Don't allow escaping newlines in single line strings.

dart/frog/leg/scanner/scanner.dart

-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 interface Scanner {
   Token tokenize();
 }
 
 /**
  * Common base class for a Dart scanner.
  */
@@ skipping 617 matching lines @@
     }
   }
 
   static bool isHexDigit(int character) {
     if ($0 <= character && character <= $9) return true;
     character |= 0x20;
     return ($a <= character && character <= $f);
   }
 
   int tokenizeSingleLineString(int next, int q1, int start) {
-    while (next !== $EOF) {
-      if (next === q1) {
-        appendByteStringToken(STRING_INFO, utf8String(start, 0));
-        return advance();
-      } else if (next === $BACKSLASH) {
+    while (next !== q1) {
+      if (next === $BACKSLASH) {
         next = advance();
-        if (next === $EOF) {
-          throw new MalformedInputException("unterminated string literal",
-                                            charOffset);
-        }
       } else if (next === $$) {
-        beginToken();
-        next = advance();
-        if (next === $OPEN_CURLY_BRACKET) {
-          next = tokenizeInterpolatedExpression(next, start);
-        } else {
-          next = tokenizeInterpolatedIdentifier(next, start);
-        }
+        next = tokenizeStringInterpolation(start);
         start = byteOffset;
         continue;
-      } else if (next === $LF || next === $CR) {
+      }
+      if (next <= $CR && (next === $LF || next === $CR || next === $EOF)) {
         throw new MalformedInputException("unterminated string literal",
                                           charOffset);
       }
       next = advance();
     }
-    throw new MalformedInputException("unterminated string literal",
-                                      charOffset);
+    appendByteStringToken(STRING_INFO, utf8String(start, 0));
+    return advance();
+  }
+
+  int tokenizeStringInterpolation(int start) {
+    beginToken();
+    int next = advance();
+    if (next === $OPEN_CURLY_BRACKET) {
+      return tokenizeInterpolatedExpression(next, start);
+    } else {
+      return tokenizeInterpolatedIdentifier(next, start);
+    }
   }
 
   int tokenizeInterpolatedExpression(int next, int start) {
     appendByteStringToken(STRING_INFO, utf8String(start, -2));

[Lasse Reichstein Nielsen, 2012/01/26 19:19:19]

Consider moving this line and the identical one from ..Identifier to the above
method.
Maybe even the appendBeginGroup call.

[ahe, 2012/01/26 19:30:28]

Good suggestion, I'll look into that later. I don't want to rerun benchmarks :-)

     appendBeginGroup(STRING_INTERPOLATION_INFO, "\${");
     next = advance();
     while (next !== $EOF && next !== $STX) {
       next = bigSwitch(next);
     }
     if (next === $EOF) return next;
     return advance();
   }
 
   int tokenizeInterpolatedIdentifier(int next, int start) {
@@ skipping 40 matching lines @@
     return next;
   }
 }
 
 class MalformedInputException {
   final String message;
   final position;
   MalformedInputException(this.message, this.position);
   toString() => message;
 }