Improved performance of debugging in ActiveScript modes

Author: Taritsyn

NuGet/MsieJavaScriptEngine.nuspec

@@ -12,7 +12,7 @@
 		<requireLicenseAcceptance>false</requireLicenseAcceptance>
 		<description>This library is a .NET wrapper for working with the JavaScript engines of Internet Explorer and Edge (JsRT versions of Chakra, ActiveScript version of Chakra and Classic JavaScript Engine). Project was based on the code of SassAndCoffee.JavaScript (http://github.com/paulcbetts/SassAndCoffee), Chakra Sample Hosts (http://github.com/panopticoncentral/chakra-host) and jsrt-dotnet (http://github.com/robpaveza/jsrt-dotnet).</description>
 		<summary>This library is a .NET wrapper for working with the JavaScript engines of Internet Explorer and Edge (JsRT versions of Chakra, ActiveScript version of Chakra and Classic JavaScript Engine).</summary>
-		<releaseNotes>Changed a implementation of the `Dispose` method.</releaseNotes>
+		<releaseNotes>Improved performance of debugging in ActiveScript modes.</releaseNotes>
 		<copyright>Copyright (c) 2012-2018 Andrey Taritsyn - http://www.taritsyn.ru</copyright>
 		<language>en-US</language>
 		<tags>JavaScript ECMAScript MSIE IE Edge Chakra</tags>

NuGet/readme.txt

@@ -21,7 +21,7 @@
    =============
    RELEASE NOTES
    =============
-   Changed a implementation of the `Dispose` method.
+   Improved performance of debugging in ActiveScript modes.
 
    ============
    PROJECT SITE

build.cmd

@@ -3,7 +3,7 @@
 setlocal
 set ORIGINAL_CURRENT_DIR=%cd%
 set KOREBUILD_DOTNET_CHANNEL=rel-1.0.0
-set KOREBUILD_DOTNET_VERSION=1.1.7
+set KOREBUILD_DOTNET_VERSION=1.1.11
 
 cd %~dp0
 

build.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 ORIGINAL_CURRENT_DIR=%cd%
 KOREBUILD_DOTNET_CHANNEL=rel-1.0.0
-KOREBUILD_DOTNET_VERSION=1.1.7
+KOREBUILD_DOTNET_VERSION=1.1.11
 
 repoFolder="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 cd $repoFolder

src/MsieJavaScriptEngine.Net4/MsieJavaScriptEngine.Net40.csproj

@@ -312,6 +312,9 @@
     <Compile Include="..\MsieJavaScriptEngine\Helpers\NumericHelpers.cs">
       <Link>Helpers\NumericHelpers.cs</Link>
     </Compile>
+    <Compile Include="..\MsieJavaScriptEngine\Helpers\TextHelpers.cs">
+      <Link>Helpers\TextHelpers.cs</Link>
+    </Compile>
     <Compile Include="..\MsieJavaScriptEngine\Helpers\TypeMappingHelpers.cs">
       <Link>Helpers\TypeMappingHelpers.cs</Link>
     </Compile>

src/MsieJavaScriptEngine/ActiveScript/Debugging/DebugDocument.cs

@@ -3,7 +3,8 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Runtime.InteropServices;
-using System.Text.RegularExpressions;
+
+using MsieJavaScriptEngine.Helpers;
 
 namespace MsieJavaScriptEngine.ActiveScript.Debugging
 {
@@ -13,11 +14,6 @@ namespace MsieJavaScriptEngine.ActiveScript.Debugging
 	internal sealed class DebugDocument : IDebugDocumentInfo, IDebugDocumentProvider, IDebugDocument,
 		IDebugDocumentText
 	{
-		/// <summary>
-		/// Regular expression for working with a line break
-		/// </summary>
-		private static readonly Regex _lineBreakRegex = new Regex("\r\n|\n|\r");
-
 		/// <summary>
 		/// Active Script wrapper
 		/// </summary>
@@ -84,31 +80,6 @@ public DebugDocument(IActiveScriptWrapper activeScriptWrapper,
 		}
 
 
-		/// <summary>
-		/// Finds a line break
-		/// </summary>
-		/// <param name="sourceCode">Source code</param>
-		/// <param name="startPosition">Position in the input string that defines the leftmost
-		/// position to be searched</param>
-		/// <param name="length">Number of characters in the substring to include in the search</param>
-		/// <param name="lineBreakPosition">Position of line break</param>
-		/// <param name="lineBreakLength">Length of line break</param>
-		private static void FindLineBreak(string sourceCode, int startPosition, int length,
-			out int lineBreakPosition, out int lineBreakLength)
-		{
-			Match lineBreakMatch = _lineBreakRegex.Match(sourceCode, startPosition, length);
-			if (lineBreakMatch.Success)
-			{
-				lineBreakPosition = lineBreakMatch.Index;
-				lineBreakLength = lineBreakMatch.Length;
-			}
-			else
-			{
-				lineBreakPosition = -1;
-				lineBreakLength = 0;
-			}
-		}
-
 		/// <summary>
 		/// Initializes a debug document
 		/// </summary>
@@ -126,7 +97,7 @@ private void Initialize()
 					documentStartPosition : lineBreakPosition + lineBreakLength;
 				int remainderLength = documentEndPosition - linePosition + 1;
 
-				FindLineBreak(_code, linePosition, remainderLength,
+				TextHelpers.FindNextLineBreak(_code, linePosition, remainderLength,
 					out lineBreakPosition, out lineBreakLength);
 
 				int lineLength = lineBreakPosition != -1 ? lineBreakPosition - linePosition : 0;

src/MsieJavaScriptEngine/Helpers/TextHelpers.cs

@@ -0,0 +1,54 @@
+#if !NETSTANDARD1_3
+using MsieJavaScriptEngine.Utilities;
+
+namespace MsieJavaScriptEngine.Helpers
+{
+	/// <summary>
+	/// Text helpers
+	/// </summary>
+	internal static class TextHelpers
+	{
+		/// <summary>
+		/// Array of characters used to find the next line break
+		/// </summary>
+		private static readonly char[] _nextLineBreakChars = new char[] { '\r', '\n' };
+
+
+		/// <summary>
+		/// Finds a next line break
+		/// </summary>
+		/// <param name="sourceText">Source text</param>
+		/// <param name="startPosition">Position in the input string that defines the leftmost
+		/// position to be searched</param>
+		/// <param name="length">Number of characters in the substring to include in the search</param>
+		/// <param name="lineBreakPosition">Position of line break</param>
+		/// <param name="lineBreakLength">Length of line break</param>
+		public static void FindNextLineBreak(string sourceText, int startPosition, int length,
+			out int lineBreakPosition, out int lineBreakLength)
+		{
+			lineBreakPosition = sourceText.IndexOfAny(_nextLineBreakChars, startPosition, length);
+			if (lineBreakPosition != -1)
+			{
+				lineBreakLength = 1;
+				char currentCharacter = sourceText[lineBreakPosition];
+
+				if (currentCharacter == '\r')
+				{
+					int nextCharacterPosition = lineBreakPosition + 1;
+					char nextCharacter;
+
+					if (sourceText.TryGetChar(nextCharacterPosition, out nextCharacter)
+						&& nextCharacter == '\n')
+					{
+						lineBreakLength = 2;
+					}
+				}
+			}
+			else
+			{
+				lineBreakLength = 0;
+			}
+		}
+	}
+}
+#endif

src/MsieJavaScriptEngine/Utilities/StringExtensions.cs

@@ -100,5 +100,39 @@ public static string CapitalizeFirstLetter(this string source)
 
 			return result;
 		}
+
+		/// <summary>
+		/// Gets a character at the specified index from the string.
+		/// A return value indicates whether the receiving succeeded.
+		/// </summary>
+		/// <param name="source">The source string</param>
+		/// <param name="index">The zero-based index of the character</param>
+		/// <param name="result">When this method returns, contains the character from the string,
+		/// if the receiving succeeded, or null character if the receiving failed.
+		/// The receiving fails if the index out of bounds.</param>
+		/// <returns>true if the character was received successfully; otherwise, false</returns>
+		public static bool TryGetChar(this string source, int index, out char result)
+		{
+			if (source == null)
+			{
+				throw new ArgumentNullException("source");
+			}
+
+			bool isSuccess;
+			int length = source.Length;
+
+			if (length > 0 && index >= 0 && index < length)
+			{
+				result = source[index];
+				isSuccess = true;
+			}
+			else
+			{
+				result = '\0';
+				isSuccess = false;
+			}
+
+			return isSuccess;
+		}
 	}
 }