Implement Equality

src/ParseDiff.Tests/ParseDiff.Tests.csproj

@@ -53,6 +53,7 @@
   <ItemGroup>
     <Compile Include="TestDiff.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="TestEquality.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\ParseDiff\ParseDiff.csproj">

src/ParseDiff.Tests/TestEquality.cs

@@ -0,0 +1,179 @@
+namespace ParseDiff.Tests
+{
+
+    using System;
+    using System.Linq;
+    using Microsoft.VisualStudio.TestTools.UnitTesting;
+    using static Microsoft.VisualStudio.TestTools.UnitTesting.Assert;
+
+    [TestClass]
+    public class TestEquality
+    {
+        [TestMethod]
+        public void SameDiffShouldBeEqual()
+        {
+            var diff = @"
+diff --git a/file b/file
+index 123..456 789
+--- a/file
++++ b/file
+@@ -1,2 +1,2 @@
+- line1
++ line2";
+
+            var files1 = Diff.Parse(diff, Environment.NewLine).ToArray();
+            var files2 = Diff.Parse(diff, Environment.NewLine).ToArray();
+
+            AreEqual(files1.First(), files2.First());
+            IsTrue(Enumerable.SequenceEqual(files1, files2));
+        }
+
+
+        [TestMethod]
+        public void DifferentDiffShouldNotBeEqual()
+        {
+            var diff1 = @"
+diff --git a/file b/file
+index 123..456 789
+--- a/file
++++ b/file
+@@ -1,2 +1,2 @@
+- line1
++ line2";
+
+            var diff2 = @"
+diff -r 514fc757521e lib/parsers.coffee
+--- a/lib/parsers.coffee	Thu Jul 09 00:56:36 2015 +0200
++++ b/lib/parsers.coffee	Fri Jul 10 16:23:43 2015 +0200
+@@ -43,6 +43,9 @@
+             files[file] = { added: added, deleted: deleted }
+         files
++    diff: (out) ->
++        files = {}
++
+ module.exports = Parsers
+ module.exports.version = (out) ->
+";
+            var files1 = Diff.Parse(diff1, Environment.NewLine).ToArray();
+            var files2 = Diff.Parse(diff2, Environment.NewLine).ToArray();
+
+            AreNotEqual(files1.First(), files2.First());
+            IsFalse(Enumerable.SequenceEqual(files1, files2));
+        }
+
+        [TestMethod]
+        public void DifferentChunksDiffShouldNotBeEqual()
+        {
+            var diff1 = @"
+diff -r 514fc757521e lib/parsers.coffee
+--- a/lib/parsers.coffee	Thu Jul 09 00:56:36 2015 +0200
++++ b/lib/parsers.coffee	Fri Jul 10 16:23:43 2015 +0200
+@@ -43,6 +43,9 @@
+             files[file] = { added: added, deleted: deleted }
+         files
++    diff: (out) ->
++        files = {}
++
+ module.exports = Parsers
+ module.exports.version = (out) ->
+";
+
+            var diff2 = @"
+diff -r 514fc757521e lib/parsers.coffee
+--- a/lib/parsers.coffee	Thu Jul 09 00:56:36 2015 +0200
++++ b/lib/parsers.coffee	Fri Jul 10 16:23:43 2015 +0200
+@@ -43,6 +43,9 @@
+             files[file] = { added: added, deleted: deleted }
+         files
++    diff: (out) ->
++  XXX   files = {}
++
+ module.exports = Parsers
+ module.exports.version = (out) ->
+";
+            var files1 = Diff.Parse(diff1, Environment.NewLine).ToArray();
+            var files2 = Diff.Parse(diff2, Environment.NewLine).ToArray();
+
+            AreNotEqual(files1.First(), files2.First());
+            IsFalse(Enumerable.SequenceEqual(files1, files2));
+        }
+
+        [TestMethod]
+        public void RebasedPatchesShouldBeEqual()
+        {
+            var patch1 = @"
+# HG changeset patch
+# User xxx
+# Date 1483371015 -3600
+#      Mon Jan 02 16:30:15 2017 +0100
+# Node ID e5c9a138e019a6c2851c2bcd7960046b65c0fa9f
+# Parent  b612ff73463ca19be65c7f1235c275bd011a9feb
+Change 111
+
+diff -r b612ff73463c -r e5c9a138e019 1.txt
+--- a/1.txt	Thu Dec 22 14:58:46 2016 +0100
++++ b/1.txt	Mon Jan 02 16:30:15 2017 +0100
+@@ -1,5 +1,5 @@
+ qwesfsafadsadsadsadsadsad
+-zxcxzczxcxc
++zxCHANGEzxcxc
+
+
+xxx
+";
+            var patch2 = @"
+# HG changeset patch
+# User xxx
+# Date 1483371015 -3600
+#      Mon Jan 02 16:30:15 2017 +0100
+# Node ID 43339e170990fe2873b2866d5d916b6ec3ae0956
+# Parent  4afd4b93aa45455be267d5e4541094daea9b02f3
+Change 111
+
+diff -r 4afd4b93aa45 -r 43339e170990 1.txt
+--- a/1.txt	Thu Dec 22 14:59:09 2016 +0100
++++ b/1.txt	Mon Jan 02 16:30:15 2017 +0100
+@@ -1,5 +1,5 @@
+ qwesfsafadsadsadsadsadsad
+-zxcxzczxcxc
++zxCHANGEzxcxc
+
+
+xxx
+";
+
+            var files1 = Diff.Parse(patch1).ToArray();
+            var files2 = Diff.Parse(patch2).ToArray();
+
+            AreEqual(files1.First(), files2.First());
+            IsTrue(Enumerable.SequenceEqual(files1, files2));
+        }
+
+            [TestMethod]
+        public void DifferentIndexesShouldNotBeEqual()
+        {
+            var diffWithIndexLine = @"
+diff --git a/file b/file
+index 123..456 789
+--- a/file
++++ b/file
+@@ -1,2 +1,2 @@
+- line1
++ line2";
+            var diffWithNoIndexLine = @"
+diff --git a/file b/file
+--- a/file
++++ b/file
+@@ -1,2 +1,2 @@
+- line1
++ line2";
+
+            var files1 = Diff.Parse(diffWithIndexLine, Environment.NewLine).ToArray();
+            var files2 = Diff.Parse(diffWithNoIndexLine, Environment.NewLine).ToArray();
+
+            AreNotEqual(files1.First(), files2.First());
+            AreNotEqual(files2.First(), files1.First());
+            IsFalse(Enumerable.SequenceEqual(files1, files2));
+        }
+    }
+}

src/ParseDiff/ChunkDiff.cs

@@ -1,8 +1,10 @@
 namespace ParseDiff
 {
+    using System;
     using System.Collections.Generic;
+    using System.Linq;
 
-    public class ChunkDiff
+    public class ChunkDiff : IEquatable<ChunkDiff>
     {
         public ChunkDiff(string content, int oldStart, int oldLines, int newStart, int newLines)
         {
@@ -24,5 +26,36 @@ public ChunkDiff(string content, int oldStart, int oldLines, int newStart, int n
         public int NewStart { get; }
 
         public int NewLines { get; }
+
+        public bool Equals(ChunkDiff other)
+        {
+            return
+                Equals(Content, other.Content) &&
+                Equals(OldStart, other.OldStart) &&
+                Equals(OldLines, other.OldLines) &&
+                Equals(NewStart, other.NewStart) &&
+                Equals(NewLines, other.NewLines) &&
+                Enumerable.SequenceEqual(Changes, other.Changes);
+        }
+
+        public override bool Equals(object obj)
+        {
+            return Equals(obj as ChunkDiff);
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked // Overflow is fine, just wrap
+            {
+                int hash = 17;
+                hash = hash * 23 + Content?.GetHashCode() ?? 0;
+                hash = hash * 23 + OldStart;
+                hash = hash * 23 + OldLines;
+                hash = hash * 23 + NewStart;
+                hash = hash * 23 + NewLines;
+                hash = hash * 23 + Changes.GetHashCode();
+                return hash;
+            }
+        }
     }
 }

src/ParseDiff/FileDiff.cs

@@ -5,7 +5,7 @@
     using System.Linq;
     using System.Text.RegularExpressions;
 
-    public class FileDiff
+    public class FileDiff : IEquatable<FileDiff>
     {
         public ICollection<ChunkDiff> Chunks { get; } = new List<ChunkDiff>();
 
@@ -188,5 +188,46 @@ private static string parseFileFallback(string s)
                 ? s.Substring(2) 
                 : s;
         }
+
+        public bool Equals(FileDiff other)
+        {
+            return
+                Equals(Deletions, other.Deletions) &&
+                Equals(Additions, other.Additions) &&
+                Equals(To, other.To) &&
+                Equals(From, other.From) &&
+                Equals(Type, other.Type) &&
+                IndexEquals(other.Index) &&
+                Enumerable.SequenceEqual(Chunks, other.Chunks);
+        }
+
+        private bool IndexEquals(IEnumerable<string> otherIndex)
+        {
+            return 
+                Index == null 
+                ? otherIndex == null                 
+                : (otherIndex != null && Enumerable.SequenceEqual(Index, otherIndex));
+        }
+
+        public override bool Equals(object obj)
+        {
+            return Equals(obj as FileDiff);
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked // Overflow is fine, just wrap
+            {
+                int hash = 17;
+                hash = hash * 23 + Deletions;
+                hash = hash * 23 + Additions;
+                hash = hash * 23 + To?.GetHashCode() ?? 0;
+                hash = hash * 23 + From?.GetHashCode() ?? 0;
+                hash = hash * 23 + Type.GetHashCode();
+                hash = hash * 23 + Index?.GetHashCode() ?? 0;
+                hash = hash * 23 + Chunks.GetHashCode();
+                return hash;
+            }
+        }
     }
 }

src/ParseDiff/LineDiff.cs

@@ -1,6 +1,8 @@
 namespace ParseDiff
 {
-    public class LineDiff
+    using System;
+
+    public class LineDiff : IEquatable<LineDiff>
     {
         public LineDiff(LineChangeType type, int index, string content)
         {
@@ -32,5 +34,34 @@ public LineDiff(int oldIndex, int newIndex, string content)
         public int NewIndex { get; }
 
         public LineChangeType Type { get; }
+
+        public bool Equals(LineDiff other)
+        {
+            return
+              Equals(Content, other.Content) &&
+              Equals(Index, other.Index) &&
+              Equals(OldIndex, other.OldIndex) &&
+              Equals(NewIndex, other.NewIndex) &&
+              Equals(Type, other.Type);
+        }
+
+        public override bool Equals(object obj)
+        {
+            return Equals(obj as LineDiff);
+        }
+
+        public override int GetHashCode()
+        {
+            unchecked // Overflow is fine, just wrap
+            {
+                int hash = 17;
+                hash = hash * 23 + Content?.GetHashCode() ?? 0;
+                hash = hash * 23 + Index;
+                hash = hash * 23 + OldIndex;
+                hash = hash * 23 + NewIndex;
+                hash = hash * 23 + Type.GetHashCode();
+                return hash;
+            }
+        }
     }
 }