Add ToString to StackFrame and DeminifyStackTraceResult to make printing a deminified stack trace easy (#71)

README.md

@@ -144,7 +144,8 @@ The top level API for call stack deminification is the `StackTraceDeminifier.Dem
 
 ```csharp
 StackTraceDeminifier sourceMapCallstackDeminifier = StackTraceDeminfierFactory.GetStackTraceDeminfier(new SourceMapProvider(), new SourceCodeProvider());
-DeminifyStackTraceResult deminifyStackTraceResult = sourceMapCallstackDeminifier.DeminifyStackTrace(callstack)
+DeminifyStackTraceResult deminifyStackTraceResult = sourceMapCallstackDeminifier.DeminifyStackTrace(callstack);
+string deminifiedCallstack = deminifyStackTraceResult.ToString();
 ```
 
 The result of `DeminifyStackTrace` is a `DeminifyStackTraceResult`, which is an object that contains a list of `StackFrameDeminificationResults` which contains the parsed minified `StackFrame` objects in the `MinifiedStackFrame` property and an enum indicating if any errors occured when attempting to deminify the `StackFrame`. The `DeminifiedStackFrame` property contains the best guess `StackFrame` object that maps to the `MinifiedStackFrame` element with the same index. Note that any of the properties on a `StackTrace` object may be null if no value could be extracted from the input callstack string or source map.

src/SourceMapToolkit.CallstackDeminifier/DeminifyStackTraceResult.cs

@@ -1,11 +1,28 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 
 namespace SourcemapToolkit.CallstackDeminifier
 {
 	public class DeminifyStackTraceResult
 	{
+		public string Message;
+
 		public List<StackFrame> MinifiedStackFrames;
 
 		public List<StackFrameDeminificationResult> DeminifiedStackFrameResults;
+
+		public override string ToString()
+		{
+			string output = Message ?? string.Empty;
+			for (int i = 0; i < DeminifiedStackFrameResults.Count; i++)
+			{
+				StackFrame deminFrame = DeminifiedStackFrameResults[i].DeminifiedStackFrame;
+				StackFrame frame = string.IsNullOrEmpty(deminFrame.MethodName) ? MinifiedStackFrames[i] : deminFrame;
+
+				output += $"{Environment.NewLine}  {frame}";
+			}
+
+			return output;
+		}
 	}
 }

src/SourceMapToolkit.CallstackDeminifier/IStackTraceParser.cs

@@ -15,6 +15,22 @@ namespace SourcemapToolkit.CallstackDeminifier
 		/// Any parts of the stack trace that could not be parsed are excluded from
 		/// the result. Does not ever return null.
 		/// </returns>
+		/// <remarks>
+		/// This override drops the Message out param for backward compatibility
+		/// </remarks>
 		List<StackFrame> ParseStackTrace(string stackTraceString);
+
+		/// <summary>
+		/// Generates a list of StackFrame objects based on the input stack trace.
+		/// This method normalizes differences between different browsers.
+		/// The source positions in the parsed stack frames will be normalized so they
+		/// are zero-based instead of one-based to align with the rest of the library.
+		/// </summary>
+		/// <returns>
+		/// Returns a list of StackFrame objects corresponding to the stackTraceString.
+		/// Any parts of the stack trace that could not be parsed are excluded from
+		/// the result. Does not ever return null.
+		/// </returns>
+		List<StackFrame> ParseStackTrace(string stackTraceString, out string message);
 	}
 }

src/SourceMapToolkit.CallstackDeminifier/StackFrame.cs

@@ -21,5 +21,19 @@ namespace SourcemapToolkit.CallstackDeminifier
 		/// The zero-based position of this stack entry.
 		/// </summary>
 		public SourcePosition SourcePosition { get; set; }
+
+		public override string ToString()
+		{
+			string output = $"at {(string.IsNullOrWhiteSpace(MethodName) ? "?" : MethodName)}";
+			if (!string.IsNullOrWhiteSpace(FilePath))
+			{
+				output += $" in {FilePath}";
+				if (SourcePosition != null)
+				{
+					output += $":{SourcePosition.ZeroBasedLineNumber}:{SourcePosition.ZeroBasedColumnNumber}";
+				}
+			}
+			return output;
+		}
 	}
 }

src/SourceMapToolkit.CallstackDeminifier/StackTraceDeminifier.cs

@@ -24,7 +24,8 @@ namespace SourcemapToolkit.CallstackDeminifier
 		public DeminifyStackTraceResult DeminifyStackTrace(string stackTraceString)
 		{
 			DeminifyStackTraceResult result = new DeminifyStackTraceResult();
-			result.MinifiedStackFrames = _stackTraceParser.ParseStackTrace(stackTraceString);
+			result.MinifiedStackFrames = _stackTraceParser.ParseStackTrace(stackTraceString, out string message);
+			result.Message = message;
 			result.DeminifiedStackFrameResults = new List<StackFrameDeminificationResult>();
 
 			foreach (StackFrame minifiedStackFrame in result.MinifiedStackFrames)

src/SourceMapToolkit.CallstackDeminifier/StackTraceParser.cs

@@ -26,16 +26,43 @@ namespace SourcemapToolkit.CallstackDeminifier
 		/// Any parts of the stack trace that could not be parsed are excluded from
 		/// the result. Does not ever return null.
 		/// </returns>
+		/// <remarks>
+		/// This override drops the Message out param for backward compatibility
+		/// </remarks>
 		public List<StackFrame> ParseStackTrace(string stackTraceString)
+		{
+			return ParseStackTrace(stackTraceString, out string message);
+		}
+
+		/// <summary>
+		/// Generates a list of StackFrame objects based on the input stack trace.
+		/// This method normalizes differences between different browsers.
+		/// The source positions in the parsed stack frames will be normalized so they
+		/// are zero-based instead of one-based to align with the rest of the library.
+		/// </summary>
+		/// <returns>
+		/// Returns a list of StackFrame objects corresponding to the stackTraceString.
+		/// Any parts of the stack trace that could not be parsed are excluded from
+		/// the result. Does not ever return null.
+		/// </returns>
+		public List<StackFrame> ParseStackTrace(string stackTraceString, out string message)
 		{
 			if (stackTraceString == null)
 			{
 				throw new ArgumentNullException(nameof(stackTraceString));
 			}
 
+			message = null;
 			List<StackFrame> stackTrace = new List<StackFrame>();
 			List<string> stackFrameStrings = stackTraceString.Split('\n').ToList();
 
+			var firstFrame = stackFrameStrings.First();
+			if (!firstFrame.StartsWith(" ") && TryExtractMethodNameFromFrame(firstFrame) == null)
+			{
+				message = firstFrame.Trim();
+				stackFrameStrings.RemoveAt(0);
+			}
+
 			foreach (string frame in stackFrameStrings)
 			{
 				StackFrame parsedStackFrame = TryParseSingleStackFrame(frame);

tests/SourcemapToolkit.CallstackDeminifier.UnitTests/StackTraceDeminifierEndToEndTests.cs

@@ -112,5 +112,33 @@ window.onload/<@http://localhost:11323/crashcauser.min.js:1:445";
             // Assert
             ValidateDeminifyStackTraceResults(results);
         }
-    }
+
+		[Fact]
+		public void DeminifyResultToString_SuccessfullyDeminified_AllLinesDeminified()
+		{
+			// Arrange
+			StackTraceDeminifier stackTraceDeminifier = GetStackTraceDeminifierWithDependencies();
+			string ieStackTrace = @"TypeError: Unable to get property 'length' of undefined or null reference
+   at Anonymous function (http://localhost:11323/crashcauser.min.js:1:112)
+   at i (http://localhost:11323/crashcauser.min.js:1:95)
+   at t (http://localhost:11323/crashcauser.min.js:1:75)
+   at n (http://localhost:11323/crashcauser.min.js:1:50)
+   at causeCrash (http://localhost:11323/crashcauser.min.js:1:341)
+   at Anonymous function (http://localhost:11323/crashcauser.min.js:1:445)";
+			DeminifyStackTraceResult results = stackTraceDeminifier.DeminifyStackTrace(ieStackTrace);
+			string exectedResult = @"TypeError: Unable to get property 'length' of undefined or null reference
+  at level3 in crashcauser.js:16:12
+  at level3 in crashcauser.js:14:9
+  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";
+
+			// Act
+			string formatted = results.ToString();
+
+			// Assert
+			Assert.Equal(exectedResult, formatted);
+		}
+	}
 }