Merge pull request #580 from Insti/Query_canonical-data_version

Add query for version of canonical data

Author: hilary

lib/generator/files.rb

@@ -2,6 +2,10 @@
 
 module Generator
   module Files
+    def self.read(filename)
+      File.read(filename) if File.exist?(filename)
+    end
+
     class Readable
       attr_reader :filename, :repository_root
       def initialize(filename:, repository_root: nil)
@@ -10,7 +14,7 @@ def initialize(filename:, repository_root: nil)
       end
 
       def to_s
-        File.read(filename) if File.exist?(filename)
+        Files.read(filename)
       end
 
       def abbreviated_commit_hash

lib/generator/files/metadata_files.rb

@@ -17,6 +17,9 @@ def exercise_metadata_path
     end
 
     class CanonicalDataFile < Readable
+      def version
+        JSON.parse(to_s)['version'] if to_s
+      end
     end
   end
 end

test/generator/files/metadata_files_test.rb

@@ -7,18 +7,31 @@ class MetadataFilesTest < Minitest::Test
         track: 'test/fixtures/xruby'
       )
 
-      class TestMetadataFiles
-        def initialize
-          @paths = FixturePaths
-          @exercise_name = 'alpha'
+      def test_canonical_data
+        subject = OpenStruct.new(paths: FixturePaths, exercise_name: 'unimportant')
+        subject.extend(MetadataFiles)
+        assert_instance_of CanonicalDataFile, subject.canonical_data
+      end
+    end
+
+    class CanonicalDataFileTest < Minitest::Test
+      def test_version_for_file_that_does_not_exist
+        subject = CanonicalDataFile.new(filename: 'nonexistant')
+        assert_nil subject.version
+      end
+
+      def test_version
+        subject = CanonicalDataFile.new(filename: 'has version key')
+        Files.stub(:read, '{"version": "1.2.3"}' ) do
+          assert_equal "1.2.3", subject.version
         end
-        attr_reader :paths, :exercise_name
-        include MetadataFiles
       end
 
-      def test_canonical_data
-        subject = TestMetadataFiles.new
-        assert_instance_of CanonicalDataFile, subject.canonical_data
+      def test_version_not_present
+        subject = CanonicalDataFile.new(filename: 'no version key')
+        Files.stub(:read, '{ "json": true }' ) do
+          assert_nil subject.version
+        end
       end
     end
   end

test/generator/files_test.rb

@@ -2,6 +2,24 @@
 
 module Generator
   module Files
+
+    class ReadTest < Minitest::Test
+      def test_read_existing_file
+        expected = 'content unimportant'
+        File.stub(:exist?, true) do
+          File.stub(:read, expected ) do
+            assert_equal expected, Files.read('pretend/this/exists')
+          end
+        end
+      end
+
+      def test_read_non_existing_file
+        File.stub(:exist?, false) do
+          assert_nil Files.read('pretend/this/does/not/exist')
+        end
+      end
+    end
+
     class ReadableTest < Minitest::Test
       def test_abbreviated_commit_hash
         mock_git_command = Minitest::Mock.new.expect :call, nil, ['path/.git', 'subdir/file']