Add support for getting blame information per issue #11

.gitignore

@@ -5,3 +5,4 @@
 *.log
 *~
 .node-version
+.DS_Store

README.md

@@ -358,3 +358,13 @@ associated with `path`.
 `path` - A repository-relative string path.
 
 Raises an `Error` if the path isn't readable or if another exception occurs.
+
+### Repository.getBlame(path)
+
+Gets the blame information of a given path.
+
+`path` - A repository-relative string path.
+
+Raises an `Error` if the path isn't readable or if another exception occurs.
+
+Returns an array of objects with `commitId`, `signature`, `startLineNumber` and `linesInHunk` keys.

spec/fixtures/blame.git/HEAD

@@ -0,0 +1 @@
+ref: refs/heads/master

spec/fixtures/blame.git/objects/a2/e56f1240cf8ee6fb4912b1fcb631a5d8254d46

@@ -0,0 +1 @@
+x
5���0�3�O�1=b)�;"��@�t��[����a���Rot�L6�U<��_U'�S�$.�TPD9\�����ό��)v�����%

spec/fixtures/blame.git/refs/heads/master

@@ -0,0 +1 @@
+fcfc9307b3c7864cbb8bbfe457f44d7a33202de4

spec/git-spec.coffee

@@ -724,3 +724,24 @@ describe "git", ->
 
     it "throws an error if the file doesn't exist", ->
       expect(-> repo.add('missing.txt')).toThrow()
+
+  describe ".getBlame(path)", ->
+    beforeEach ->
+      repoDirectory = temp.mkdirSync('node-git-repo-')
+      wrench.copyDirSyncRecursive(path.join(__dirname, 'fixtures/blame.git'), path.join(repoDirectory, '.git'))
+      repo = git.open(repoDirectory)
+
+    it "returns the blame for the path", ->
+      blame = repo.getBlame('a.txt')
+
+      expect(blame.length).toBe 1
+      expect(blame[0].commitId).toBe 'fcfc9307b'
+      expect(blame[0].startLineNumber).toBe 1
+      expect(blame[0].linesInHunk).toBe 3
+      expect(blame[0].signature.name).toBe 'Gabriel Isenberg'
+      expect(blame[0].signature.email).toBe 'gisenberg@gmail.com'
+      expect(blame[0].signature.when.time).toBe 1442122439
+      expect(blame[0].signature.when.offset).toBe -420
+
+    it "throws an error if the file doesn't exist", ->
+      expect(-> repo.getBlame('missing.txt')).toThrow()

src/repository.cc

@@ -61,6 +61,7 @@ void Repository::Init(Local<Object> target) {
   Nan::SetMethod(proto, "getReferences", Repository::GetReferences);
   Nan::SetMethod(proto, "checkoutRef", Repository::CheckoutReference);
   Nan::SetMethod(proto, "add", Repository::Add);
+  Nan::SetMethod(proto, "getBlame", Repository::GetBlame);
 
   target->Set(Nan::New<String>("Repository").ToLocalChecked(),
                                 newTemplate->GetFunction());
@@ -910,6 +911,65 @@ NAN_METHOD(Repository::Add) {
   info.GetReturnValue().Set(Nan::New<Boolean>(true));
 }
 
+NAN_METHOD(Repository::GetBlame) {
+  Nan::HandleScope scope;
+
+  git_repository* repository = GetRepository(info);
+  std::string path(*String::Utf8Value(info[0]));
+
+  git_blame_options blameOpts = GIT_BLAME_OPTIONS_INIT;
+  git_blame *blame = NULL;
+
+  if (git_blame_file(&blame, repository, path.c_str(), &blameOpts) != GIT_OK) {
+    const git_error* e = giterr_last();
+    if (e != NULL)
+      return Nan::ThrowError(e->message);
+    else
+      return Nan::ThrowError("Unknown error getting blame.");
+  }
+
+  size_t hunkCount = git_blame_get_hunk_count(blame);
+  Local<Object> v8Ranges = Nan::New<Array>(hunkCount);
+
+  for (size_t i = 0; i < hunkCount; i++) {
+    const git_blame_hunk *hunk = git_blame_get_hunk_byindex(blame, i);
+    const git_signature *finalSig = hunk->final_signature;
+    char commitId[10] = {0};
+    git_oid_tostr(commitId, sizeof(commitId), &hunk->final_commit_id);
+
+    Local<Object> v8Range = Nan::New<Object>();
+    Local<Object> signature = Nan::New<Object>();
+    Local<Object> when = Nan::New<Object>();
+
+    when->Set(Nan::New<String>("time").ToLocalChecked(),
+                  Nan::New<Number>(finalSig->when.time));
+    when->Set(Nan::New<String>("offset").ToLocalChecked(),
+                  Nan::New<Number>(finalSig->when.offset));
+
+    signature->Set(Nan::New<String>("name").ToLocalChecked(),
+                  Nan::New<String>(finalSig->name).ToLocalChecked());
+    signature->Set(Nan::New<String>("email").ToLocalChecked(),
+                  Nan::New<String>(finalSig->email).ToLocalChecked());
+    signature->Set(Nan::New<String>("when").ToLocalChecked(),
+                  when);
+
+    v8Range->Set(Nan::New<String>("commitId").ToLocalChecked(),
+                  Nan::New<String>(commitId).ToLocalChecked());
+    v8Range->Set(Nan::New<String>("startLineNumber").ToLocalChecked(),
+                  Nan::New<Number>(hunk->final_start_line_number));
+    v8Range->Set(Nan::New<String>("linesInHunk").ToLocalChecked(),
+                  Nan::New<Number>(hunk->lines_in_hunk));
+    v8Range->Set(Nan::New<String>("signature").ToLocalChecked(),
+                  signature);
+
+    v8Ranges->Set(i, v8Range);
+  }
+
+  git_blame_free(blame);
+
+  info.GetReturnValue().Set(v8Ranges);
+}
+
 Repository::Repository(Local<String> path) {
   Nan::HandleScope scope;
 

src/repository.h

@@ -59,6 +59,7 @@ class Repository : public Nan::ObjectWrap {
   static NAN_METHOD(GetReferences);
   static NAN_METHOD(CheckoutReference);
   static NAN_METHOD(Add);
+  static NAN_METHOD(GetBlame);
 
   static int StatusCallback(const char *path, unsigned int status,
                             void *payload);