scriptcs#1143. Char literals does not take escape sequences into account (scriptcs#1144)

rickardp · glennblock · commit 2ed8e70e101d · 2017-01-02T18:01:52.000-08:00
* scriptcs#1143: Char literals does not take escape sequences into account * scriptcs#1143: Added unit test for problem and added a fix to not break another unit test that is checking that broken input is to be accepted
diff --git a/src/ScriptCs.Engine.Mono/Segmenter/Lexer/ScriptLexer.cs b/src/ScriptCs.Engine.Mono/Segmenter/Lexer/ScriptLexer.cs
@@ -72,14 +72,18 @@ public LexerResult GetToken()
                 string @char = string.Empty;
                 @char += (char)_lastChar;
 
-                _lastChar = Read();
-                int count = 0;
-                while (count < 2 && _lastChar != Token.Eof)
+                int previous;
+                do
                 {
-                    count++;
-                    @char += (char)_lastChar;
+                    previous = _lastChar;
                     _lastChar = Read();
-                }
+					if(_lastChar != Token.Eof)
+                    	@char += (char)_lastChar;
+                } while (!(_lastChar == Token.SingleQuote && previous != Token.EscapeChar)
+                    && _lastChar != Token.Eof);
+
+				if(_lastChar != Token.Eof)
+					_lastChar = Read(); //eat
 
                 return new LexerResult
                 {
diff --git a/test/ScriptCs.Engine.Mono.Tests/Segmenter/ScriptLexerTests.cs b/test/ScriptCs.Engine.Mono.Tests/Segmenter/ScriptLexerTests.cs
@@ -129,6 +129,20 @@ public void ShouldIdenityCharactersAsToken()
                 token.TokenValue.ShouldEqual(Code);
             }
 
+            [Fact]
+            public void ShouldIdentifyEscapeSequencesInCharacterLiterals()
+            {
+                const string Code = "\'\\t\'";
+
+                var lexer = new ScriptLexer(Code);
+                var token = lexer.GetToken();
+
+                token.Token.ShouldEqual(Token.Character);
+                token.Start.ShouldEqual(0);
+                token.End.ShouldEqual(4);
+                token.TokenValue.ShouldEqual(Code);
+            }
+
             [Fact]
             public void ShouldNotFailOnIdentifyingCharactersAsToken()
             {
