Add fine-grained diff implementation to LiveEdit engine.

test/mjsunit/debug-liveedit-diff.js

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 13 matching lines @@
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // Flags: --expose-debug-as debug
 // Get the Debug object exposed from the debug context global object.
 
 Debug = debug.Debug
 
 function CheckCompareOneWay(s1, s2) {
-  var diff_array = Debug.LiveEdit.TestApi.CompareStringsLinewise(s1, s2);
+  var diff_array = Debug.LiveEdit.TestApi.CompareStrings(s1, s2);
 
   var pos1 = 0;
   var pos2 = 0;
   print("Compare:");
+  print("s1='" + s1 + "'");
+  print("s2='" + s2 + "'");
+  print("Diff:");
+  print("" + diff_array);
   for (var i = 0; i < diff_array.length; i += 3) {
     var similar_length = diff_array[i] - pos1;
     assertEquals(s1.substring(pos1, pos1 + similar_length),
                  s2.substring(pos2, pos2 + similar_length));
 
     print(s1.substring(pos1, pos1 + similar_length));
     pos1 += similar_length;
     pos2 += similar_length;
     print("<<< " + pos1 + " " + diff_array[i + 1]);
-    print(s1.substring(pos1, pos1 + diff_array[i + 1]));
+    print(s1.substring(pos1, diff_array[i + 1]));
     print("===");
-    print(s2.substring(pos2, pos2 + diff_array[i + 2]));
+    print(s2.substring(pos2, diff_array[i + 2]));
     print(">>> " + pos2 + " " + diff_array[i + 2]);
-    pos1 += diff_array[i + 1];
-    pos2 += diff_array[i + 2];
+    pos1 = diff_array[i + 1];
+    pos2 = diff_array[i + 2];
   }
   {
     // After last change
     var similar_length = s1.length - pos1;
     assertEquals(similar_length, s2.length - pos2);
     assertEquals(s1.substring(pos1, pos1 + similar_length),
                  s2.substring(pos2, pos2 + similar_length));
 
     print(s1.substring(pos1, pos1 + similar_length));
   }
   print("");
 }
 
+function CheckCompareOneWayPlayWithLF(s1, s2) {
+  var s1Oneliner = s1.replace(/\n/g, ' ');
+  var s2Oneliner = s2.replace(/\n/g, ' ');
+  CheckCompareOneWay(s1, s2);
+  CheckCompareOneWay(s1Oneliner, s2);
+  CheckCompareOneWay(s1, s2Oneliner);
+  CheckCompareOneWay(s1Oneliner, s2Oneliner);
+}
+
 function CheckCompare(s1, s2) {
-  CheckCompareOneWay(s1, s2);
-  CheckCompareOneWay(s2, s1);
+  CheckCompareOneWayPlayWithLF(s1, s2);
+  CheckCompareOneWayPlayWithLF(s2, s1);
 }
 
 CheckCompare("", "");
 
 CheckCompare("a", "b");
 
 CheckCompare(
     "yesterday\nall\nmy\ntroubles\nseemed\nso\nfar\naway",
     "yesterday\nall\nmy\ntroubles\nseem\nso\nfar\naway"
 );
@@ skipping 11 matching lines @@
 CheckCompare(
     "yesterday\nall\nmy\ntroubles\nseemed\nso\nfar\naway",
     "yesterday\nall\nmy\ntroubles\nseemed\nso\nfar\naway\n"
 );
 
 CheckCompare(
     "yesterday\nall\nmy\ntroubles\nseemed\nso\nfar\naway",
     "yesterday\nall\nmy\ntroubles\nseemed\nso\n"
 );