Switch to porcelain v2

Drop regex-based parsing in favor of
bufio.Scanner based approach

This needs at least git v2.13.2

README.md

@@ -1,25 +1,28 @@
 porcelain
 ============
 
-Parses `git status --porcelain` and outputs nicely formatted strings.
+Parses `git status --porcelain=v2 --branch` and outputs nicely formatted strings for your shell.
 
-**Formatted output with `porcelain -fmt`**
+<img width="646" alt="screen_shot" src="https://user-images.githubusercontent.com/3930615/27802035-9c1b92d2-6021-11e7-9289-7b8a17164bf4.png">
 
-![formatted output screenshot](http://i.imgur.com/d3Ckvbj.png)
+The minimum git version for porcelain v2 with `--branch` is `v2.13.2`.
+Otherwise you can use the old porcelain v1 based parser on the [`legacy` branch](/~https://github.com/robertgzr/porcelain/tree/legacy).
 
-![formatted output screenshot 2](http://i.imgur.com/xAnGH7C.png)
+With a working Go environment do: `go get -u github.com/robertgzr/porcelain`
 
-**Basic output with `porcelain -basic`**
+Binaries can be found [here](/~https://github.com/robertgzr/porcelain/releases).
 
-![basic output screenshot](http://i.imgur.com/F1DnTOA.png)
+## Output explained:
 
-```
-   commit,branch,tracked_branch,ahead,behind,untracked,added,modified,deleted,renamed,copied
-```
+ ` <branch>@<commit> [↑/↓ <ahead/behind count>][untracked][unmerged][modified][dirty/clean]`
 
-With a working Go environment do: `go get -u github.com/robertgzr/porcelain`
+- `?`  : untracked files
+- `‼`  : unmerged : merge in process
+- `Δ`  : modified : unstaged changes
 
-Binaries can be found [here](/~https://github.com/robertgzr/porcelain/releases).
+Definitions taken from: https://www.kernel.org/pub/software/scm/git/docs/gitglossary.html#def_dirty
+- `✘`  : dirty : working tree contains uncommited but staged changes
+- `✔`  : clean : working tree corresponds to the revision referenced by HEAD
 
 ---
 

git.go

@@ -0,0 +1,40 @@
+package main
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"os/exec"
+	"strings"
+)
+
+const notRepoStatus string = "exit status 128"
+
+var ErrNotAGitRepo error = errors.New("not a git repo")
+
+func GetGitOutput(cwd string) (io.Reader, error) {
+	var buf = new(bytes.Buffer)
+
+	cmd := exec.Command("git", "status", "--porcelain=v2", "--branch")
+	cmd.Stderr = buf
+	cmd.Stdout = buf
+
+	if err := cmd.Run(); err != nil {
+		if cmd.ProcessState.String() == notRepoStatus {
+			return nil, ErrNotAGitRepo
+		}
+		return nil, err
+	}
+
+	return buf, nil
+}
+
+func PathToGitDir(cwd string) (string, error) {
+	cmd := exec.Command("git", "rev-parse", "--absolute-git-dir")
+	cmd.Dir = cwd
+	out, err := cmd.Output()
+	if err != nil {
+		return "", err
+	}
+	return strings.TrimSpace(string(out)), nil
+}

parse.go

@@ -0,0 +1,154 @@
+package main
+
+import (
+	"bufio"
+	"io"
+	"strconv"
+	"strings"
+)
+
+func consumeNext(s *bufio.Scanner) string {
+	if s.Scan() {
+		return s.Text()
+	}
+	return ""
+}
+
+func (pi *PorcInfo) ParsePorcInfo(r io.Reader) error {
+	var err error
+	var s = bufio.NewScanner(r)
+
+	for s.Scan() {
+		if len(s.Text()) < 1 {
+			continue
+		}
+
+		pi.ParseLine(s.Text())
+	}
+
+	return err
+}
+
+func (pi *PorcInfo) ParseLine(line string) error {
+	s := bufio.NewScanner(strings.NewReader(line))
+	// switch to a word based scanner
+	s.Split(bufio.ScanWords)
+
+	for s.Scan() {
+		switch s.Text() {
+		case "#":
+			pi.parseBranchInfo(s)
+		case "1":
+			pi.parseTrackedFile(s)
+		case "2":
+			pi.parseRenamedFile(s)
+		case "u":
+			pi.unmerged++
+		case "?":
+			pi.untracked++
+		}
+	}
+	return nil
+}
+
+func (pi *PorcInfo) parseBranchInfo(s *bufio.Scanner) (err error) {
+	// uses the word based scanner from ParseLine
+	for s.Scan() {
+		switch s.Text() {
+		case "branch.oid":
+			pi.commit = consumeNext(s)
+		case "branch.head":
+			pi.branch = consumeNext(s)
+		case "branch.upstream":
+			pi.upstream = consumeNext(s)
+		case "branch.ab":
+			err = pi.parseAheadBehind(s)
+		}
+	}
+	return err
+}
+
+func (pi *PorcInfo) parseAheadBehind(s *bufio.Scanner) error {
+	// uses the word based scanner from ParseLine
+	for s.Scan() {
+		i, err := strconv.Atoi(s.Text()[1:])
+		if err != nil {
+			return err
+		}
+
+		switch s.Text()[:1] {
+		case "+":
+			pi.ahead = i
+		case "-":
+			pi.behind = i
+		}
+	}
+	return nil
+}
+
+// parseTrackedFile parses the porcelain v2 output for tracked entries
+// doc: https://git-scm.com/docs/git-status#_changed_tracked_entries
+//
+func (pi *PorcInfo) parseTrackedFile(s *bufio.Scanner) error {
+	// uses the word based scanner from ParseLine
+	var index int
+	for s.Scan() {
+		switch index {
+		case 0: // xy
+			pi.parseXY(s.Text())
+		default:
+			continue
+			// case 1: // sub
+			// 	if s.Text() != "N..." {
+			// 		log.Println("is submodule!!!")
+			// 	}
+			// case 2: // mH - octal file mode in HEAD
+			// 	log.Println(index, s.Text())
+			// case 3: // mI - octal file mode in index
+			// 	log.Println(index, s.Text())
+			// case 4: // mW - octal file mode in worktree
+			// 	log.Println(index, s.Text())
+			// case 5: // hH - object name in HEAD
+			// 	log.Println(index, s.Text())
+			// case 6: // hI - object name in index
+			// 	log.Println(index, s.Text())
+			// case 7: // path
+			// 	log.Println(index, s.Text())
+		}
+		index++
+	}
+	return nil
+}
+
+func (pi *PorcInfo) parseXY(xy string) error {
+	switch xy[:1] { // parse staged
+	case "M":
+		pi.Staged.modified++
+	case "A":
+		pi.Staged.added++
+	case "D":
+		pi.Staged.deleted++
+	case "R":
+		pi.Staged.renamed++
+	case "C":
+		pi.Staged.copied++
+	}
+
+	switch xy[1:] { // parse unstaged
+	case "M":
+		pi.Unstaged.modified++
+	case "A":
+		pi.Unstaged.added++
+	case "D":
+		pi.Unstaged.deleted++
+	case "R":
+		pi.Unstaged.renamed++
+	case "C":
+		pi.Unstaged.copied++
+	}
+	return nil
+}
+
+func (pi *PorcInfo) parseRenamedFile(s *bufio.Scanner) error {
+	return pi.parseTrackedFile(s)
+}

parse_test.go

@@ -0,0 +1,61 @@
+package main
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+)
+
+const gitoutput string = `
+# branch.oid 51c9c58e2175b768137c1e38865f394c76a7d49d
+# branch.head master
+# branch.upstream origin/master
+# branch.ab +1 -10
+1 .M N... 100644 100644 100644 3e2ceb914cf9be46bf235432781840f4145363fd 3e2ceb914cf9be46bf235432781840f4145363fd Gopkg.lock
+1 .M N... 100644 100644 100644 cecb683e6e626bcba909ddd36d3357d49f0cfd09 cecb683e6e626bcba909ddd36d3357d49f0cfd09 Gopkg.toml
+1 .M N... 100644 100644 100644 aea984b7df090ce3a5826a854f3e5364cd8f2ccd aea984b7df090ce3a5826a854f3e5364cd8f2ccd porcelain.go
+1 .D N... 100644 100644 000000 6d9532ba55b84ec4faf214f9cdb9ce70ec8f4f5b 6d9532ba55b84ec4faf214f9cdb9ce70ec8f4f5b porcelain_test.go
+2 R. N... 100644 100644 100644 44d0a25072ee3706a8015bef72bdd2c4ab6da76d 44d0a25072ee3706a8015bef72bdd2c4ab6da76d R100 hm.rb     hw.rb
+u UU N... 100644 100644 100644 100644 ac51efdc3df4f4fd328d1a02ad05331d8e2c9111 36c06c8752c78d2aff89571132f3bf7841a7b5c3 e85207e04dfdd5eb0a1e9febbc67fd837c44a1cd hw.rb
+? _porcelain_test.go
+? git.go
+? git_test.go
+? goreleaser.yml
+? vendor/
+`
+
+var expectedPorcInfo = PorcInfo{
+	branch:    "master",
+	commit:    "51c9c58e2175b768137c1e38865f394c76a7d49d",
+	remote:    "",
+	upstream:  "origin/master",
+	ahead:     1,
+	behind:    10,
+	untracked: 5,
+	unmerged:  1,
+	Unstaged: GitArea{
+		modified: 3,
+		added:    0,
+		deleted:  1,
+		renamed:  0,
+		copied:   0,
+	},
+	Staged: GitArea{
+		modified: 0,
+		added:    0,
+		deleted:  0,
+		renamed:  1,
+		copied:   0,
+	},
+}
+
+func TestParsePorcInfo(t *testing.T) {
+	var pi = new(PorcInfo)
+	if err := pi.ParsePorcInfo(strings.NewReader(gitoutput)); err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(&expectedPorcInfo, pi) {
+		t.Logf("%#+v\n", pi)
+		t.FailNow()
+	}
+}