From e066d24efba9587a66cf9eb6221b4a38c513c26e Mon Sep 17 00:00:00 2001
From: Carlos Martín Nieto <cmn@dwim.me>
Date: Fri, 12 Jun 2015 19:10:00 +0200
Subject: Add DiffBlobs

This lets you diff two arbitrary blobs with arbitrary names.
---
 diff.go | 48 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

(limited to 'diff.go')

diff --git a/diff.go b/diff.go
index aa422fc..de56374 100644
--- a/diff.go
+++ b/diff.go
@@ -5,6 +5,7 @@ package git
 
 extern int _go_git_diff_foreach(git_diff *diff, int eachFile, int eachHunk, int eachLine, void *payload);
 extern void _go_git_setup_diff_notify_callbacks(git_diff_options* opts);
+extern int _go_git_diff_blobs(git_blob *old, const char *old_path, git_blob *new, const char *new_path, git_diff_options *opts, int eachFile, int eachHunk, int eachLine, void *payload);
 */
 import "C"
 import (
@@ -670,3 +671,50 @@ func (v *Repository) DiffIndexToWorkdir(index *Index, opts *DiffOptions) (*Diff,
 	}
 	return newDiffFromC(diffPtr), nil
 }
+
+// DiffBlobs performs a diff between two arbitrary blobs. You can pass
+// whatever file names you'd like for them to appear as in the diff.
+func DiffBlobs(oldBlob *Blob, oldAsPath string, newBlob *Blob, newAsPath string, opts *DiffOptions, fileCallback DiffForEachFileCallback, detail DiffDetail) error {
+	data := &diffForEachData{
+		FileCallback: fileCallback,
+	}
+
+	intHunks := C.int(0)
+	if detail >= DiffDetailHunks {
+		intHunks = C.int(1)
+	}
+
+	intLines := C.int(0)
+	if detail >= DiffDetailLines {
+		intLines = C.int(1)
+	}
+
+	handle := pointerHandles.Track(data)
+	defer pointerHandles.Untrack(handle)
+
+	var oldBlobPtr, newBlobPtr *C.git_blob
+	if oldBlob != nil {
+		oldBlobPtr = oldBlob.cast_ptr
+	}
+	if newBlob != nil {
+		newBlobPtr = newBlob.cast_ptr
+	}
+
+	oldBlobPath := C.CString(oldAsPath)
+	defer C.free(unsafe.Pointer(oldBlobPath))
+	newBlobPath := C.CString(newAsPath)
+	defer C.free(unsafe.Pointer(newBlobPath))
+
+	copts, _ := diffOptionsToC(opts)
+	defer freeDiffOptions(copts)
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
+	ecode := C._go_git_diff_blobs(oldBlobPtr, oldBlobPath, newBlobPtr, newBlobPath, copts, 1, intHunks, intLines, handle)
+	if ecode < 0 {
+		return MakeGitError(ecode)
+	}
+
+	return nil
+}
-- 
cgit v1.2.3