Fix attribute support for the "binary" option

When the "binary" option is set to true the "diff" option is to be set
to false automatically.

CHANGELOG

+v 10.6.3
+  - When parsing Git attributes "diff" is now set to false whenever "binary" is set to true
+
 v 10.6.2
   - Fix parsing Git attributes defined using an absolute path

lib/gitlab_git/attributes.rb

@@ -57,28 +57,35 @@ module Gitlab
         values = {}
         dash = '-'
         equal = '='
+        binary = 'binary'
         string.split(/\s+/).each do |chunk|
           # Data such as "foo = bar" should be treated as "foo" and "bar" being
           # separate boolean attributes.
           next if chunk == equal
+          key = chunk
+
           # Input: "-foo"
           if chunk.start_with?(dash)
             key = chunk.byteslice(1, chunk.length - 1)
-
-            values[key] = false
+            value = false
           # Input: "foo=bar"
           elsif chunk.include?(equal)
             key, value = chunk.split(equal, 2)
-            values[key] = value
-
           # Input: "foo"
           else
-            values[chunk] = true
+            value = true
           end
+
+          values[key] = value
+
+          # When the "binary" option is set the "diff" option should be set to
+          # the inverse. If "diff" is later set it should overwrite the
+          # automatically set value.
+          values['diff'] = false if key == binary && value
         end
         values

spec/attributes_spec.rb

@@ -45,6 +45,16 @@ describe Gitlab::Git::Attributes do
         expect(subject.attributes('/foo.png')).
           to eq({ 'gitlab-language' => 'png' })
       end
+
+      context 'when the "binary" option is set for a path' do
+        it 'returns true for the "binary" option' do
+          expect(subject.attributes('test.binary')['binary']).to eq(true)
+        end
+
+        it 'returns false for the "diff" option' do
+          expect(subject.attributes('test.binary')['diff']).to eq(false)
+        end
+      end
     end
     context 'using a path without any attributes' do
@@ -73,7 +83,7 @@ describe Gitlab::Git::Attributes do
     # It's a bit hard to test for something _not_ being processed. As such we'll
     # just test the number of entries.
     it 'ignores any comments and empty lines' do
-      expect(subject.patterns.length).to eq(8)
+      expect(subject.patterns.length).to eq(9)
     end
     it 'does not parse anything when the attributes file does not exist' do
@@ -113,7 +123,7 @@ describe Gitlab::Git::Attributes do
   describe '#each_line' do
     it 'iterates over every line in the attributes file' do
-      args = [String] * 12 # the number of lines in the file
+      args = [String] * 13 # the number of lines in the file
       expect { |b| subject.each_line(&b) }.to yield_successive_args(*args)
     end

spec/support/seed_helper.rb

@@ -55,6 +55,7 @@ module SeedHelper
 foo/bar.* foo
 *.cgi     key=value?p1=v1&p2=v2
 /*.png    gitlab-language=png
+*.binary  binary
 # This uses a tab instead of spaces to ensure the parser also supports this.
 *.md\tgitlab-language=markdown