Fix handling of CRLF line endings in Script::GetSnippet.

runtime/vm/object.cc

 // 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.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 7415 matching lines @@
 
 
 RawString* Script::GetSnippet(intptr_t from_line,
                               intptr_t from_column,
                               intptr_t to_line,
                               intptr_t to_column) const {
   const String& src = String::Handle(Source());
   intptr_t length = src.Length();
   intptr_t line = 1 + line_offset();
   intptr_t column = 1;
-  intptr_t lookahead = 0;
+  intptr_t scan_position = 0;
   intptr_t snippet_start = -1;
   intptr_t snippet_end = -1;
   if (from_line - line_offset() == 1) {
     column += col_offset();
   }
-  char c = src.CharAt(lookahead);
-  while (lookahead != length) {
-    if (snippet_start == -1) {
-      if ((line == from_line) && (column == from_column)) {
-        snippet_start = lookahead;
-      }
-    } else if ((line == to_line) && (column == to_column)) {
-      snippet_end = lookahead;
-      break;
-    }
+
+  while (scan_position != length) {
+    char c = src.CharAt(scan_position);
     if (c == '\n') {
       line++;
       column = 0;
+    } else if (c == '\r') {
+      line++;
+      column = 0;
+      if ((scan_position + 1 != length) &&
+          (src.CharAt(scan_position + 1) == '\n')) {
+        scan_position++;
+      }
     }
+    scan_position++;
     column++;
-    lookahead++;
-    if (lookahead != length) {
-      // Replace '\r' with '\n' and a sequence of '\r' '\n' with a single '\n'.
-      if (src.CharAt(lookahead) == '\r') {
-        c = '\n';
-        if (lookahead + 1 != length && src.CharAt(lookahead) == '\n') {
-          lookahead++;
-        }
-      } else {
-        c = src.CharAt(lookahead);
+
+    if (snippet_start == -1) {
+      if ((line == from_line) && (column == from_column)) {
+        snippet_start = scan_position;
       }
+    } else if ((line == to_line) && (column == to_column)) {
+      snippet_end = scan_position;
+      break;
     }
   }
   String& snippet = String::Handle();
   if ((snippet_start != -1) && (snippet_end != -1)) {
     snippet =
         String::SubString(src, snippet_start, snippet_end - snippet_start);
   }
   return snippet.raw();
 }
 
@@ skipping 9744 matching lines @@
   return "_MirrorReference";
 }
 
 
 void MirrorReference::PrintToJSONStream(JSONStream* stream, bool ref) const {
   Instance::PrintToJSONStream(stream, ref);
 }
 
 
 }  // namespace dart