Introduce blame options for rename tracking

8 files changed, 53 insertions, 6 deletions

diff --git a/LibGit2Sharp/BlameHunkCollection.cs b/LibGit2Sharp/BlameHunkCollection.cs
index 35b94552..1ee64b40 100644
--- a/LibGit2Sharp/BlameHunkCollection.cs
+++ b/LibGit2Sharp/BlameHunkCollection.cs
@@ -27,11 +27,21 @@ namespace LibGit2Sharp
             var rawopts = new GitBlameOptions
             {
                 version = 1,
+                FindOptions = new GitDiffFindOptions {
+                    Version = 1,
+                },
                 flags = options.Strategy.ToGitBlameOptionFlags(),
                 MinLine = (uint)options.MinLine,
                 MaxLine = (uint)options.MaxLine,
             };
 
+            if (options.FindNoRenames)
+                rawopts.FindOptions.Flags = GitDiffFindFlags.GIT_DIFF_FIND_NO_RENAMES;
+            else if (options.FindExactRenames)
+                rawopts.FindOptions.Flags = GitDiffFindFlags.GIT_DIFF_FIND_EXACT_MATCH_ONLY;
+            else
+                rawopts.FindOptions.Flags = GitDiffFindFlags.GIT_DIFF_FIND_RENAMES;
+
             if (options.StartingAt != null)
             {
                 rawopts.NewestCommit = repo.Committish(options.StartingAt).Oid;
diff --git a/LibGit2Sharp/BlameOptions.cs b/LibGit2Sharp/BlameOptions.cs
index c39a3f53..dfd0f41d 100644
--- a/LibGit2Sharp/BlameOptions.cs
+++ b/LibGit2Sharp/BlameOptions.cs
@@ -6,7 +6,7 @@
     public enum BlameStrategy
     {
         /// <summary>
-        /// Track renames of the file, but no block movement.
+        /// Track renames of the file using diff rename detection, but no block movement.
         /// </summary>
         Default,
 
@@ -58,5 +58,15 @@
         /// If this is set to 0, blame ends with the last line in the file.
         /// </summary>
         public int MaxLine { get; set; }
+
+        /// <summary>
+        /// Disables rename heuristics, only matching renames on unmodified files.
+        /// </summary>
+        public bool FindExactRenames { get; set; }
+
+        /// <summary>
+        /// Fully disable rename checking.
+        /// </summary>
+        public bool FindNoRenames { get; set; }
     }
 }
diff --git a/LibGit2Sharp/Core/GitBlame.cs b/LibGit2Sharp/Core/GitBlame.cs
index 9db27d25..8efc7570 100644
--- a/LibGit2Sharp/Core/GitBlame.cs
+++ b/LibGit2Sharp/Core/GitBlame.cs
@@ -44,6 +44,7 @@ namespace LibGit2Sharp.Core
     internal class GitBlameOptions
     {
         public uint version = 1;
+        public GitDiffFindOptions FindOptions;
         public GitBlameOptionFlags flags;
         public UInt16 MinMatchCharacters;
         public GitOid NewestCommit;
diff --git a/LibGit2Sharp/Core/GitDiff.cs b/LibGit2Sharp/Core/GitDiff.cs
index 4d1e9768..d3db05fc 100644
--- a/LibGit2Sharp/Core/GitDiff.cs
+++ b/LibGit2Sharp/Core/GitDiff.cs
@@ -333,6 +333,9 @@ namespace LibGit2Sharp.Core
         // turn on all finding features
         GIT_DIFF_FIND_ALL = (0x0ff),
 
+        // does no work trying to find renames
+        GIT_DIFF_FIND_NO_RENAMES = (1 << 8),
+
         // measure similarity ignoring leading whitespace (default)
         GIT_DIFF_FIND_IGNORE_LEADING_WHITESPACE = 0,
         // measure similarity ignoring all whitespace
@@ -350,9 +353,9 @@ namespace LibGit2Sharp.Core
     }
 
     [StructLayout(LayoutKind.Sequential)]
-    internal class GitDiffFindOptions
+    internal struct GitDiffFindOptions
     {
-        public uint Version = 1;
+        public uint Version;
         public GitDiffFindFlags Flags;
         public UInt16 RenameThreshold;
         public UInt16 RenameFromRewriteThreshold;
diff --git a/LibGit2Sharp/Core/NativeMethods.cs b/LibGit2Sharp/Core/NativeMethods.cs
index a1b5b5cf..713c2160 100644
--- a/LibGit2Sharp/Core/NativeMethods.cs
+++ b/LibGit2Sharp/Core/NativeMethods.cs
@@ -558,7 +558,12 @@ namespace LibGit2Sharp.Core
         [DllImport(libgit2)]
         internal static extern int git_diff_find_similar(
             DiffSafeHandle diff,
-            GitDiffFindOptions options);
+            IntPtr options);
+
+        [DllImport(libgit2)]
+        internal static extern int git_diff_find_similar(
+            DiffSafeHandle diff,
+            ref GitDiffFindOptions options);
 
         [DllImport(libgit2)]
         internal static extern UIntPtr git_diff_num_deltas(DiffSafeHandle diff);
diff --git a/LibGit2Sharp/Core/Proxy.cs b/LibGit2Sharp/Core/Proxy.cs
index 11b3ca20..7a3fc792 100644
--- a/LibGit2Sharp/Core/Proxy.cs
+++ b/LibGit2Sharp/Core/Proxy.cs
@@ -798,12 +798,18 @@ namespace LibGit2Sharp.Core
             }
         }
 
-        public static void git_diff_find_similar(DiffSafeHandle diff, GitDiffFindOptions options)
+        public static void git_diff_find_similar(DiffSafeHandle diff, IntPtr options)
         {
             int res = NativeMethods.git_diff_find_similar(diff, options);
             Ensure.ZeroResult(res);
         }
 
+        public static void git_diff_find_similar(DiffSafeHandle diff, GitDiffFindOptions options)
+        {
+            int res = NativeMethods.git_diff_find_similar(diff, ref options);
+            Ensure.ZeroResult(res);
+        }
+
         public static int git_diff_num_deltas(DiffSafeHandle diff)
         {
             return (int)NativeMethods.git_diff_num_deltas(diff);
diff --git a/LibGit2Sharp/Diff.cs b/LibGit2Sharp/Diff.cs
index 1e8d283c..8cc96e26 100644
--- a/LibGit2Sharp/Diff.cs
+++ b/LibGit2Sharp/Diff.cs
@@ -544,7 +544,7 @@ namespace LibGit2Sharp
             var similarityOptions = (compareOptions == null) ? null : compareOptions.Similarity;
             if (similarityOptions == null || similarityOptions.RenameDetectionMode == RenameDetectionMode.Default)
             {
-                Proxy.git_diff_find_similar(diffList, null);
+                Proxy.git_diff_find_similar(diffList, IntPtr.Zero);
                 return;
             }
 
@@ -555,6 +555,7 @@ namespace LibGit2Sharp
 
             var opts = new GitDiffFindOptions
             {
+                Version = 1,
                 RenameThreshold = (ushort)similarityOptions.RenameThreshold,
                 RenameFromRewriteThreshold = (ushort)similarityOptions.RenameFromRewriteThreshold,
                 CopyThreshold = (ushort)similarityOptions.CopyThreshold,
diff --git a/LibGit2Sharp/DiffModifiers.cs b/LibGit2Sharp/DiffModifiers.cs
index af9ccb75..2dd05e43 100644
--- a/LibGit2Sharp/DiffModifiers.cs
+++ b/LibGit2Sharp/DiffModifiers.cs
@@ -36,5 +36,16 @@ namespace LibGit2Sharp
         /// diffing against the working directory.
         /// </summary>
         IncludeIgnored = (1 << 4),
+
+        /// <summary>
+        /// Specifies that no rename heuristics will be used when checking for
+        /// renames, renames being matched only on unmodified renamed files.
+        /// </summary>
+        FindExactRenames = (1 << 5),
+
+        /// <summary>
+        /// Specifies that no renames will be searched for when running blame.
+        /// </summary>
+        FindNoRenames = (1 << 6),
     }
 }