improved git commit object parsing - missing timezone parsing for aut…

…hored and committed time

internal/mygit/mygit.go

@@ -45,12 +45,12 @@ func Log() error {
 	}
 	limit := 3
 	count := 0
-	for c, err := objects.ReadCommit(commitSha); c != nil && err == nil && len(c.Parents) > 0; c, err = objects.ReadCommit(c.Parents[0]) {
+	for c, err := objects.ReadCommit(commitSha); c != nil && err == nil; c, err = objects.ReadCommit(c.Parents[0]) {
 		fmt.Println(c)
-		count++
-		if count >= limit {
+		if count >= limit || len(c.Parents) == 0 {
 			break
 		}
+		count++
 	}
 
 	return nil

internal/mygit/objects/object.go

@@ -19,14 +19,16 @@ type (
 	}
 	objectType int
 	Commit     struct {
-		Sha           []byte
-		Tree          []byte
-		Parents       [][]byte
-		Author        string
-		AuthoredTime  time.Time
-		Committer     string
-		CommittedTime time.Time
-		Message       []byte
+		Sha            []byte
+		Tree           []byte
+		Parents        [][]byte
+		Author         string
+		AuthorEmail    string
+		AuthoredTime   time.Time
+		Committer      string
+		CommitterEmail string
+		CommittedTime  time.Time
+		Message        []byte
 	}
 	Tree struct {
 		Sha   []byte
@@ -49,9 +51,12 @@ const (
 )
 
 func (c Commit) String() string {
+	fmt.Printf("commit: %s\n", string(c.Sha))
 	fmt.Printf("tree: %s\n", string(c.Tree))
 	for _, v := range c.Parents {
 		fmt.Printf("parent: %s\n", string(v))
 	}
+	fmt.Printf("%s <%s> %s\n", c.Author, c.AuthorEmail, c.AuthoredTime.String())
+	fmt.Printf("%s <%s> %s\n", c.Committer, c.CommitterEmail, c.CommittedTime.String())
 	return fmt.Sprintf("message: \n%s\n", c.Message)
 }

internal/mygit/objects/reader.go

@@ -13,6 +13,7 @@ import (
 	"os"
 	"path/filepath"
 	"strconv"
+	"time"
 )
 
 // FlattenTree turns a TreeObject structure into a flat list of file paths
@@ -202,38 +203,84 @@ func readCommit(obj *Object) (*Commit, error) {
 	c := &Commit{Sha: obj.Sha}
 
 	s := bufio.NewScanner(r)
-	var parts [][]byte
-	parts = lineParts(s)
-	c.Tree = parts[1]
-	for {
-		parts = lineParts(s)
-		if string(parts[0]) == "parent" {
-			c.Parents = append(c.Parents, parts[1])
-		} else {
-			break
-		}
-	}
-	if string(parts[0]) != "author" {
-		return nil, fmt.Errorf("expected author got %s", string(parts[0]))
-	}
-	parts = lineParts(s)
-	if string(parts[0]) != "committer" {
-		return nil, fmt.Errorf("expected committer got %s", string(parts[0]))
-	}
-	s.Scan()
-	if s.Text() != "" {
-		return nil, fmt.Errorf("expected newline got %s", s.Text())
-	}
+
 	for {
 		if !s.Scan() {
 			break
 		}
-		c.Message = append(c.Message, s.Bytes()...)
+		l := s.Bytes()
+		p := bytes.SplitN(l, []byte(" "), 2)
+		t := string(p[0])
+		if c.Tree == nil {
+			if t != "tree" {
+				return nil, fmt.Errorf("expected tree got %s", t)
+			}
+			c.Tree = p[1]
+			continue
+		}
+		// can be parent
+		if t == "parent" {
+			c.Parents = append(c.Parents, p[1])
+			continue
+		}
+		if c.Author == "" {
+			// should be author
+			if t != "author" {
+				return nil, fmt.Errorf("expected author got %s", t)
+			}
+			// decode author line
+			if err := readAuthor(p[1], c); err != nil {
+				return nil, err
+			}
+			continue
+		}
+		if c.Committer == "" {
+			// should be committer
+			if t != "committer" {
+				return nil, fmt.Errorf("expected committer got %s", t)
+			}
+			// decode committer line
+			if err := readCommitter(p[1], c); err != nil {
+				return nil, err
+			}
+			continue
+		}
+		// can be GPG Signature
+		if t == "gpgsig" {
+			// currently not implementing @todo implement signed commits
+			continue
+		}
+		// now we have the message body hopefully
+		c.Message = append(c.Message, l...)
 	}
 
 	return c, nil
 }
-func lineParts(s *bufio.Scanner) [][]byte {
-	s.Scan()
-	return bytes.Split(s.Bytes(), []byte(" "))
+
+func readAuthor(b []byte, c *Commit) error {
+	s := bytes.Index(b, []byte("<"))
+	e := bytes.Index(b, []byte(">"))
+	c.Author = string(b[0 : s-1])
+	c.AuthorEmail = string(b[s+1 : e])
+	ut, err := strconv.ParseInt(string(b[e+2:e+2+10]), 10, 64)
+	if err != nil {
+		return err
+	}
+	// @todo timezone part
+	c.AuthoredTime = time.Unix(ut, 0)
+	return nil
+}
+
+func readCommitter(b []byte, c *Commit) error {
+	s := bytes.Index(b, []byte("<"))
+	e := bytes.Index(b, []byte(">"))
+	c.Committer = string(b[0 : s-1])
+	c.CommitterEmail = string(b[s+1 : e])
+	ut, err := strconv.ParseInt(string(b[e+2:e+2+10]), 10, 64)
+	if err != nil {
+		return err
+	}
+	// @todo timezone part
+	c.CommittedTime = time.Unix(ut, 0)
+	return nil
 }