2 files changed, 34 insertions, 20 deletions

diff --git a/plumbing/object/commit_walker_file.go b/plumbing/object/commit_walker_path.go
index b73e4ce..6a49fd1 100644
--- a/plumbing/object/commit_walker_file.go
+++ b/plumbing/object/commit_walker_path.go
@@ -8,27 +8,39 @@ import (
 	"gopkg.in/src-d/go-git.v4/plumbing/storer"
 )
 
-type commitFileIter struct {
-	fileName      string
+type commitPathIter struct {
+	pathFilter    func(string) bool
 	sourceIter    CommitIter
 	currentCommit *Commit
 	checkParent   bool
 }
 
-// NewCommitFileIterFromIter returns a commit iterator which performs diffTree between
+// NewCommitPathIterFromIter returns a commit iterator which performs diffTree between
 // successive trees returned from the commit iterator from the argument. The purpose of this is
 // to find the commits that explain how the files that match the path came to be.
 // If checkParent is true then the function double checks if potential parent (next commit in a path)
 // is one of the parents in the tree (it's used by `git log --all`).
-func NewCommitFileIterFromIter(fileName string, commitIter CommitIter, checkParent bool) CommitIter {
-	iterator := new(commitFileIter)
+// pathFilter is a function that takes path of file as argument and returns true if we want it
+func NewCommitPathIterFromIter(pathFilter func(string) bool, commitIter CommitIter, checkParent bool) CommitIter {
+	iterator := new(commitPathIter)
 	iterator.sourceIter = commitIter
-	iterator.fileName = fileName
+	iterator.pathFilter = pathFilter
 	iterator.checkParent = checkParent
 	return iterator
 }
 
-func (c *commitFileIter) Next() (*Commit, error) {
+// this function is kept for compatibilty, can be replaced with NewCommitPathIterFromIter
+func NewCommitFileIterFromIter(fileName string, commitIter CommitIter, checkParent bool) CommitIter {
+	return NewCommitPathIterFromIter(
+		func(path string) bool {
+			return path == fileName
+		},
+		commitIter,
+		checkParent,
+	)
+}
+
+func (c *commitPathIter) Next() (*Commit, error) {
 	if c.currentCommit == nil {
 		var err error
 		c.currentCommit, err = c.sourceIter.Next()
@@ -45,7 +57,7 @@ func (c *commitFileIter) Next() (*Commit, error) {
 	return commit, commitErr
 }
 
-func (c *commitFileIter) getNextFileCommit() (*Commit, error) {
+func (c *commitPathIter) getNextFileCommit() (*Commit, error) {
 	for {
 		// Parent-commit can be nil if the current-commit is the initial commit
 		parentCommit, parentCommitErr := c.sourceIter.Next()
@@ -96,9 +108,9 @@ func (c *commitFileIter) getNextFileCommit() (*Commit, error) {
 	}
 }
 
-func (c *commitFileIter) hasFileChange(changes Changes, parent *Commit) bool {
+func (c *commitPathIter) hasFileChange(changes Changes, parent *Commit) bool {
 	for _, change := range changes {
-		if change.name() != c.fileName {
+		if !c.pathFilter(change.name()) {
 			continue
 		}
 
@@ -125,7 +137,7 @@ func isParentHash(hash plumbing.Hash, commit *Commit) bool {
 	return false
 }
 
-func (c *commitFileIter) ForEach(cb func(*Commit) error) error {
+func (c *commitPathIter) ForEach(cb func(*Commit) error) error {
 	for {
 		commit, nextErr := c.Next()
 		if nextErr == io.EOF {
@@ -144,6 +156,6 @@ func (c *commitFileIter) ForEach(cb func(*Commit) error) error {
 	return nil
 }
 
-func (c *commitFileIter) Close() {
+func (c *commitPathIter) Close() {
 	c.sourceIter.Close()
 }
diff --git a/plumbing/object/object.go b/plumbing/object/object.go
index e960e50..c48a18d 100644
--- a/plumbing/object/object.go
+++ b/plumbing/object/object.go
@@ -138,17 +138,19 @@ func (s *Signature) decodeTimeAndTimeZone(b []byte) {
 		return
 	}
 
-	// Include a dummy year in this time.Parse() call to avoid a bug in Go:
-	// https://github.com/golang/go/issues/19750
-	//
-	// Parsing the timezone with no other details causes the tl.Location() call
-	// below to return time.Local instead of the parsed zone in some cases
-	tl, err := time.Parse("2006 -0700", "1970 "+string(b[tzStart:tzStart+timeZoneLength]))
-	if err != nil {
+	timezone := string(b[tzStart : tzStart+timeZoneLength])
+	tzhours, err1 := strconv.ParseInt(timezone[0:3], 10, 64)
+	tzmins, err2 := strconv.ParseInt(timezone[3:], 10, 64)
+	if err1 != nil || err2 != nil {
 		return
 	}
+	if tzhours < 0 {
+		tzmins *= -1
+	}
+
+	tz := time.FixedZone("", int(tzhours*60*60+tzmins*60))
 
-	s.When = s.When.In(tl.Location())
+	s.When = s.When.In(tz)
 }
 
 func (s *Signature) encodeTimeAndTimeZone(w io.Writer) error {