[Yaml] add tests for specific mapping keys

Author: xabbuh

Tests/InlineTest.php

@@ -420,4 +420,15 @@ public function testVeryLongQuotedStrings()
 
         $this->assertEquals($longStringWithQuotes, $arrayFromYaml['longStringWithQuotes']);
     }
+
+    public function testBooleanMappingKeysAreConvertedToStrings()
+    {
+        $this->assertSame(array('false' => 'foo'), Inline::parse('{false: foo}'));
+        $this->assertSame(array('true' => 'foo'), Inline::parse('{true: foo}'));
+    }
+
+    public function testTheEmptyStringIsAValidMappingKey()
+    {
+        $this->assertSame(array('' => 'foo'), Inline::parse('{ "": foo }'));
+    }
 }