Better method name parsing and mapping (#76)

* Fix method name association, add Webpack + TypeScript example test

.gitignore

@@ -266,4 +266,6 @@ __pycache__/
 
 # Minified JavaScript
 *.min.js
-*.min.js.map
+*.min.js.map
+
+!**/webpackapp/**

src/SourceMapToolkit.CallstackDeminifier/FunctionFinderVisitor.cs

@@ -49,7 +49,7 @@ namespace SourcemapToolkit.CallstackDeminifier
 			BinaryOperator parentBinaryOperator = node.Parent as BinaryOperator;
 			if (parentBinaryOperator != null)
 			{
-				result.Add(ExtractBindingsFromBinaryOperator(parentBinaryOperator));
+				result.AddRange(ExtractBindingsFromBinaryOperator(parentBinaryOperator));
 				return result;
 			}
 
@@ -61,7 +61,7 @@ namespace SourcemapToolkit.CallstackDeminifier
 				ObjectLiteral objectLiteralParent = parentObjectLiteralProperty.Parent?.Parent as ObjectLiteral;
 				if (objectLiteralParent != null && objectLiteralParent.Parent is BinaryOperator)
 				{
-					result.Add(ExtractBindingsFromBinaryOperator((BinaryOperator)objectLiteralParent.Parent));
+					result.AddRange(ExtractBindingsFromBinaryOperator((BinaryOperator)objectLiteralParent.Parent));
 				}
 				
 				result.Add(
@@ -110,15 +110,47 @@ namespace SourcemapToolkit.CallstackDeminifier
 			return null;
 		}
 
-		private BindingInformation ExtractBindingsFromBinaryOperator(BinaryOperator parentBinaryOperator)
+		private IEnumerable<BindingInformation> ExtractBindingsFromBinaryOperator(BinaryOperator parentBinaryOperator)
+		{
+			// If the operand has a dot in the name it's a Member. e.g. a.b, a.prototype, a.prototype.b
+			Member member = parentBinaryOperator.Operand1 as Member;
+			if (member != null)
+			{
+				// Split members into two parts, on the last dot, so a.prototype.b becomes [a.prototype, b]
+				// This separates the generated location for the property/method name (b), and allows deminification
+				// to resolve both the class and method names.
+				yield return ExtractBindingsFromNode(member.Root);
+
+				// a.prototype splits into [a, prototype], but we throw away the prototype as this doesn't map to anything useful in the original source
+				if (member.Name != "prototype")
+				{
+					int offset = member.NameContext.Code.StartsWith(".") ? 1 : 0;
+					yield return new BindingInformation
+					{
+						Name = member.Name,
+						SourcePosition = new SourcePosition
+						{
+							ZeroBasedLineNumber = member.NameContext.StartLineNumber - 1,
+							ZeroBasedColumnNumber = member.NameContext.StartColumn + offset
+						}
+					};
+				}
+			}
+			else
+			{
+				yield return ExtractBindingsFromNode(parentBinaryOperator.Operand1);
+			}
+		}
+
+		private BindingInformation ExtractBindingsFromNode(AstNode node)
 		{
 			return new BindingInformation
 			{
-				Name = parentBinaryOperator.Operand1.Context.Code,
+				Name = node.Context.Code,
 				SourcePosition = new SourcePosition
 				{
-					ZeroBasedLineNumber = parentBinaryOperator.Operand1.Context.StartLineNumber - 1,
-					ZeroBasedColumnNumber = parentBinaryOperator.Operand1.Context.StartColumn
+					ZeroBasedLineNumber = node.Context.StartLineNumber - 1,
+					ZeroBasedColumnNumber = node.Context.StartColumn
 				}
 			};
 		}

src/SourceMapToolkit.CallstackDeminifier/FunctionMapGenerator.cs

@@ -78,12 +78,11 @@ namespace SourcemapToolkit.CallstackDeminifier
 
 			if (wrappingFunction.Bindings != null && wrappingFunction.Bindings.Count > 0)
 			{
+				MappingEntry objectProtoypeMappingEntry = null;
 				if (wrappingFunction.Bindings.Count == 2)
 				{
-					MappingEntry objectProtoypeMappingEntry =
+					objectProtoypeMappingEntry =
 						sourceMap.GetMappingEntryForGeneratedSourcePosition(wrappingFunction.Bindings[0].SourcePosition);
-
-					methodName = objectProtoypeMappingEntry?.OriginalName;
 				}
 
 				MappingEntry mappingEntry =
@@ -91,9 +90,20 @@ namespace SourcemapToolkit.CallstackDeminifier
 
 				if (mappingEntry?.OriginalName != null)
 				{
-					if (methodName != null)
+					if (objectProtoypeMappingEntry?.OriginalName != null)
 					{
-						methodName = methodName + "." + mappingEntry.OriginalName;
+						string objectName = objectProtoypeMappingEntry.OriginalName;
+						if (objectProtoypeMappingEntry.OriginalSourcePosition?.ZeroBasedColumnNumber == mappingEntry.OriginalSourcePosition?.ZeroBasedColumnNumber
+							&& objectProtoypeMappingEntry.OriginalSourcePosition?.ZeroBasedLineNumber == mappingEntry.OriginalSourcePosition?.ZeroBasedLineNumber
+							&& objectName.EndsWith($".{mappingEntry.OriginalName}"))
+						{
+							// The object name already contains the method name, so do not append it
+							methodName = objectName;
+						}
+						else
+						{
+							methodName = $"{objectName}.{mappingEntry.OriginalName}";
+						}
 					}
 					else
 					{

tests/SourcemapToolkit.CallstackDeminifier.UnitTests/FunctionMapGeneratorUnitTests.cs

@@ -190,7 +190,8 @@ namespace SourcemapToolkit.CallstackDeminifier.UnitTests
 			// Assert
 			Assert.Equal(2, functionMap.Count);
 
-			Assert.Equal("foo.bar", functionMap[0].Bindings[0].Name);
+			Assert.Equal("foo", functionMap[0].Bindings[0].Name);
+			Assert.Equal("bar", functionMap[0].Bindings[1].Name);
 			Assert.Equal(0, functionMap[0].Bindings[0].SourcePosition.ZeroBasedLineNumber);
 			Assert.Equal(23, functionMap[0].Bindings[0].SourcePosition.ZeroBasedColumnNumber);
 			Assert.Equal(0, functionMap[0].StartSourcePosition.ZeroBasedLineNumber);
@@ -220,7 +221,8 @@ namespace SourcemapToolkit.CallstackDeminifier.UnitTests
 			// Assert
 			Assert.Equal(2, functionMap.Count);
 
-			Assert.Equal("foo.prototype.bar", functionMap[0].Bindings[0].Name);
+			Assert.Equal("foo.prototype", functionMap[0].Bindings[0].Name);
+			Assert.Equal("bar", functionMap[0].Bindings[1].Name);
 			Assert.Equal(0, functionMap[0].Bindings[0].SourcePosition.ZeroBasedLineNumber);
 			Assert.Equal(23, functionMap[0].Bindings[0].SourcePosition.ZeroBasedColumnNumber);
 			Assert.Equal(0, functionMap[0].StartSourcePosition.ZeroBasedLineNumber);
@@ -250,7 +252,7 @@ namespace SourcemapToolkit.CallstackDeminifier.UnitTests
 			// Assert
 			Assert.Equal(2, functionMap.Count);
 
-			Assert.Equal("foo.prototype", functionMap[0].Bindings[0].Name);
+			Assert.Equal("foo", functionMap[0].Bindings[0].Name);
 			Assert.Equal(0, functionMap[0].Bindings[0].SourcePosition.ZeroBasedLineNumber);
 			Assert.Equal(23, functionMap[0].Bindings[0].SourcePosition.ZeroBasedColumnNumber);
 			Assert.Equal("bar", functionMap[0].Bindings[1].Name);
@@ -305,7 +307,8 @@ namespace SourcemapToolkit.CallstackDeminifier.UnitTests
 			// Assert
 			Assert.Equal(2, functionMap.Count);
 
-			Assert.Equal("foo.bar", functionMap[0].Bindings[0].Name);
+			Assert.Equal("foo", functionMap[0].Bindings[0].Name);
+			Assert.Equal("bar", functionMap[0].Bindings[1].Name);
 			Assert.Equal(0, functionMap[0].Bindings[0].SourcePosition.ZeroBasedLineNumber);
 			Assert.Equal(23, functionMap[0].Bindings[0].SourcePosition.ZeroBasedColumnNumber);
 			Assert.Equal(0, functionMap[0].StartSourcePosition.ZeroBasedLineNumber);
@@ -335,7 +338,8 @@ namespace SourcemapToolkit.CallstackDeminifier.UnitTests
 			// Assert
 			Assert.Equal(2, functionMap.Count);
 
-			Assert.Equal("foo.prototype.bar", functionMap[0].Bindings[0].Name);
+			Assert.Equal("foo.prototype", functionMap[0].Bindings[0].Name);
+			Assert.Equal("bar", functionMap[0].Bindings[1].Name);
 			Assert.Equal(0, functionMap[0].Bindings[0].SourcePosition.ZeroBasedLineNumber);
 			Assert.Equal(23, functionMap[0].Bindings[0].SourcePosition.ZeroBasedColumnNumber);
 			Assert.Equal(0, functionMap[0].StartSourcePosition.ZeroBasedLineNumber);
@@ -365,7 +369,7 @@ namespace SourcemapToolkit.CallstackDeminifier.UnitTests
 			// Assert
 			Assert.Equal(2, functionMap.Count);
 
-			Assert.Equal("foo.prototype", functionMap[0].Bindings[0].Name);
+			Assert.Equal("foo", functionMap[0].Bindings[0].Name);
 			Assert.Equal(0, functionMap[0].Bindings[0].SourcePosition.ZeroBasedLineNumber);
 			Assert.Equal(23, functionMap[0].Bindings[0].SourcePosition.ZeroBasedColumnNumber);
 			Assert.Equal("bar", functionMap[0].Bindings[1].Name);

tests/SourcemapToolkit.CallstackDeminifier.UnitTests/SourcemapToolkit.CallstackDeminifier.UnitTests.csproj

@@ -97,6 +97,7 @@
     <Compile Include="KeyValueCacheUnitTests.cs" />
     <Compile Include="StackFrameDeminifierUnitTests.cs" />
     <Compile Include="StackTraceDeminifierClosureEndToEndTests.cs" />
+    <Compile Include="StackTraceDeminifierWebpackEndToEndTests.cs" />
     <Compile Include="StackTraceDeminifierEndToEndTests.cs" />
     <Compile Include="StackTraceDeminifierUnitTests.cs" />
     <Compile Include="StackTraceParserUnitTests.cs" />
@@ -150,6 +151,13 @@
     <Error Condition="!Exists('..\..\packages\xunit.core.2.4.1\build\xunit.core.props')" Text="$([System.String]::Format('$(ErrorText)', '..\..\packages\xunit.core.2.4.1\build\xunit.core.props'))" />
     <Error Condition="!Exists('..\..\packages\xunit.core.2.4.1\build\xunit.core.targets')" Text="$([System.String]::Format('$(ErrorText)', '..\..\packages\xunit.core.2.4.1\build\xunit.core.targets'))" />
   </Target>
+  <Target Name="AfterBuild">
+    <ItemGroup>
+      <TestFiles Include="$(ProjectDir)webpackapp\*.*" />
+    </ItemGroup>
+    <Copy SourceFiles="@(TestFiles)" DestinationFolder="$(OutDir)webpackapp\">
+    </Copy>
+  </Target>
   <Import Project="..\..\packages\xunit.core.2.4.1\build\xunit.core.targets" Condition="Exists('..\..\packages\xunit.core.2.4.1\build\xunit.core.targets')" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.

tests/SourcemapToolkit.CallstackDeminifier.UnitTests/StackTraceDeminifierClosureEndToEndTests.cs

@@ -30,7 +30,7 @@ namespace SourcemapToolkit.CallstackDeminifier.UnitTests
 			Assert.Equal("mynamespace.objectWithMethods.propertyMethodLevel2", results.DeminifiedStackFrameResults[0].DeminifiedStackFrame.MethodName);
 			Assert.Equal("mynamespace.objectWithMethods.prototypeMethodLevel1", results.DeminifiedStackFrameResults[1].DeminifiedStackFrame.MethodName);
 			Assert.Equal("GlobalFunction", results.DeminifiedStackFrameResults[2].DeminifiedStackFrame.MethodName);
-			Assert.Equal("window", results.DeminifiedStackFrameResults[3].DeminifiedStackFrame.MethodName);
+			Assert.Equal("window.onload", results.DeminifiedStackFrameResults[3].DeminifiedStackFrame.MethodName);
 		}
 
 		[Fact]

tests/SourcemapToolkit.CallstackDeminifier.UnitTests/StackTraceDeminifierEndToEndTests.cs

@@ -31,7 +31,7 @@ namespace SourcemapToolkit.CallstackDeminifier.UnitTests
 			Assert.Equal("level2", results.DeminifiedStackFrameResults[2].DeminifiedStackFrame.MethodName);
 			Assert.Equal("level1", results.DeminifiedStackFrameResults[3].DeminifiedStackFrame.MethodName);
 			Assert.Equal("causeCrash", results.DeminifiedStackFrameResults[4].DeminifiedStackFrame.MethodName);
-			Assert.Equal("window", results.DeminifiedStackFrameResults[5].DeminifiedStackFrame.MethodName);
+			Assert.Equal("window.onload", results.DeminifiedStackFrameResults[5].DeminifiedStackFrame.MethodName);
 		}
 
 		[Fact]
@@ -132,7 +132,7 @@ window.onload/<@http://localhost:11323/crashcauser.min.js:1:445";
   at level2 in crashcauser.js:10:8
   at level1 in crashcauser.js:5:8
   at causeCrash in crashcauser.js:27:4
-  at window in crashcauser.js:32:8";
+  at window.onload in crashcauser.js:32:8";
 
 			// Act
 			string formatted = results.ToString();

tests/SourcemapToolkit.CallstackDeminifier.UnitTests/StackTraceDeminifierWebpackEndToEndTests.cs

@@ -0,0 +1,60 @@
+using Xunit;
+using System.IO;
+using System;
+
+namespace SourcemapToolkit.CallstackDeminifier.UnitTests
+{
+	public class WebpackTestProvider : ISourceMapProvider, ISourceCodeProvider
+	{
+		private static readonly string basePath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "webpackapp");
+
+		private StreamReader GetStreamOrNull(string fileName)
+		{
+			string filePath = Path.Combine(basePath, fileName);
+			if (File.Exists(filePath))
+			{
+				return new StreamReader(File.OpenRead(filePath));
+			}
+
+			return null;
+		}
+
+		public StreamReader GetSourceCode(string sourceUrl)
+		{
+			return GetStreamOrNull(Path.GetFileName(sourceUrl));
+		}
+
+		public StreamReader GetSourceMapContentsForCallstackUrl(string sourceUrl)
+		{
+			return GetStreamOrNull($"{Path.GetFileName(sourceUrl)}.map");
+		}
+	}
+
+	public class StackTraceDeminifierWebpackEndToEndTests
+	{
+        private StackTraceDeminifier GetStackTraceDeminifierWithDependencies()
+		{
+			var provider = new WebpackTestProvider();
+			return StackTraceDeminfierFactory.GetStackTraceDeminfier(provider, provider);
+        }
+
+		[Fact]
+		public void DeminifyStackTrace_MinifiedStackTrace_CorrectDeminificationWhenPossible()
+		{
+			// Arrange
+			StackTraceDeminifier stackTraceDeminifier = GetStackTraceDeminifierWithDependencies();
+			string chromeStackTrace = @"TypeError: Cannot read property 'nonExistantmember' of undefined
+    at t.onButtonClick (http://localhost:3000/js/bundle.ffe51781aee314a37903.min.js:1:3573)
+    at Object.sh (https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.6/umd/react-dom.production.min.js:164:410)";
+			string deminifiedStackTrace = @"TypeError: Cannot read property 'nonExistantmember' of undefined
+  at _this.onButtonClick in webpack:///./components/App.tsx:10:45
+  at Object.sh in https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.6/umd/react-dom.production.min.js:163:409";
+
+			// Act
+			DeminifyStackTraceResult results = stackTraceDeminifier.DeminifyStackTrace(chromeStackTrace);
+
+			// Assert
+			Assert.Equal(deminifiedStackTrace.Replace("\r", ""), results.ToString().Replace("\r", ""));
+		}
+	}
+}

tests/SourcemapToolkit.CallstackDeminifier.UnitTests/webpackapp/Readme.md

@@ -0,0 +1,5 @@
+# Example Webpack App Source
+
+This is an example of minified JS from a Webpack + TypeScript + React app.
+
+It was generated from https://github.com/vikpe/react-webpack-typescript-starter