Refactor slash command definition

3 files changed, 97 insertions, 72 deletions

diff --git a/lib/gitlab/slash_commands/command_definition.rb b/lib/gitlab/slash_commands/command_definition.rb
new file mode 100644
index 00000000000..5dec6c91869
--- /dev/null
+++ b/lib/gitlab/slash_commands/command_definition.rb
@@ -0,0 +1,57 @@
+module Gitlab
+  module SlashCommands
+    class CommandDefinition
+      attr_accessor :name, :aliases, :description, :params, :condition_block, :action_block
+
+      def valid?
+        name.present?
+      end
+
+      def all_names
+        [name, *aliases]
+      end
+
+      def noop?
+        action_block.nil?
+      end
+
+      def available?(opts)
+        return true unless condition_block
+
+        context = OpenStruct.new(opts)
+        context.instance_exec(&condition_block)
+      end
+
+      def to_description(opts)
+        return description unless description.respond_to?(:call)
+
+        context = OpenStruct.new(opts)
+        context.instance_exec(&description) rescue ''
+      end
+
+      def execute(context, opts, *args)
+        return if noop? || !available?(opts)
+
+        block_arity = action_block.arity
+        return unless block_arity == -1 || block_arity == args.size
+
+        context.instance_exec(*args, &action_block)
+      end
+
+      def to_h(opts)
+        desc = description
+        if desc.respond_to?(:call)
+          context = OpenStruct.new(opts)
+          desc = context.instance_exec(&desc) rescue ''
+        end
+
+        {
+          name: name,
+          aliases: aliases,
+          description: desc,
+          params: params
+        }
+      end
+    end
+  end
+end
diff --git a/lib/gitlab/slash_commands/dsl.rb b/lib/gitlab/slash_commands/dsl.rb
index ce659aff1da..58ba7027f84 100644
--- a/lib/gitlab/slash_commands/dsl.rb
+++ b/lib/gitlab/slash_commands/dsl.rb
@@ -4,64 +4,16 @@ module Gitlab
       extend ActiveSupport::Concern
 
       included do
-        cattr_accessor :definitions
-      end
-
-      def execute_command(name, *args)
-        name = name.to_sym
-        cmd_def = self.class.definitions.find do |cmd_def|
-          self.class.command_name_and_aliases(cmd_def).include?(name)
+        cattr_accessor :command_definitions, instance_accessor: false do
+          []
         end
-        return unless cmd_def && cmd_def[:action_block]
-        return if self.class.command_unavailable?(cmd_def, self)
 
-        block_arity = cmd_def[:action_block].arity
-        if block_arity == -1 || block_arity == args.size
-          instance_exec(*args, &cmd_def[:action_block])
+        cattr_accessor :command_definitions_by_name, instance_accessor: false do
+          {}
         end
       end
 
       class_methods do
-        # This method is used to generate the autocompletion menu.
-        # It returns no-op slash commands (such as `/cc`).
-        def command_definitions(opts = {})
-          self.definitions.map do |cmd_def|
-            context = OpenStruct.new(opts)
-            next if command_unavailable?(cmd_def, context)
-
-            cmd_def = cmd_def.dup
-
-            if cmd_def[:description].respond_to?(:call)
-              cmd_def[:description] = context.instance_exec(&cmd_def[:description]) rescue ''
-            end
-
-            cmd_def
-          end.compact
-        end
-
-        # This method is used to generate a list of valid commands in the current
-        # context of `opts`.
-        # It excludes no-op slash commands (such as `/cc`).
-        # This list can then be given to `Gitlab::SlashCommands::Extractor`.
-        def command_names(opts = {})
-          self.definitions.flat_map do |cmd_def|
-            next if cmd_def[:opts].fetch(:noop, false)
-
-            context = OpenStruct.new(opts)
-            next if command_unavailable?(cmd_def, context)
-
-            command_name_and_aliases(cmd_def)
-          end.compact
-        end
-
-        def command_unavailable?(cmd_def, context)
-          cmd_def[:condition_block] && !context.instance_exec(&cmd_def[:condition_block])
-        end
-
-        def command_name_and_aliases(cmd_def)
-          [cmd_def[:name], *cmd_def[:aliases]]
-        end
-
         # Allows to give a description to the next slash command.
         # This description is shown in the autocomplete menu.
         # It accepts a block that will be evaluated with the context given to
@@ -119,19 +71,23 @@ module Gitlab
         #     # Awesome code block
         #   end
         def command(*command_names, &block)
-          opts = command_names.extract_options!
           name, *aliases = command_names
 
-          self.definitions ||= []
-          self.definitions << {
-            name: name,
-            aliases: aliases,
-            description: @description || '',
-            params: @params || [],
-            condition_block: @condition_block,
-            action_block: block,
-            opts: opts
-          }
+          definition = CommandDefinition.new
+          definition.name            =  name
+          definition.aliases         =  aliases
+          definition.description     =  @description || ''
+          definition.params          =  @params || []
+          definition.condition_block =  @condition_block
+          definition.action_block    =  block
+
+          return unless definition.valid?
+
+          self.command_definitions << definition
+
+          definition.all_names.each do |name|
+            self.command_definitions_by_name[name] = definition
+          end
 
           @description = nil
           @params = nil
diff --git a/lib/gitlab/slash_commands/extractor.rb b/lib/gitlab/slash_commands/extractor.rb
index ce0a2eba535..a6838cb5e7c 100644
--- a/lib/gitlab/slash_commands/extractor.rb
+++ b/lib/gitlab/slash_commands/extractor.rb
@@ -7,10 +7,10 @@ module Gitlab
     # extractor = Gitlab::SlashCommands::Extractor.new([:open, :assign, :labels])
     # ```
     class Extractor
-      attr_reader :command_names
+      attr_reader :command_definitions
 
-      def initialize(command_names)
-        @command_names = command_names
+      def initialize(command_definitions)
+        @command_definitions = command_definitions
       end
 
       # Extracts commands from content and return an array of commands.
@@ -26,16 +26,18 @@ module Gitlab
       # ```
       # extractor = Gitlab::SlashCommands::Extractor.new([:open, :assign, :labels])
       # msg = %(hello\n/labels ~foo ~"bar baz"\nworld)
-      # commands = extractor.extract_commands! #=> [['labels', '~foo ~"bar baz"']]
+      # commands = extractor.extract_commands(msg) #=> [['labels', '~foo ~"bar baz"']]
       # msg #=> "hello\nworld"
       # ```
-      def extract_commands!(content)
+      def extract_commands(content, opts)
         return [] unless content
 
+        content = content.dup
+
         commands = []
 
         content.delete!("\r")
-        content.gsub!(commands_regex) do
+        content.gsub!(commands_regex(opts)) do
           if $~[:cmd]
             commands << [$~[:cmd], $~[:args]].reject(&:blank?)
             ''
@@ -44,11 +46,19 @@ module Gitlab
           end
         end
 
-        commands
+        [content.strip, commands]
       end
 
       private
 
+      def command_names(opts)
+        command_definitions.flat_map do |command|
+          next if command.noop?
+
+          command.all_names
+        end.compact
+      end
+
       # Builds a regular expression to match known commands.
       # First match group captures the command name and
       # second match group captures its arguments.
@@ -56,7 +66,9 @@ module Gitlab
       # It looks something like:
       #
       #   /^\/(?<cmd>close|reopen|...)(?:( |$))(?<args>[^\/\n]*)(?:\n|$)/
-      def commands_regex
+      def commands_regex(opts)
+        names = command_names(opts).map(&:to_s)
+
         @commands_regex ||= %r{
             (?<code>
               # Code blocks:
@@ -95,7 +107,7 @@ module Gitlab
               # Command not in a blockquote, blockcode, or HTML tag:
               # /close
 
-              ^\/(?<cmd>#{command_names.join('|')})(?:(\ |$))(?<args>[^\/\n]*)(?:\n|$)
+              ^\/(?<cmd>#{Regexp.union(names)})(?:$|\ (?<args>[^\/\n]*)$)
             )
         }mx
       end