Add commit type (#6)

Add option to specify commit type

.travis.yml

@@ -1,9 +1,11 @@
 language: ruby
 cache: bundler
+sudo: false
 rvm:
   - 1.9.3
   - 2.0.0
   - 2.1.0
   - 2.2.0
+  - 2.3.0
   - ruby-head
 script: 'bundle exec rake'

Gemfile

@@ -1,4 +1,5 @@
-source 'https://rubygems.org'
+# frozen_string_literal: true
+source "https://rubygems.org"
 
 # Specify your gem's dependencies in jekyll_version_plugin.gemspec
 gemspec

README.md

@@ -5,35 +5,44 @@
 
 ### Description
 
-A Liquid tag plugin for [Jekyll](http://jekyllrb.com/) that renders a version identifier for your Jekyll site sourced from the `git` repository containing your code. Great if you want to display the version of your project on your site dynamically each time your site is built.
+A Liquid tag plugin for [Jekyll](http://jekyllrb.com/) that renders a version identifier for your Jekyll site sourced from the `git` repository containing your code. Great if you want to display the version of your project on your site automatically each time your site is built.
 
 Identify and highlight the build of your project by calling the tag from your Jekyll project.
 
+##### This Jekyll view code will generate ...
+
+Given a `git` repo with the latest tag of *3.0.0* and *5* commits since tagged, the commit `ga189420` being the latest.
+
 ```ruby
-# this Jekyll view code will generate ...
 <p>Build: {% project_version %}</p>
 ```
 
+##### This html
+
 ```html
-<!-- this html -->
 <p>Build: 3.0.0-5-ga189420</p>
 ```
 
 
 ### Features
 
-Stand back, hold onto your hats... the **jekyll-version-plugin** has 1x feature.
+The **jekyll-version-plugin** has 1x feature with a few options;
 
 * Render a version of your project via `git`.
+  * Use the `git-describe` command with *long* or *short* option
+  * Use the `git rev-parse` on **HEAD** with *long* or *short* option
+
 
 ### Requirements
 
 * Your project is version controlled in `git`.
 
+
 ### Usage
 
 As mentioned by [Jekyll's documentation](http://jekyllrb.com/docs/plugins/#installing-a-plugin) you have two options; manually import the source file or require the plugin as a `gem`.
 
+
 #### Require gem
 
 Add the `jekyll_version_plugin` to your site `_config.yml` file for Jekyll to import the plugin as a gem.
@@ -42,53 +51,85 @@ Add the `jekyll_version_plugin` to your site `_config.yml` file for Jekyll to im
 gems: ['jekyll_version_plugin']
 ```
 
+
 #### Manual import
 
 Just download the source file into your `_plugins` directory, e.g.
 
 ```bash
 # Create the _plugins dir if needed and download project_version_tag plugin
 $ mkdir -p _plugins && cd _plugins
-$ wget https://raw.githubusercontent.com/rob-murray/jekyll-version-plugin/master/lib/project_version_tag.rb
+$ wget https://raw.githubusercontent.com/rob-murray/jekyll-version-plugin/master/lib/jekyll_version_plugin.rb
 ```
 
+
 #### Plugin tag usage
 
-Wherever you want to display the version, just add the snippet below in your content and the version will be rendered when the Jekyll project is built.
+The plugin can be called anywhere in your template with or without parameters;
+
+```ruby
+{% project_version *params %}
+{% project_version type format %}
+```
+
+* **type** is what to use for versioning, either `tag` or `commit` - default of `tag`
+* **format** is the format of the output, `short` or `long` - defaults to `short`
+
+Wherever you want to display the version, just add one of the snippets below in your content and the version will be rendered when the Jekyll project is built.
+
 
 ```ruby
-{% project_version %}
+# Default options of `tag short`
+{% project_version %} # => will run `git describe --tags --always`
+
+# To render a short tag description like `3.0.0`
+{% project_version tag short %} # => will run `git describe --tags --always`
+
+# To render a more details tag description like `3.0.0-5-ga189420`
+{% project_version tag long %} # => will run `git describe --tags --always --long`
+
+# To render a short commitish like `151ebce`
+{% project_version commit short %} # => will run `git rev-parse --short HEAD`
+
+# To render a longer commitsh like `151ebce149c5886bcf2923db18d73742901eb976`
+{% project_version commit long %} # => will run `git rev-parse HEAD`
 ```
 
 This will simply output the version number, you can then apply your own styling as necessary. Or just `html` comment it out if you don't want it visible.
 
+
 ### Output
 
 Happy path is a `git` repo with releases that are tagged, if this is the case then the output will be something like this;
 
 `3.0.0` or `3.0.0-5-ga189420`
 
-If the repository does not have any `tags` then it will grab the short sha of the last commit, for example;
+If you select the *commit* option then the output will be something like this;
 
 `a189420`
 
+If you have selected the *tags* option and the repository does not have any `tags` then it will grab the short sha of the last commit, see above;
+
 If for any reason this fails then the output will just be a *sorry* message. Sorry about that.
 
 `Sorry, could not read project version at the moment`
 
 
 ### Technical wizardry
 
-The plugin just calls `git describe` - For more information see [git documentation](http://git-scm.com/docs/git-describe).
+The plugin just calls `git describe` or `git rev-parse HEAD` - For more information see [git-describe](http://git-scm.com/docs/git-describe) and [git rev-parse](https://git-scm.com/docs/git-rev-parse).
 
 ```bash
 $ git describe --tags --long
+$ git rev-parse --short HEAD
 ```
 
+
 ### Contributions
 
 Please use the GitHub pull-request mechanism to submit contributions.
 
+
 ### License
 
 This project is available for use under the MIT software license.

Rakefile

@@ -1,8 +1,9 @@
+# frozen_string_literal: true
 require "bundler/gem_tasks"
-require 'rspec/core'
-require 'rspec/core/rake_task'
+require "rspec/core"
+require "rspec/core/rake_task"
 
-task :default => :spec
+task default: :spec
 
 desc "Run all specs in spec directory (excluding plugin specs)"
 RSpec::Core::RakeTask.new(:spec)

jekyll_version_plugin.gemspec

@@ -1,22 +1,24 @@
 # coding: utf-8
-lib = File.expand_path('../lib', __FILE__)
+# frozen_string_literal: true
+lib = File.expand_path("../lib", __FILE__)
 $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 
 Gem::Specification.new do |spec|
-  spec.name          = 'jekyll_version_plugin'
-  spec.version       = '1.0.2'
-  spec.authors       = ['Rob Murray']
-  spec.email         = ['robmurray17@gmail.com']
-  spec.summary       = %q{A Liquid tag plugin for Jekyll that renders a version identifier for your Jekyll site, sourced from the git repository.}
-  spec.homepage      = 'https://github.com/rob-murray/jekyll-version-plugin'
-  spec.license       = 'MIT'
+  spec.name                   = "jekyll_version_plugin"
+  spec.version                = "1.0.2"
+  spec.authors                = ["Rob Murray"]
+  spec.email                  = ["robmurray17@gmail.com"]
+  spec.summary                = "A Liquid tag plugin for Jekyll that renders a version identifier for your Jekyll site, sourced from the git repository."
+  spec.homepage               = "https://github.com/rob-murray/jekyll-version-plugin"
+  spec.license                = "MIT"
+  spec.required_ruby_version  = ">= 1.9.3"
 
   spec.files         = `git ls-files -z`.split("\x0")
   spec.executables   = spec.files.grep(%r{^bin/}) { |f| File.basename(f) }
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
-  spec.require_paths = ['lib']
+  spec.require_paths = ["lib"]
 
-  spec.add_development_dependency 'bundler', '~> 1.6'
-  spec.add_development_dependency 'rake'
-  spec.add_development_dependency 'rspec', '~> 3.0'
+  spec.add_development_dependency "bundler", "~> 1.6"
+  spec.add_development_dependency "rake"
+  spec.add_development_dependency "rspec", "~> 3.5"
 end

lib/jekyll_version_plugin.rb

@@ -1,2 +1,103 @@
-# Want to use a different name for the tag class than the gem name :)
-require 'project_version_tag'
+# frozen_string_literal: true
+module Jekyll
+  module VersionPlugin
+    # A Jekyll Tag type that renders a version identifier for your Jekyll site
+    # sourced from the `git` repository containing your code.
+    #
+    class Tag < Liquid::Tag
+      NO_GIT_MESSAGE          = "Oops, are you sure this is a git project?".freeze
+      UNABLE_TO_PARSE_MESSAGE = "Sorry, could not read the project version at the moment".freeze
+      OPTION_NOT_SPECIFIED    = nil
+
+      attr_writer :system_wrapper # for testing
+
+      # A wrapper around system calls; mock/stub this in testing
+      class SystemWrapper
+        def run(command)
+          `#{command}`
+        end
+
+        def command_succeeded?
+          !$?.nil? && $?.success?
+        end
+
+        def git_repo?
+          system("git rev-parse")
+        end
+      end
+
+      def initialize(_name, params, _tokens)
+        super
+        args    = params.split(/\s+/).map(&:strip)
+        # TODO: When min Ruby version is >=2.0 just use `to_h`
+        @params = Hash[[:type, :format].zip(args)]
+      end
+
+      def render(_context)
+        if git_repo?
+          current_version.chomp
+        else
+          NO_GIT_MESSAGE
+        end
+      end
+
+      private
+
+      attr_reader :params
+
+      # for testing
+      def system_wrapper
+        @system_wrapper ||= SystemWrapper.new
+      end
+
+      def current_version
+        @_current_version ||= begin
+          version = case params.fetch(:type, "tag")
+                    when "tag", OPTION_NOT_SPECIFIED
+                      git_describe || parse_head
+                    when "commit"
+                      parse_head
+                    end
+
+          version || UNABLE_TO_PARSE_MESSAGE
+        end
+      end
+
+      def git_describe
+        tagged_version = case params.fetch(:format, "short")
+                         when "short", OPTION_NOT_SPECIFIED
+                           run("git describe --tags --always")
+                         when "long"
+                           run("git describe --tags --always --long")
+                         end
+
+        tagged_version if command_succeeded?
+      end
+
+      def parse_head
+        head_commitish = case params.fetch(:format, "short")
+                         when "short", OPTION_NOT_SPECIFIED
+                           run("git rev-parse --short HEAD")
+                         when "long"
+                           run("git rev-parse HEAD")
+                         end
+
+        head_commitish if command_succeeded?
+      end
+
+      def run(command)
+        system_wrapper.run(command)
+      end
+
+      def git_repo?
+        system_wrapper.git_repo?
+      end
+
+      def command_succeeded?
+        system_wrapper.command_succeeded?
+      end
+    end
+  end
+end
+
+Liquid::Template.register_tag("project_version", Jekyll::VersionPlugin::Tag)