1 files changed, 77 insertions, 0 deletions
diff --git a/lib/gitlab/git/gitmodules_parser.rb b/lib/gitlab/git/gitmodules_parser.rb
new file mode 100644
index 00000000000..f4e3b5e5129
--- /dev/null
+++ b/lib/gitlab/git/gitmodules_parser.rb
@@ -0,0 +1,77 @@
+module Gitlab
+  module Git
+    class GitmodulesParser
+      def initialize(content)
+        @content = content
+      end
+
+      # Parses the contents of a .gitmodules file and returns a hash of
+      # submodule information, indexed by path.
+      def parse
+        reindex_by_path(get_submodules_by_name)
+      end
+
+      private
+
+      class State
+        def initialize
+          @result = {}
+          @current_submodule = nil
+        end
+
+        def start_section(section)
+          # In some .gitmodules files (e.g. nodegit's), a header
+          # with the same name appears multiple times; we want to
+          # accumulate the configs across these
+          @current_submodule = @result[section] || { 'name' => section }
+          @result[section] = @current_submodule
+        end
+
+        def set_attribute(attr, value)
+          @current_submodule[attr] = value
+        end
+
+        def section_started?
+          !@current_submodule.nil?
+        end
+
+        def submodules_by_name
+          @result
+        end
+      end
+
+      def get_submodules_by_name
+        iterator = State.new
+
+        @content.split("\n").each_with_object(iterator) do |text, iterator|
+          next if text =~ /^\s*#/
+
+          if text =~ /\A\[submodule "(?<name>[^"]+)"\]\z/
+            iterator.start_section($~[:name])
+          else
+            next unless iterator.section_started?
+
+            next unless text =~ /\A\s*(?<key>\w+)\s*=\s*(?<value>.*)\z/
+
+            value = $~[:value].chomp
+            iterator.set_attribute($~[:key], value)
+          end
+        end
+
+        iterator.submodules_by_name
+      end
+
+      def reindex_by_path(submodules_by_name)
+        # Convert from an indexed by name to an array indexed by path
+        # If a submodule doesn't have a path, it is considered bogus
+        # and is ignored
+        submodules_by_name.each_with_object({}) do |(name, data), results|
+          path = data.delete 'path'
+          next unless path
+
+          results[path] = data
+        end
+      end
+    end
+  end
+end