Update OriginalPositionFor to match mozilla/source-map

Remove check where line and column number of found mapping must match
Change line number to be 1-based instead of 0-based

Author: sleeuwen

SourceMaps.StackTraces/StackTraceParser.cs

@@ -28,7 +28,7 @@ public static string ReTrace(SourceMapCollection sourceMaps, string stacktrace,
                 if (frame.LineNumber == null || frame.ColumnNumber == null)
                     continue;
 
-                var originalPosition = sourceMap?.OriginalPositionFor(frame.LineNumber.Value - 1, frame.ColumnNumber.Value - 1);
+                var originalPosition = sourceMap?.OriginalPositionFor(frame.LineNumber.Value, frame.ColumnNumber.Value - 1);
                 if (originalPosition == null)
                     continue;
 

SourceMaps.Tests/SourceMapParserTests.cs

@@ -138,7 +138,7 @@ public void Parse_OriginalPositionFor()
                 }
             };
 
-            var pos = map.OriginalPositionFor(2, 2).Value;
+            var pos = map.OriginalPositionFor(3, 2).Value;
             Assert.Equal("foo/bar/bang.coffee", pos.OriginalFileName);
             Assert.Equal(1, pos.OriginalLineNumber);
             Assert.Equal(1, pos.OriginalColumnNumber);

SourceMaps/SourceMap.cs

@@ -33,34 +33,35 @@ public sealed class SourceMap
         /// Returns the original source, line and column information for the generated
         /// source's line and column positions provided.
         /// </summary>
-        /// <param name="generatedLineNumber">The zero-based line number in the generated source, 1-based.</param>
-        /// <param name="generatedColumnNumber">The zero-based column number in the generated source, 0-based</param>
+        /// <param name="generatedLineNumber">The one-based line number in the generated source.</param>
+        /// <param name="generatedColumnNumber">The zero-based column number in the generated source</param>
         /// <returns>A struct with the original mappings, or null if no mapping exit for the given line and column number.</returns>
         public SourceMapMappingEntry? OriginalPositionFor(int generatedLineNumber, int generatedColumnNumber)
         {
             if (Mappings == null)
                 return null;
 
-            var index = Mappings.BinarySearch(
-                new SourceMapMappingEntry(generatedLineNumber, generatedColumnNumber, null, null, null, null),
-                Comparer<SourceMapMappingEntry>.Create((a, b) =>
-                {
-                    var lineNumberComparison = a.GeneratedLineNumber.CompareTo(b.GeneratedLineNumber);
-                    if (lineNumberComparison != 0) return lineNumberComparison;
-                    return a.GeneratedColumnNumber.CompareTo(b.GeneratedColumnNumber);
-                }));
+            var searchEntry = new SourceMapMappingEntry(generatedLineNumber - 1, generatedColumnNumber, null, null, null, null);
+            var index = Mappings.BinarySearch(searchEntry, MappingEntryComparer);
 
             if (index < 0)
             {
-                if (~index - 1 >= 0 &&
-                    Mappings[~index - 1].GeneratedLineNumber == generatedLineNumber &&
-                    Mappings[~index - 1].GeneratedColumnNumber == generatedColumnNumber)
+                if (~index - 1 >= 0)
                 {
                     index = ~index - 1;
                 }
             }
 
             return index >= 0 ? Mappings[index] : (SourceMapMappingEntry?)null;
         }
+
+        private static readonly IComparer<SourceMapMappingEntry> MappingEntryComparer = Comparer<SourceMapMappingEntry>.Create((a, b) =>
+        {
+            var lineNumberCompare = a.GeneratedLineNumber.CompareTo(b.GeneratedLineNumber);
+            if (lineNumberCompare != 0)
+                return lineNumberCompare;
+
+            return a.GeneratedColumnNumber.CompareTo(b.GeneratedColumnNumber);
+        });
     }
 }