Switch git-todo-parser from fsmiamoto original repo to stefanhaller's fork

Sometimes it takes a while to get PRs accepted upstream, and this blocks our
progress. Since I'm pretty much the only one making changes there anyway, it
makes sense to point to my fork directly.

vendor/github.com/stefanhaller/git-todo-parser/todo/parse.go

@@ -0,0 +1,158 @@
+package todo
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+)
+
+var (
+	ErrUnexpectedCommand = errors.New("unexpected command")
+	ErrMissingLabel      = errors.New("missing label")
+	ErrMissingCommit     = errors.New("missing commit")
+	ErrMissingExecCmd    = errors.New("missing command for exec")
+	ErrMissingRef        = errors.New("missing ref")
+)
+
+func Parse(f io.Reader, commentChar byte) ([]Todo, error) {
+	var result []Todo
+
+	scanner := bufio.NewScanner(f)
+	scanner.Split(bufio.ScanLines)
+
+	for scanner.Scan() {
+		line := scanner.Text()
+
+		trimmed := strings.TrimSpace(line)
+		if trimmed == "" {
+			continue
+		}
+
+		cmd, err := parseLine(line, commentChar)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse line %q: %w", line, err)
+		}
+
+		result = append(result, cmd)
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("failed to parse input: %w", err)
+	}
+
+	return result, nil
+}
+
+func parseLine(line string, commentChar byte) (Todo, error) {
+	var todo Todo
+
+	if line[0] == commentChar {
+		todo.Command = Comment
+		todo.Comment = line[1:]
+		return todo, nil
+	}
+
+	fields := strings.Fields(line)
+
+	var commandLen int
+	for i := Pick; i < Comment; i++ {
+		if isCommand(i, fields[0]) {
+			todo.Command = i
+			commandLen = len(fields[0])
+			fields = fields[1:]
+			break
+		}
+	}
+
+	if todo.Command == 0 {
+		// unexpected command
+		return todo, ErrUnexpectedCommand
+	}
+
+	if todo.Command == Break || todo.Command == NoOp {
+		return todo, nil
+	}
+
+	if todo.Command == Label || todo.Command == Reset {
+		restOfLine := strings.TrimSpace(line[commandLen:])
+		if todo.Command == Reset && restOfLine == "[new root]" {
+			todo.Label = restOfLine
+		} else if len(fields) == 0 {
+			return todo, ErrMissingLabel
+		} else {
+			todo.Label = fields[0]
+		}
+		return todo, nil
+	}
+
+	if todo.Command == Exec {
+		if len(fields) == 0 {
+			return todo, ErrMissingExecCmd
+		}
+		todo.ExecCommand = strings.Join(fields, " ")
+		return todo, nil
+	}
+
+	if todo.Command == Merge {
+		if fields[0] == "-C" || fields[0] == "-c" {
+			todo.Flag = fields[0]
+			fields = fields[1:]
+			if len(fields) == 0 {
+				return todo, ErrMissingCommit
+			}
+			todo.Commit = fields[0]
+			fields = fields[1:]
+		}
+		if len(fields) == 0 {
+			return todo, ErrMissingLabel
+		}
+		todo.Label = fields[0]
+		fields = fields[1:]
+		if fields[0] == "#" {
+			fields = fields[1:]
+			todo.Msg = strings.Join(fields, " ")
+		}
+		return todo, nil
+	}
+
+	if todo.Command == Fixup {
+		if len(fields) == 0 {
+			return todo, ErrMissingCommit
+		}
+		// Skip flags
+		if fields[0] == "-C" || fields[0] == "-c" {
+			todo.Flag = fields[0]
+			fields = fields[1:]
+		}
+	}
+
+	if todo.Command == UpdateRef {
+		if len(fields) == 0 {
+			return todo, ErrMissingRef
+		}
+		todo.Ref = fields[0]
+		return todo, nil
+	}
+
+	if len(fields) == 0 {
+		return todo, ErrMissingCommit
+	}
+
+	todo.Commit = fields[0]
+	fields = fields[1:]
+
+	// Trim comment char and whitespace
+	todo.Msg = strings.TrimPrefix(strings.Join(fields, " "), fmt.Sprintf("%c ", commentChar))
+
+	return todo, nil
+}
+
+func isCommand(i TodoCommand, s string) bool {
+	if i < 0 || i > Comment {
+		return false
+	}
+	return len(s) > 0 &&
+		(todoCommandInfo[i].cmd == s || todoCommandInfo[i].nickname == s)
+}