In-Reply-To and References headers --to=ADDRESS* Add a To: header to the email headers % git remote --help Usage: git remote [OPTIONS]... [METHOD] [ARGUMENTS]... Manage set of remote repositories Arguments: [METHOD=list] Method to run [ARGUMENTS]... Arguments to pass to METHOD Options: --help Display help for this method Methods: add Adds a remote named NAME for the repository at URL list Shows a list of existing remotes § API The previous section gave an introduction to the whole user API in an informal and introductory way. For an indepth reference to the user API, see the {user API documentation}¹. ¹ See http://disu.se/software/ame-1.0/api/user/Ame/ If you want to extend the API or use it in some way other than as a command-line-interface writer, see the {developer API documentation}¹. ¹ See http://disu.se/software/ame-1.0/api/developer/Ame/ § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=now@disu.se&item_name=Ame § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/ame/issues § Authors Nikolai Weibull wrote the code, the tests, the documentation, and this README. § Licensing Ame is free software: you may redistribute it and/or modify it under the terms of the {GNU Lesser General Public License, version 3}¹ or later², as published by the {Free Software Foundation}³. ¹ See http://disu.se/licenses/lgpl-3.0/ ² See http://gnu.org/licenses/ ³ See http://fsf.org/

Inventory Inventory keeps track of the contents of your Ruby¹ projects. Such an inventory can be used to load the project, create gem specifications and gems, run unit tests, compile extensions, and verify that the project’s content is what you think it is. ¹ See http://ruby-lang.org/ § Usage Let’s begin by discussing the project structure that Inventory expects you to use. It’s pretty much exactly the same as the standard Ruby project structure¹: ├── README ├── Rakefile ├── lib │ ├── foo-1.0 │ │ ├── bar.rb │ │ └── version.rb │ └── foo-1.0.rb └── test └── unit ├── foo-1.0 │ ├── bar.rb │ └── version.rb └── foo-1.0.rb Here you see a simplified version of a project called “Foo”’s project structure. The only real difference from the standard is that the main entry point into the library is named “foo-1.0.rb” instead of “foo.rb” and that the root sub-directory of “lib” is similarly named “foo-1.0” instead of “foo”. The difference is the inclusion of the API version. This must be the major version of the project followed by a constant “.0”. The reason for this is that it allows concurrent installations of different major versions of the project and means that the wrong version will never accidentally be loaded with require. There’s a bigger difference in the content of the files. ‹Lib/foo-1.0/version.rb› will contain our inventory instead of a String: require 'inventory-1.0' class Foo Version = Foo.new(1, 4, 0){ authors{ author 'A. U. Thor', 'a.u.thor@example.org' } homepage 'http://example.org/' licenses{ license 'LGPLv3+', 'GNU Lesser General Public License, version 3 or later', 'http://www.gnu.org/licenses/' } def dependencies super + Dependencies.new{ development 'baz', 1, 3, 0 runtime 'goo', 2, 0, 0 optional 'roo-loo', 3, 0, 0, :feature => 'roo-loo' } end def package_libs %w[bar.rb] end } end We’re introducing quite a few concepts at once, and we’ll look into each in greater detail, but we begin by setting the ‹Version› constant to a new instance of an Inventory with major, minor, and patch version atoms 1, 4, and 0. Then we add a couple of dependencies and list the library files that are included in this project. The version numbers shouldn’t come as a surprise. These track the version of the API that we’re shipping using {semantic versioning}². They also allow the Inventory#to_s method to act as if you’d defined Version as ‹'1.4.0'›. Next follows information about the authors of the project, the project’s homepage, and the project’s licenses. Each author has a name and an email address. The homepage is simply a string URL. Licenses have an abbreviation, a name, and a URL where the license text can be found. We then extend the definition of ‹dependencies› by adding another set of dependencies to ‹super›. ‹Super› includes a dependency on the version of the inventory project that’s being used with this project, so you’ll never have to list that yourself. The other three dependencies are all of different kinds: development, runtime, and optional. A development dependency is one that’s required while developing the project, for example, a unit-testing framework, a documentation generator, and so on. Runtime dependencies are requirements of the project to be able to run, both during development and when installed. Finally, optional dependencies are runtime dependencies that may or may not be required during execution. The difference between runtime and optional is that the inventory won’t try to automatically load an optional dependency, instead leaving that up to you to do when and if it becomes necessary. By that logic, runtime dependencies will be automatically loaded, which is a good reason for having dependency information available at runtime. The version numbers of dependencies also use semantic versioning, but note that the patch atom is ignored unless the major atom is 0. You should always only depend on the major and minor atoms. As mentioned, runtime dependencies will be automatically loaded and the feature they try to load is based on the name of the dependency with a “-X.0” tacked on the end, where ‘X’ is the major version of the dependency. Sometimes, this isn’t correct, in which case the :feature option may be given to specify the name of the feature. You may also override other parts of a dependency by passing in a block to the dependency, much like we’re doing for inventories. The rest of an inventory will list the various files included in the project. This project only consists of one additional file to those that an inventory automatically include (Rakefile, README, the main entry point, and the version.rb file that defines the inventory itself), namely the library file ‹bar.rb›. Library files will be loaded automatically when the main entry point file loads the inventory. Library files that shouldn’t be loaded may be listed under a different heading, namely “additional_libs”. Both these sets of files will be used to generate a list of unit test files automatically, so each library file will have a corresponding unit test file in the inventory. We’ll discuss the different headings of an inventory in more detail later on. Now that we’ve written our inventory, let’s set it up so that it’s content gets loaded when our main entry point gets loaded. We add the following piece of code to ‹lib/foo-1.0.rb›: module Foo load File.expand_path('../foo-1.0/version.rb', __FILE__) Version.load end That’s all there’s to it. The inventory can also be used to great effect from a Rakefile using a separate project called Inventory-Rake³. Using it’ll give us tasks for cleaning up our project, compiling extensions, installing dependencies, installing and uninstalling the project itself, and creating and pushing distribution files to distribution points. require 'inventory-rake-1.0' load File.expand_path('../lib/foo-1.0/version.rb', __FILE__) Inventory::Rake::Tasks.define Foo::Version Inventory::Rake::Tasks.unless_installing_dependencies do require 'lookout-rake-3.0' Lookout::Rake::Tasks::Test.new end It’s ‹Inventory::Rake::Tasks.define› that does the heavy lifting. It takes our inventory and sets up the tasks mentioned above. As we want to be able to use our Rakefile to install our dependencies for us, the rest of the Rakefile is inside the conditional #unless_installing_dependencies, which, as the name certainly implies, executes its block unless the task being run is the one that installs our dependencies. This becomes relevant when we set up Travis⁴ integration next. The only conditional set-up we do in our Rakefile is creating our test task via Lookout-Rake⁵, which also uses our inventory to find the unit tests to run when executed. Travis integration is straightforward. Simply put before_script: - gem install inventory-rake -v '~> VERSION' --no-rdoc --no-ri - rake gem:deps:install in the project’s ‹.travis.yml› file, replacing ‹VERSION› with the version of Inventory-Rake that you require. This’ll make sure that Travis installs all development, runtime, and optional dependencies that you’ve listed in your inventory before running any tests. You might also need to put env: - RUBYOPT=rubygems in your ‹.travis.yml› file, depending on how things are set up. ¹ Ruby project structure: http://guides.rubygems.org/make-your-own-gem/ ² Semantic versioning: http://semver.org/ ³ Inventory-Rake: http://disu.se/software/inventory-rake-1.0/ ⁴ Travis: http://travis-ci.org/ ⁵ Lookout-Rake: http://disu.se/software/lookout-rake-3.0/ § API If the guide above doesn’t provide you with all the answers you seek, you may refer to the API¹ for more answers. ¹ See http://disu.se/software/inventory-1.0/api/Inventory/ § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=now@disu.se&item_name=Inventory § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/inventory/issues § Authors Nikolai Weibull wrote the code, the tests, the documentation, and this README. § Licensing Inventory is free software: you may redistribute it and/or modify it under the terms of the {GNU Lesser General Public License, version 3}¹ or later², as published by the {Free Software Foundation}³. ¹ See http://disu.se/licenses/lgpl-3.0/ ² See http://gnu.org/licenses/ ³ See http://fsf.org/

Inventory-Rake Inventory-Rake provides Rake¹ tasks for your Inventory². This includes tasks for cleaning up our project, compiling extensions, installing dependencies, installing and uninstalling the project itself, and creating and pushing distribution files to distribution points. ¹ See http://rake.rubyforge.org/ ² See http://disu.se/software/inventory-1.0/ § Installation Install Inventory-Rake with % gem install inventory-rake § Usage Include the following code in your ‹Rakefile›, where ‹Package› is the top-level module of your project: require 'inventory-rake-3.0' load File.expand_path('../lib/package/version.rb', __FILE__) Inventory::Rake::Tasks.define Package::Version Inventory::Rake::Tasks.unless_installing_dependencies do # Any additional tasks that your project’s dependencies provide end ‹Inventory::Rake::Tasks.define› does the heavy lifting. It takes our inventory and sets up the tasks mentioned above. We also do some additional customization of the gem specification. As we want to be able to use our Rakefile to install our dependencies for us, the rest of the Rakefile is inside the conditional #unless_installing_dependencies, which, as the name certainly implies, executes its block unless the task being run is the one that installs our dependencies. This becomes relevant if we want to, for example, set up Travis¹ integration. To do so, simply add before_script: - gem install inventory-rake -v '~> VERSION' --no-rdoc --no-ri - rake gem:deps:install to your ‹.travis.yml› file. This’ll make sure that Travis installs all development, runtime, and optional dependencies that you’ve listed in your inventory before running any tests. There’s more information in the {API documentation}² that you’ll likely want to read up on if anything is unclear. ¹ See http://travis-ci.org/ ² See http://disu.se/software/inventory-rake-1.0/api/Inventory/Rake/ § Tasks The tasks that are created if you use Inventory-Rake are: = check. = Check that the package meets its expectations. = mostlyclean. = Delete targets built by rake that are ofter rebuilt. = clean. = Delete targets built by rake; depends on mostlyclean. = distclean. = Delete all files not meant for distribution; depends on clean. = compile. = Compile all extensions; depends on each compile:name. = compile:name. = Compile extension /name/; depends on lib/path/so file. = lib/path/so. = Installed dynamic library of extension /name/ inside inventory path; depends on ext/name/so. = ext/name/so. = Dynamic library of extension /name/; depends on ext/name/Makefile and the source files of the extension. = ext/name/Makefile. = Makefile for extension /name/; depends on inventory path, ext/name/extconf.rb file, and ext/name/depend file. Will be created by extconf.rb, which may take options from environment variable name#upcase_EXTCONF_OPTIONS or ‹EXTCONF_OPTIONS› if defined. = clean:name. = Clean files built for extension /name/; depended upon by clean. = spec. = Create specifications; depends on gem:spec. = gem:spec. = Create gem specification; depends on gemspec. = gemspec (file). = Gem specification file; depends on Rakefile, README, and inventory path. = dist. = Create files for distribution; depends on gem:dist. = gem:dist. = Create gem for distribution; depends on inventory:check and gem file. = inventory:check. = Check that the inventory is correct by looking for files not listed in the inventory that match the pattern and for files listed in the inventory that don’t exist; depends on distclean. = gem (file). = Gem file; depends on files included in gem. = dist:check. = Check files before distribution; depends on dist and gem:dist:check. = gem:dist:check. = Check gem before distribution; depends on gem:dist. = deps:install. = Install dependencies on the local system; depends on gem:deps:install. = gem:deps:install. = Install dependencies in ruby gem directory. = deps:install:user. = Install dependencies for the current user; depends on gem:deps:install:user. = gem:deps:install:user. = Install dependencies in the user gem directory. = install. = Install distribution files on the local system; depends on gem:install. = gem:install. = Install gem in ruby gem directory; depends on gem:dist. = install:user. = Install distribution files for the current user; depends on gem:install:user. = gem:install:user. = Install gem in the user gem directory. = uninstall. = Delete all files installed on the local system. = gem:uninstall. = Uninstall gem from ruby gem directory. = uninstall:user. = Delete all files installed for current user. = gem:uninstall:user. = Uninstall gem from ruby gem directory. = push. = Push distribution files to distribution hubs. = gem:push. = Push gem to rubygems.org. § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=now@disu.se&item_name=Inventory-Rake § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/inventory-rake/issues § Authors Nikolai Weibull wrote the code, the tests, the manual pages, and this README. § Licensing Inventory-Rake is free software: you may redistribute it and/or modify it under the terms of the {GNU Lesser General Public License, version 3}¹ or later², as published by the {Free Software Foundation}³. ¹ See http://disu.se/licenses/lgpl-3.0/ ² See http://gnu.org/licenses/ ³ See http://fsf.org/

Lookout Lookout is a unit testing framework for Ruby¹ that puts your results in focus. Tests (expectations) are written as follows expect 2 do 1 + 1 end expect ArgumentError do Integer('1 + 1') end expect Array do [1, 2, 3].select{ |i| i % 2 == 0 } end expect [2, 4, 6] do [1, 2, 3].map{ |i| i * 2 } end Lookout is designed to encourage – force, even – unit testing best practices such as • Setting up only one expectation per test • Not setting expectations on non-public APIs • Test isolation This is done by • Only allowing one expectation to be set per test • Providing no (additional) way of accessing private state • Providing no setup and tear-down methods, nor a method of providing test helpers Other important points are • Putting the expected outcome of a test in focus with the steps of the calculation of the actual result only as a secondary concern • A focus on code readability by providing no mechanism for describing an expectation other than the code in the expectation itself • A unified syntax for setting up both state-based and behavior-based expectations The way Lookout works has been heavily influenced by expectations², by {Jay Fields}³. The code base was once also heavily based on expectations, based at Subversion {revision 76}⁴. A lot has happened since then and all of the work past that revision are due to {Nikolai Weibull}⁵. ¹ Ruby: http://ruby-lang.org/ ² Expectations: http://expectations.rubyforge.org/ ³ Jay Fields’s blog: http://blog.jayfields.com/ ⁴ Lookout revision 76: https://github.com/now/lookout/commit/537bedf3e5b3eb4b31c066b3266f42964ac35ebe ⁵ Nikolai Weibull’s home page: http://disu.se/ § Installation Install Lookout with % gem install lookout § Usage Lookout allows you to set expectations on an object’s state or behavior. We’ll begin by looking at state expectations and then take a look at expectations on behavior. § Expectations on State: Literals An expectation can be made on the result of a computation: expect 2 do 1 + 1 end Most objects, in fact, have their state expectations checked by invoking ‹#==› on the expected value with the result as its argument. Checking that a result is within a given range is also simple: expect 0.099..0.101 do 0.4 - 0.3 end Here, the more general ‹#===› is being used on the ‹Range›. § Regexps ‹Strings› of course match against ‹Strings›: expect 'ab' do 'abc'[0..1] end but we can also match a ‹String› against a ‹Regexp›: expect %r{a substring} do 'a string with a substring' end (Note the use of ‹%r{…}› to avoid warnings that will be generated when Ruby parses ‹expect /…/›.) § Modules Checking that the result includes a certain module is done by expecting the ‹Module›. expect Enumerable do [] end This, due to the nature of Ruby, of course also works for classes (as they are also modules): expect String do 'a string' end This doesn’t hinder us from expecting the actual ‹Module› itself: expect Enumerable do Enumerable end or the ‹Class›: expect String do String end for obvious reasons. As you may have figured out yourself, this is accomplished by first trying ‹#==› and, if it returns ‹false›, then trying ‹#===› on the expected ‹Module›. This is also true of ‹Ranges› and ‹Regexps›. § Booleans Truthfulness is expected with ‹true› and ‹false›: expect true do 1 end expect false do nil end Results equaling ‹true› or ‹false› are slightly different: expect TrueClass do true end expect FalseClass do false end The rationale for this is that you should only care if the result of a computation evaluates to a value that Ruby considers to be either true or false, not the exact literals ‹true› or ‹false›. § IO Expecting output on an IO object is also common: expect output("abc\ndef\n") do |io| io.puts 'abc', 'def' end This can be used to capture the output of a formatter that takes an output object as a parameter. § Warnings Expecting warnings from code isn’t very common, but should be done: expect warning('this is your final one!') do warn 'this is your final one!' end expect warning('this is your final one!') do warn '%s:%d: warning: this is your final one!' % [__FILE__, __LINE__] end ‹$VERBOSE› is set to ‹true› during the execution of the block, so you don’t need to do so yourself. If you have other code that depends on the value of $VERBOSE, that can be done with ‹#with_verbose› expect nil do with_verbose nil do $VERBOSE end end § Errors You should always be expecting errors from – and in, but that’s a different story – your code: expect ArgumentError do Integer('1 + 1') end Often, not only the type of the error, but its description, is important to check: expect StandardError.new('message') do raise StandardError.new('message') end As with ‹Strings›, ‹Regexps› can be used to check the error description: expect StandardError.new(/mess/) do raise StandardError.new('message') end § Queries Through Symbols Symbols are generally matched against symbols, but as a special case, symbols ending with ‹?› are seen as expectations on the result of query methods on the result of the block, given that the method is of zero arity and that the result isn’t a Symbol itself. Simply expect a symbol ending with ‹?›: expect :empty? do [] end To expect it’s negation, expect the same symbol beginning with ‹not_›: expect :not_nil? do [1, 2, 3] end This is the same as expect true do [].empty? end and expect false do [1, 2, 3].empty? end but provides much clearer failure messages. It also makes the expectation’s intent a lot clearer. § Queries By Proxy There’s also a way to make the expectations of query methods explicit by invoking methods on the result of the block. For example, to check that the even elements of the Array ‹[1, 2, 3]› include ‹1› you could write expect result.to.include? 1 do [1, 2, 3].reject{ |e| e.even? } end You could likewise check that the result doesn’t include 2: expect result.not.to.include? 2 do [1, 2, 3].reject{ |e| e.even? } end This is the same as (and executes a little bit slower than) writing expect false do [1, 2, 3].reject{ |e| e.even? }.include? 2 end but provides much clearer failure messages. Given that these two last examples would fail, you’d get a message saying “[1, 2, 3]#include?(2)” instead of the terser “true≠false”. It also clearly separates the actual expectation from the set-up. The keyword for this kind of expectations is ‹result›. This may be followed by any of the methods • ‹#not› • ‹#to› • ‹#be› • ‹#have› or any other method you will want to call on the result. The methods ‹#to›, ‹#be›, and ‹#have› do nothing except improve readability. The ‹#not› method inverts the expectation. § Literal Literals If you need to literally check against any of the types of objects otherwise treated specially, that is, any instances of • ‹Module› • ‹Range› • ‹Regexp› • ‹Exception› • ‹Symbol›, given that it ends with ‹?› you can do so by wrapping it in ‹literal(…)›: expect literal(:empty?) do :empty? end You almost never need to do this, as, for all but symbols, instances will match accordingly as well. § Expectations on Behavior We expect our objects to be on their best behavior. Lookout allows you to make sure that they are. Reception expectations let us verify that a method is called in the way that we expect it to be: expect mock.to.receive.to_str(without_arguments){ '123' } do |o| o.to_str end Here, ‹#mock› creates a mock object, an object that doesn’t respond to anything unless you tell it to. We tell it to expect to receive a call to ‹#to_str› without arguments and have ‹#to_str› return ‹'123'› when called. The mock object is then passed in to the block so that the expectations placed upon it can be fulfilled. Sometimes we only want to make sure that a method is called in the way that we expect it to be, but we don’t care if any other methods are called on the object. A stub object, created with ‹#stub›, expects any method and returns a stub object that, again, expects any method, and thus fits the bill. expect stub.to.receive.to_str(without_arguments){ '123' } do |o| o.to_str if o.convertable? end You don’t have to use a mock object to verify that a method is called: expect Object.to.receive.name do Object.name end As you have figured out by now, the expected method call is set up by calling ‹#receive› after ‹#to›. ‹#Receive› is followed by a call to the method to expect with any expected arguments. The body of the expected method can be given as the block to the method. Finally, an expected invocation count may follow the method. Let’s look at this formal specification in more detail. The expected method arguments may be given in a variety of ways. Let’s introduce them by giving some examples: expect mock.to.receive.a do |m| m.a end Here, the method ‹#a› must be called with any number of arguments. It may be called any number of times, but it must be called at least once. If a method must receive exactly one argument, you can use ‹Object›, as the same matching rules apply for arguments as they do for state expectations: expect mock.to.receive.a(Object) do |m| m.a 0 end If a method must receive a specific argument, you can use that argument: expect mock.to.receive.a(1..2) do |m| m.a 1 end Again, the same matching rules apply for arguments as they do for state expectations, so the previous example expects a call to ‹#a› with 1, 2, or the Range 1..2 as an argument on ‹m›. If a method must be invoked without any arguments you can use ‹without_arguments›: expect mock.to.receive.a(without_arguments) do |m| m.a end You can of course use both ‹Object› and actual arguments: expect mock.to.receive.a(Object, 2, Object) do |m| m.a nil, 2, '3' end The body of the expected method may be given as the block. Here, calling ‹#a› on ‹m› will give the result ‹1›: expect mock.to.receive.a{ 1 } do |m| raise 'not 1' unless m.a == 1 end If no body has been given, the result will be a stub object. To take a block, grab a block parameter and ‹#call› it: expect mock.to.receive.a{ |&b| b.call(1) } do |m| j = 0 m.a{ |i| j = i } raise 'not 1' unless j == 1 end To simulate an ‹#each›-like method, ‹#call› the block several times. Invocation count expectations can be set if the default expectation of “at least once” isn’t good enough. The following expectations are possible • ‹#at_most_once› • ‹#once› • ‹#at_least_once› • ‹#twice› And, for a given ‹N›, • ‹#at_most(N)› • ‹#exactly(N)› • ‹#at_least(N)› § Utilities: Stubs Method stubs are another useful thing to have in a unit testing framework. Sometimes you need to override a method that does something a test shouldn’t do, like access and alter bank accounts. We can override – stub out – a method by using the ‹#stub› method. Let’s assume that we have an ‹Account› class that has two methods, ‹#slips› and ‹#total›. ‹#Slips› retrieves the bank slips that keep track of your deposits to the ‹Account› from a database. ‹#Total› sums the ‹#slips›. In the following test we want to make sure that ‹#total› does what it should do without accessing the database. We therefore stub out ‹#slips› and make it return something that we can easily control. expect 6 do |m| stub(Class.new{ def slips raise 'database not available' end def total slips.reduce(0){ |m, n| m.to_i + n.to_i } end }.new, :slips => [1, 2, 3]){ |account| account.total } end To make it easy to create objects with a set of stubbed methods there’s also a convenience method: expect 3 do s = stub(:a => 1, :b => 2) s.a + s.b end This short-hand notation can also be used for the expected value: expect stub(:a => 1, :b => 2).to.receive.a do |o| o.a + o.b end and also works for mock objects: expect mock(:a => 2, :b => 2).to.receive.a do |o| o.a + o.b end Blocks are also allowed when defining stub methods: expect 3 do s = stub(:a => proc{ |a, b| a + b }) s.a(1, 2) end If need be, we can stub out a specific method on an object: expect 'def' do stub('abc', :to_str => 'def'){ |a| a.to_str } end The stub is active during the execution of the block. § Overriding Constants Sometimes you need to override the value of a constant during the execution of some code. Use ‹#with_const› to do just that: expect 'hello' do with_const 'A::B::C', 'hello' do A::B::C end end Here, the constant ‹A::B::C› is set to ‹'hello'› during the execution of the block. None of the constants ‹A›, ‹B›, and ‹C› need to exist for this to work. If a constant doesn’t exist it’s created and set to a new, empty, ‹Module›. The value of ‹A::B::C›, if any, is restored after the block returns and any constants that didn’t previously exist are removed. § Overriding Environment Variables Another thing you often need to control in your tests is the value of environment variables. Depending on such global values is, of course, not a good practice, but is often unavoidable when working with external libraries. ‹#With_env› allows you to override the value of environment variables during the execution of a block by giving it a ‹Hash› of key/value pairs where the key is the name of the environment variable and the value is the value that it should have during the execution of that block: expect 'hello' do with_env 'INTRO' => 'hello' do ENV['INTRO'] end end Any overridden values are restored and any keys that weren’t previously a part of the environment are removed when the block returns. § Overriding Globals You may also want to override the value of a global temporarily: expect 'hello' do with_global :$stdout, StringIO.new do print 'hello' $stdout.string end end You thus provide the name of the global and a value that it should take during the execution of a block of code. The block gets passed the overridden value, should you need it: expect true do with_global :$stdout, StringIO.new do |overridden| $stdout != overridden end end § Integration Lookout can be used from Rake¹. Simply install Lookout-Rake²: % gem install lookout-rake and add the following code to your Rakefile require 'lookout-rake-3.0' Lookout::Rake::Tasks::Test.new Make sure to read up on using Lookout-Rake for further benefits and customization. ¹ Read more about Rake at http://rake.rubyforge.org/ ² Get information on Lookout-Rake at http://disu.se/software/lookout-rake/ § API Lookout comes with an API¹ that let’s you create things such as new expected values, difference reports for your types, and so on. ¹ See http://disu.se/software/lookout/api/ § Interface Design The default output of Lookout can Spartanly be described as Spartan. If no errors or failures occur, no output is generated. This is unconventional, as unit testing frameworks tend to dump a lot of information on the user, concerning things such as progress, test count summaries, and flamboyantly colored text telling you that your tests passed. None of this output is needed. Your tests should run fast enough to not require progress reports. The lack of output provides you with the same amount of information as reporting success. Test count summaries are only useful if you’re worried that your tests aren’t being run, but if you worry about that, then providing such output doesn’t really help. Testing your tests requires something beyond reporting some arbitrary count that you would have to verify by hand anyway. When errors or failures do occur, however, the relevant information is output in a format that can easily be parsed by an ‹'errorformat'› for Vim or with {Compilation Mode}¹ for Emacs². Diffs are generated for Strings, Arrays, Hashes, and I/O. ¹ Read up on Compilation mode for Emacs at http://www.emacswiki.org/emacs/CompilationMode ² Visit The GNU Foundation’s Emacs’ software page at http://www.gnu.org/software/emacs/ § External Design Let’s now look at some of the points made in the introduction in greater detail. Lookout only allows you to set one expectation per test. If you’re testing behavior with a reception expectation, then only one method-invocation expectation can be set. If you’re testing state, then only one result can be verified. It may seem like this would cause unnecessary duplication between tests. While this is certainly a possibility, when you actually begin to try to avoid such duplication you find that you often do so by improving your interfaces. This kind of restriction tends to encourage the use of value objects, which are easy to test, and more focused objects, which require simpler tests, as they have less behavior to test, per method. By keeping your interfaces focused you’re also keeping your tests focused. Keeping your tests focused improves, in itself, test isolation, but let’s look at something that hinders it: setup and tear-down methods. Most unit testing frameworks encourage test fragmentation by providing setup and tear-down methods. Setup methods create objects and, perhaps, just their behavior for a set of tests. This means that you have to look in two places to figure out what’s being done in a test. This may work fine for few methods with simple set-ups, but makes things complicated when the number of tests increases and the set-up is complex. Often, each test further adjusts the previously set-up object before performing any verifications, further complicating the process of figuring out what state an object has in a given test. Tear-down methods clean up after tests, perhaps by removing records from a database or deleting files from the file-system. The duplication that setup methods and tear-down methods hope to remove is better avoided by improving your interfaces. This can be done by providing better set-up methods for your objects and using idioms such as {Resource Acquisition Is Initialization}¹ for guaranteed clean-up, test or no test. By not using setup and tear-down methods we keep everything pertinent to a test in the test itself, thus improving test isolation. (You also won’t {slow down your tests}² by keeping unnecessary state.) Most unit test frameworks also allow you to create arbitrary test helper methods. Lookout doesn’t. The same rationale as that that has been crystallized in the preceding paragraphs applies. If you need helpers you’re interface isn’t good enough. It really is as simple as that. To clarify: there’s nothing inherently wrong with test helper methods, but they should be general enough that they reside in their own library. The support for mocks in Lookout is provided through a set of test helper methods that make it easier to create mocks than it would have been without them. Lookout-rack³ is another example of a library providing test helper methods (well, one method, actually) that are very useful in testing web applications that use Rack⁴. A final point at which some unit test frameworks try to fragment tests further is documentation. These frameworks provide ways of describing the whats and hows of what’s being tested, the rationale being that this will provide documentation of both the test and the code being tested. Describing how a stack data structure is meant to work is a common example. A stack is, however, a rather simple data structure, so such a description provides little, if any, additional information that can’t be extracted from the implementation and its tests themselves. The implementation and its tests is, in fact, its own best documentation. Taking the points made in the previous paragraphs into account, we should already have simple, self-describing, interfaces that have easily understood tests associated with them. Rationales for the use of a given data structure or system-design design documentation is better suited in separate documentation focused at describing exactly those issues. ¹ Read the Wikipedia entry for Resource Acquisition Is Initialization at http://en.wikipedia.org/wiki/Resource_Acquisition_Is_Initialization ² Read how 37signals had problems with slow Test::Unit tests at http://37signals.com/svn/posts/2742-the-road-to-faster-tests/ ³ Visit the Lookout-rack home page at http://disu.se/software/lookout-rack/ ⁴ Visit the Rack Rubyforge project page at http://rack.rubyforge.org/ § Internal Design The internal design of Lookout has had a couple of goals. • As few external dependencies as possible • As few internal dependencies as possible • Internal extensibility provides external extensibility • As fast load times as possible • As high a ratio of value objects to mutable objects as possible • Each object must have a simple, obvious name • Use mix-ins, not inheritance for shared behavior • As few responsibilities per object as possible • Optimizing for speed can only be done when you have all the facts § External Dependencies Lookout used to depend on Mocha for mocks and stubs. While benchmarking I noticed that a method in Mocha was taking up more than 300 percent of the runtime. It turned out that Mocha’s method for cleaning up back-traces generated when a mock failed was doing something incredibly stupid: backtrace.reject{ |l| Regexp.new(@lib).match(File.expand_path(l)) } Here ‹@lib› is a ‹String› containing the path to the lib sub-directory in the Mocha installation directory. I reported it, provided a patch five days later, then waited. Nothing happened. {254 days later}¹, according to {Wolfram Alpha}², half of my patch was, apparently – I say “apparently”, as I received no notification – applied. By that time I had replaced the whole mocking-and-stubbing subsystem and dropped the dependency. Many Ruby developers claim that Ruby and its gems are too fast-moving for normal package-managing systems to keep up. This is testament to the fact that this isn’t the case and that the real problem is instead related to sloppy practices. Please note that I don’t want to single out the Mocha library nor its developers. I only want to provide an example where relying on external dependencies can be “considered harmful”. ¹ See the Wolfram Alpha calculation at http://www.wolframalpha.com/input/?i=days+between+march+17%2C+2010+and+november+26%2C+2010 ² Check out the Wolfram Alpha computational knowledge engine at http://www.wolframalpha.com/ § Internal Dependencies Lookout has been designed so as to keep each subsystem independent of any other. The diff subsystem is, for example, completely decoupled from any other part of the system as a whole and could be moved into its own library at a time where that would be of interest to anyone. What’s perhaps more interesting is that the diff subsystem is itself very modular. The data passes through a set of filters that depends on what kind of diff has been requested, each filter yielding modified data as it receives it. If you want to read some rather functional Ruby I can highly recommend looking at the code in the ‹lib/lookout/diff› directory. This lookout on the design of the library also makes it easy to extend Lookout. Lookout-rack was, for example, written in about four hours and about 5 of those 240 minutes were spent on setting up the interface between the two. § Optimizing For Speed The following paragraph is perhaps a bit personal, but might be interesting nonetheless. I’ve always worried about speed. The original Expectations library used ‹extend› a lot to add new behavior to objects. Expectations, for example, used to hold the result of their execution (what we now term “evaluation”) by being extended by a module representing success, failure, or error. For the longest time I used this same method, worrying about the increased performance cost that creating new objects for results would incur. I finally came to a point where I felt that the code was so simple and clean that rewriting this part of the code for a benchmark wouldn’t take more than perhaps ten minutes. Well, ten minutes later I had my results and they confirmed that creating new objects wasn’t harming performance. I was very pleased. § Naming I hate low lines (underscores). I try to avoid them in method names and I always avoid them in file names. Since the current “best practice” in the Ruby community is to put ‹BeginEndStorage› in a file called ‹begin_end_storage.rb›, I only name constants using a single noun. This has had the added benefit that classes seem to have acquired less behavior, as using a single noun doesn’t allow you to tack on additional behavior without questioning if it’s really appropriate to do so, given the rather limited range of interpretation for that noun. It also seems to encourage the creation of value objects, as something named ‹Range› feels a lot more like a value than ‹BeginEndStorage›. (To reach object-oriented-programming Nirvana you must achieve complete value.) § News § 3.0.0 The ‹xml› expectation has been dropped. It wasn’t documented, didn’t suit very many use cases, and can be better implemented by an external library. The ‹arg› argument matcher for mock method arguments has been removed, as it didn’t provide any benefit over using Object. The ‹#yield› and ‹#each› methods on stub and mock methods have been removed. They were slightly weird and their use case can be implemented using block parameters instead. The ‹stub› method inside ‹expect› blocks now stubs out the methods during the execution of a provided block instead of during the execution of the whole except block. When a mock method is called too many times, this is reported immediately, with a full backtrace. This makes it easier to pin down what’s wrong with the code. Query expectations were added. Explicit query expectations were added. Fluent boolean expectations, for example, ‹expect nil.to.be.nil?› have been replaced by query expectations (‹expect :nil? do nil end›) and explicit query expectations (‹expect result.to.be.nil? do nil end›). This was done to discourage creating objects as the expected value and creating objects that change during the course of the test. The ‹literal› expectation was added. Equality (‹#==›) is now checked before “caseity” (‹#===›) for modules, ranges, and regular expressions to match the documentation. § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=now%40disu%2ese&item_name=Lookout § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/lookout/issues § Contributors Contributors to the original expectations codebase are mentioned there. We hope no one on that list feels left out of this list. Please {let us know}¹ if you do. • Nikolai Weibull ¹ Add an issue to the Lookout issue tracker at https://github.com/now/lookout/issues § Licensing Lookout is free software: you may redistribute it and/or modify it under the terms of the {GNU Lesser General Public License, version 3}¹ or later², as published by the {Free Software Foundation}³. ¹ See http://disu.se/licenses/lgpl-3.0/ ² See http://gnu.org/licenses/ ³ See http://fsf.org/

Lookout-Rack Lookout-Rack provides easy interaction with Rack¹ from Lookout². It provides you with a session connected to your Rack application through which you can make requests, check responses, follow redirects and set, inspect, and clear cookies. ¹ See http://rack.rubyforge.org/ ² See http://disu.se/software/lookout/ § Installation Install Lookout-Rack with % gem install lookout-rack § Usage Include the following code in your ‹Rakefile› (provided that you’re using Lookout-Rake¹): require 'lookout-rack-3.0' Lookout::Rake::Tasks::Test.new do |t| t.requires << 'lookout-rack-3.0' end ¹ See http://disu.se/software/lookout-rake/ Then set up a ‹fixtures/config.ru› file that Lookout-Rack will use for loading your Rack app. load 'path/to/app.rb' use Rack::Lint run Path::To::App This file, if it exists, will be loaded during the first call to #session. If it doesn’t exist, ‹config.ru› will be used instead. You can now test your app: Expectations do expect 200 do session.get('/').response.status end end The #session method returns an object that lets you #get, #post, #put, and #delete resources from the Rack app. You call these method with a URI¹ that you want to access/modify together with any parameters that you want to pass and any Rack environment that you want to use (which isn’t very common). For example, let’s get ‹/pizzas/› with olives on them: expect 200 do session.get('/pizzas/', 'olives' => '1').response.status end ¹ Abbreviation for Uniform Resource Identifier The #response method on #session returns a mock Rack response object that can be queried for results. Similarly, there’s a #request method that lets you inspect the request that was made. Lookout-Rack also deals with cookies. Assuming that ‹/cookies/set/› will set any cookies that we pass it and that ‹/cookies/show/› will simply do nothing relevant, the following expectation will pass: expect 'value' => '1' do session. get('/cookies/set/', 'value' => '1'). get('/cookies/show/').request.cookies end Sometimes you may want to set cookies yourself before making a request. You then use the #cookie method, which takes a String of ‹KEY=VALUE› pairs separated by newlines, commas, and/or semicolons and sets those cookies in the session: expect 'value' => '1', 'other' => '2' do session. cookie("value=1\n\nother=2"). get('/cookies/show/').request.cookies end You may also want to clear all cookies in your session using #clear: expect({}) do session. get('/cookies/set', 'value' => '1'). clear. get('/cookies/show').request.cookies end Finally, to test redirects, call the #redirect! method on the session object, assuming that ‹/redirected/› redirects to another location: expect result.redirect? do session.get('/redirected/').response end expect result.not.redirect? do session.get('/redirected/').redirect!.response end That’s basically all there’s to it. You can check the {API documentation}¹ for more information. ¹ See http://disu.se/software/lookout-rack/api/Lookout/Rack/ § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=now@disu.se&item_name=Lookout-Rack § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/lookout-rack/issues § Authors Nikolai Weibull wrote the code, the tests, the documentation, and this README. § Licensing Lookout-Rack is free software: you may redistribute it and/or modify it under the terms of the {GNU Lesser General Public License, version 3}¹ or later², as published by the {Free Software Foundation}³. ¹ See http://disu.se/licenses/lgpl-3.0/ ² See http://gnu.org/licenses/ ³ See http://fsf.org/

Lookout-Rake Lookout-Rake provides Rake¹ tasks for testing using Lookout. ¹ See http://rake.rubyforge.org/ § Installation Install Lookout-Rake with % gem install lookout-rake § Usage Include the following code in your ‹Rakefile›: require 'lookout-rake-3.0' Lookout::Rake::Tasks::Test.new If the ‹:default› task hasn’t been defined it’ll be set to depend on the ‹:test› task. The ‹:check› task will also depend on the ‹:test› task. There’s also a ‹:test:coverage› task that gets defined that uses the coverage library that comes with Ruby 1.9 to check the test coverage when the tests are run. You can hook up your test task to use your Inventory¹: load File.expand_path('../lib/library-X.0/version.rb', __FILE__) Lookout::Rake::Tasks::Test.new :inventory => Library::Version Also, if you use the tasks that come with Inventory-Rake², the test task will hook into the inventory you tell them to use automatically, that is, the following will do: load File.expand_path('../lib/library-X.0/version.rb', __FILE__) Inventory::Rake::Tasks.define Library::Version Lookout::Rake::Tasks::Test.new For further usage information, see the {API documentation}³. ¹ Inventory: http://disu.se/software/inventory/ ² Inventory-Rake: http://disu.se/software/inventory-rake/ ³ API: http://disu.se/software/lookout-rake/api/Lookout/Rake/Tasks/Test/ § Integration To use Lookout together with Vim¹, place ‹contrib/rakelookout.vim› in ‹~/.vim/compiler› and add compiler rakelookout to ‹~/.vim/after/ftplugin/ruby.vim›. Executing ‹:make› from inside Vim will now run your tests and an errors and failures can be visited with ‹:cnext›. Execute ‹:help quickfix› for additional information. Another useful addition to your ‹~/.vim/after/ftplugin/ruby.vim› file may be nnoremap <buffer> <silent> <Leader>M <Esc>:call <SID>run_test()<CR> let b:undo_ftplugin .= ' | nunmap <buffer> <Leader>M' function! s:run_test() let test = expand('%') let line = 'LINE=' . line('.') if test =~ '^lib/' let test = substitute(test, '^lib/', 'test/', '') let line = "" endif execute 'make' 'TEST=' . shellescape(test) line endfunction Now, pressing ‹<Leader>M› will either run all tests for a given class, if the implementation file is active, or run the test at or just before the cursor, if the test file is active. This is useful if you’re currently receiving a lot of errors and/or failures and want to focus on those associated with a specific class or on a specific test. ¹ Find out more about Vim at http://www.vim.org/ § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=now%40disu%2ese&item_name=Nikolai%20Weibull%20Software%20Services § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/lookout-rake/issues § Authors Nikolai Weibull wrote the code, the tests, the manual pages, and this README.

U U extends Ruby’s Unicode support. It provides a string class called U::String with an interface that mimics that of the String class in Ruby 2.0, but that can also be used from both Ruby 1.8. This interface also has more complete Unicode support and never modifies the receiver. Thus, a U::String is an immutable value object. U comes with complete and very accurate documentation¹. The documentation can realistically also be used as a reference to the Ruby String API and may actually be preferable, as it’s a lot more explicit and complete than the documentation that comes with Ruby. ¹ See http://disu.se/software/u-1.0/api/ § Installation Install u with % gem install u § Usage Usage is basically the following: require 'u-1.0' a = 'äbc' a.upcase # ⇒ 'äBC' a.u.upcase # ⇒ 'ÄBC' That is, you require the library, then you invoke #u on a String. This’ll give you a U::String that has much better Unicode support than a normal String. It’s important to note that U only uses UTF-8, which means that #u will try to #encode the String as such. This shouldn’t be an issue in most cases, as UTF-8 is now more or less the universal encoding – and rightfully so. As U::Strings¹ are immutable value objects, there’s also a U::Buffer² available for building U::Strings efficiently. See the API³ for more complete usage information. The following sections will only cover the extensions and differences that U::String exhibit from Ruby’s built-in String class. ¹ See http://disu.se/software/u-1.0/api/U/String/ ² See http://disu.se/software/u-1.0/api/U/Buffer/ ³ See http://disu.se/software/u-1.0/api/ § Unicode Properties There are quite a few property-checking interrogators that let you check if all characters in a U::String have the given Unicode property: • #alnum?¹ • #alpha?² • #assigned?³ • #case_ignorable?⁴ • #cased?⁵ • #cntrl?⁶ • #defined?⁷ • #digit?⁸ • #graph?⁹ • #newline?¹⁰ • #print?¹¹ • #punct?¹² • #soft_dotted?¹³ • #space?¹⁴ • #title?¹⁵ • #valid?¹⁶ • #wide?¹⁷ • #wide_cjk?¹⁸ • #xdigit?¹⁹ • #zero_width?²⁰ ¹ See http://disu.se/software/u-1.0/api/U/String/#alnum-p-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#alpha-p-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#assigned-p-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#case_ignorable-p-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#cased-p-instance-method ⁶ See http://disu.se/software/u-1.0/api/U/String/#cntrl-p-instance-method ⁷ See http://disu.se/software/u-1.0/api/U/String/#defined-p-instance-method ⁸ See http://disu.se/software/u-1.0/api/U/String/#digit-p-instance-method ⁹ See http://disu.se/software/u-1.0/api/U/String/#graph-p-instance-method ¹⁰ See http://disu.se/software/u-1.0/api/U/String/#newline-p-instance-method ¹¹ See http://disu.se/software/u-1.0/api/U/String/#print-p-instance-method ¹² See http://disu.se/software/u-1.0/api/U/String/#punct-p-instance-method ¹³ See http://disu.se/software/u-1.0/api/U/String/#soft_dotted-p-instance-method ¹⁴ See http://disu.se/software/u-1.0/api/U/String/#space-p-instance-method ¹⁵ See http://disu.se/software/u-1.0/api/U/String/#title-p-instance-method ¹⁶ See http://disu.se/software/u-1.0/api/U/String/#valid-p-instance-method ¹⁷ See http://disu.se/software/u-1.0/api/U/String/#wide-p-instance-method ¹⁸ See http://disu.se/software/u-1.0/api/U/String/#wide_cjk-p-instance-method ¹⁹ See http://disu.se/software/u-1.0/api/U/String/#xdigit-p-instance-method ²⁰ See http://disu.se/software/u-1.0/api/U/String/#zero_width-p-instance-method Similar to these methods are • #folded?¹ • #lower?² • #upper?³ which check whether a ‹U::String› has been cased in a given manner. ¹ See http://disu.se/software/u-1.0/api/U/String/#folded-p-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#lower-p-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#upper-p-instance-method There’s also a #normalized?¹ method that checks whether a ‹U::String› has been normalized on a given form. ¹ See http://disu.se/software/u-1.0/api/U/String/#normalized-p-instance-method You can also access certain Unicode properties of the characters of a U::String: • #canonical_combining_class¹ • #general_category² • #grapheme_break³ • #line_break⁴ • #script⁵ • #word_break⁶ ¹ See http://disu.se/software/u-1.0/api/U/String/#canonical_combining_class-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#general_category-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#grapheme_break-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#line_break-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#script-instance-method ⁶ See http://disu.se/software/u-1.0/api/U/String/#word_break-instance-method § Locale-specific Comparisons Comparisons of U::Strings respect the current locale (and also allow you to specify a locale to use): ‹#&lt;=&gt;›¹, #casecmp², and #collation_key³. ¹ See http://disu.se/software/u-1.0/api/U/String/#comparison-operator ² See http://disu.se/software/u-1.0/api/U/String/#casecmp-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#collation_key-instance-method § Additional Enumerators There are a couple of additional enumerators in #each_grapheme_cluster¹ and #each_word² (along with aliases #grapheme_clusters³ and #words⁴). ¹ See http://disu.se/software/u-1.0/api/U/String/#each_grapheme_cluster-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#each_word-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#grapheme_clusters-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#words-instance-method § Unicode-aware Sub-sequence Removal #Chomp¹, #chop², #lstrip³, #rstrip⁴, and #strip⁵ all look for Unicode newline and space characters, rather than only ASCII ones. ¹ See http://disu.se/software/u-1.0/api/U/String/#chomp-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#chop-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#lstrip-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#rstrip-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#strip-instance-method § Unicode-aware Conversions Case-shifting methods #downcase¹ and #upcase² do proper Unicode casing and the interface is further augmented by #foldcase³ and #titlecase⁴. #Mirror⁵ and #normalize⁶ do conversions similar in nature to the case-shifting methods. ¹ See http://disu.se/software/u-1.0/api/U/String/#downcase-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#upcase-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#foldcase-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#titlecase-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#mirror-instance-method ⁶ See http://disu.se/software/u-1.0/api/U/String/#normalize-instance-method § Width Calculations #Width¹ will return the number of cells on a terminal that a U::String will occupy. #Center², #ljust³, and #rjust⁴ deal in width rather than length, making them much more useful for generating terminal output. #%⁵ (and its alias #format⁶) similarly deal in width. ¹ See http://disu.se/software/u-1.0/api/U/String/#width-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#center-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#ljust-instance-method ⁴ See http://disu.se/software/u-1.0/api/U/String/#rjust-instance-method ⁵ See http://disu.se/software/u-1.0/api/U/String/#modulo-operator ⁶ See http://disu.se/software/u-1.0/api/U/String/#format-instance-method § Extended Type Conversions Finally, #hex¹, #oct², and #to_i³ use Unicode alpha-numerics for their respective conversions. ¹ See http://disu.se/software/u-1.0/api/U/String/#hex-instance-method ² See http://disu.se/software/u-1.0/api/U/String/#oct-instance-method ³ See http://disu.se/software/u-1.0/api/U/String/#to_i-instance-method § News § 1.0.0 Initial public release! § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&amp;business=now@disu.se&amp;item_name=U § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/u/issues § Authors Nikolai Weibull wrote the code, the tests, the documentation, and this README. § Licensing U is free software: you may redistribute it and/or modify it under the terms of the {GNU Lesser General Public License, version 3}¹ or later², as published by the {Free Software Foundation}³. ¹ See http://disu.se/licenses/lgpl-3.0/ ² See http://gnu.org/licenses/ ³ See http://fsf.org/

Value Value is a library for defining immutable value objects in Ruby. A value object is an object whose equality to other objects is determined by its value, not its identity, think dates and amounts of money. A value object should also be immutable, as you don’t want the date “2013-04-22” itself to change but the current date to change from “2013-04-22” to “2013-04-23”. That is, you don’t want entries in a calendar for 2013-04-22 to move to 2013-04-23 simply because the current date changes from 2013-04-22 to 2013-04-23. A value object consists of one or more attributes stored in instance variables. Value sets up an #initialize method for you that let’s you set these attributes, as, value objects being immutable, this’ll be your only chance to do so. Value also adds equality checks ‹#==› and ‹#eql?› (which are themselves equivalent), a ‹#hash› method, a nice ‹#inspect› method, and a protected attribute reader for each attribute. You may of course add any additional methods that your value object will benefit from. That’s basically all there’s too it. Let’s now look at using the Value library. § Usage You create value object class by invoking ‹#Value› inside the class (module) you wish to make into a value object class. Let’s create a class that represent points on a plane: class Point Value :x, :y end A ‹Point› is thus a value object consisting of two sub-values ‹x› and ‹y› (the coordinates). Just from invoking ‹#Value›, a ‹Point› object will have a constructor that takes two arguments to set instance variables ‹@x› and ‹@y›, equality checks ‹#==› and ‹#eql?› (which are the same), a ‹#hash› method, a nice ‹#inspect› method, and two protected attribute readers ‹#x› and ‹#y›. We can thus already creat ‹Point›s: origo = Point.new(0, 0) The default of making the attribute readers protected is often good practice, but for a ‹Point› it probably makes sense to be able to access its coordinates: class Point public(*attributes) end This’ll make all attributes of ‹Point› public. You can of course choose to only make certain attributes public: class Point public :x end Note that this public is standard Ruby functionality. Adding a method to ‹Point› is of course also possible and very much Rubyish: class Point def distance(other) Math.sqrt((other.x - x)**2 + (other.y - y)**2) end end For some value object classes you might want to support optional attributes. This is done by providing a default value for the attribute, like so: class Money Value :amount, [:currency, :USD] end Here, the ‹currency› attribute will default to ‹:USD›. You can create ‹Money› via dollars = Money.new(2) but also kronor = Money.new(2, :SEK) All required attributes must come before any optional attributes. Splat attributes are also supported: class List Value :'*elements' end empty = List.new suits = List.new(:spades, :hearts, :diamonds, :clubs) Splat attributes are optional. Finally, block attributes are also available: class Block Value :'&block' end block = Block.new{ |e| e * 2 } Block attributes are optional. Comparison beyond ‹#==› is possible by specifingy the ‹:comparable› option to ‹#Value›, listing one or more attributes that should be included in the comparison: class Vector Value :a, :b, :comparable => :a end Note that equality (‹#==› and ‹#eql?›) is always defined based on all attributes, regardless of arguments to ‹:comparable›. Here we say that comparisons between ‹Vector›s should be made between the values of the ‹a› attribute only. We can also make comparisons between all attributes of a value object: class Vector Value :a, :b, :comparable => true end To sum things up, let’s use all possible arguments to ‹#Value› at once: class Method Value :file, :line, [:name, 'unnamed'], :'*args', :'&block', :comparable => [:file, :line] end A ‹Method› consists of file and line information, a possible name, some arguments, possibly a block, and is comparable on the file and line on which they appear. Check out the {full API documentation}¹ for a more explicit description, should you need it or should you want to extend it. ¹ See http://disu.se/software/value/api/ § Financing Currently, most of my time is spent at my day job and in my rather busy private life. Please motivate me to spend time on this piece of software by donating some of your money to this project. Yeah, I realize that requesting money to develop software is a bit, well, capitalistic of me. But please realize that I live in a capitalistic society and I need money to have other people give me the things that I need to continue living under the rules of said society. So, if you feel that this piece of software has helped you out enough to warrant a reward, please PayPal a donation to now@disu.se¹. Thanks! Your support won’t go unnoticed! ¹ Send a donation: https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=now%40disu%2ese&item_name=Value § Reporting Bugs Please report any bugs that you encounter to the {issue tracker}¹. ¹ See https://github.com/now/value/issues § Authors Nikolai Weibull wrote the code, the tests, the manual pages, and this README. § Licensing Value is free software: you may redistribute it and/or modify it under the terms of the {GNU Lesser General Public License, version 3}¹ or later², as published by the {Free Software Foundation}³. ¹ See http://disu.se/licenses/lgpl-3.0/ ² See http://gnu.org/licenses/ ³ See http://fsf.org/