[ruby/prism] Attach magic comments to the parse result

https://github.com/ruby/prism/commit/c7ef25a79a

3 files changed, 34 insertions, 7 deletions

diff --git a/lib/prism/ffi.rb b/lib/prism/ffi.rb
index 69b2b35bbb..cc7d94fb3f 100644
--- a/lib/prism/ffi.rb
+++ b/lib/prism/ffi.rb
@@ -234,11 +234,11 @@ module Prism
       loader = Serialize::Loader.new(source, buffer.read)
 
       tokens = loader.load_tokens
-      node, comments, errors, warnings = loader.load_nodes
+      node, comments, magic_comments, errors, warnings = loader.load_nodes
 
       tokens.each { |token,| token.value.force_encoding(loader.encoding) }
 
-      ParseResult.new([node, tokens], comments, errors, warnings, source)
+      ParseResult.new([node, tokens], comments, magic_comments, errors, warnings, source)
     end
   end
 
diff --git a/lib/prism/lex_compat.rb b/lib/prism/lex_compat.rb
index d0679db669..a17d4eaadd 100644
--- a/lib/prism/lex_compat.rb
+++ b/lib/prism/lex_compat.rb
@@ -818,7 +818,7 @@ module Prism
       # We sort by location to compare against Ripper's output
       tokens.sort_by!(&:location)
 
-      ParseResult.new(tokens, result.comments, result.errors, result.warnings, [])
+      ParseResult.new(tokens, result.comments, result.magic_comments, result.errors, result.warnings, [])
     end
   end
 
diff --git a/lib/prism/parse_result.rb b/lib/prism/parse_result.rb
index b5e6643e6d..fd2737b20c 100644
--- a/lib/prism/parse_result.rb
+++ b/lib/prism/parse_result.rb
@@ -137,7 +137,7 @@ module Prism
     end
 
     def self.null
-      new(0, 0)
+      new(nil, 0, 0)
     end
   end
 
@@ -166,6 +166,32 @@ module Prism
     end
   end
 
+  # This represents a magic comment that was encountered during parsing.
+  class MagicComment
+    attr_reader :key_loc, :value_loc
+
+    def initialize(key_loc, value_loc)
+      @key_loc = key_loc
+      @value_loc = value_loc
+    end
+
+    def key
+      key_loc.slice
+    end
+
+    def value
+      value_loc.slice
+    end
+
+    def deconstruct_keys(keys)
+      { key_loc: key_loc, value_loc: value_loc }
+    end
+
+    def inspect
+      "#<Prism::MagicComment @key=#{key.inspect} @value=#{value.inspect}>"
+    end
+  end
+
   # This represents an error that was encountered during parsing.
   class ParseError
     attr_reader :message, :location
@@ -206,18 +232,19 @@ module Prism
   # the AST, any comments that were encounters, and any errors that were
   # encountered.
   class ParseResult
-    attr_reader :value, :comments, :errors, :warnings, :source
+    attr_reader :value, :comments, :magic_comments, :errors, :warnings, :source
 
-    def initialize(value, comments, errors, warnings, source)
+    def initialize(value, comments, magic_comments, errors, warnings, source)
       @value = value
       @comments = comments
+      @magic_comments = magic_comments
       @errors = errors
       @warnings = warnings
       @source = source
     end
 
     def deconstruct_keys(keys)
-      { value: value, comments: comments, errors: errors, warnings: warnings }
+      { value: value, comments: comments, magic_comments: magic_comments, errors: errors, warnings: warnings }
     end
 
     def success?