build: add github.com/fsmiamoto/git-todo-parser

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

@@ -0,0 +1,141 @@
+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")
+)
+
+func Parse(f io.Reader) ([]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)
+		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) (Todo, error) {
+	var todo Todo
+
+	if strings.HasPrefix(line, CommentChar) {
+		todo.Command = Comment
+		todo.Comment = strings.TrimLeft(line, CommentChar)
+		return todo, nil
+	}
+
+	fields := strings.Fields(line)
+
+	for i := TodoCommand(Pick); i < Comment; i++ {
+		if isCommand(i, fields[0]) {
+			todo.Command = TodoCommand(i)
+			fields = fields[1:]
+			break
+		}
+	}
+
+	if todo.Command == 0 {
+		// unexpected command
+		return todo, ErrUnexpectedCommand
+	}
+
+	if todo.Command == Break {
+		return todo, nil
+	}
+
+	if todo.Command == Label || todo.Command == Reset {
+		if len(fields) == 0 {
+			return todo, ErrMissingLabel
+		}
+		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" {
+			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" {
+			fields = fields[1:]
+		}
+	}
+
+	if len(fields) == 0 {
+		return todo, ErrMissingCommit
+	}
+
+	todo.Commit = fields[0]
+	fields = fields[1:]
+
+	// Trim # and whitespace
+	todo.Msg = strings.TrimPrefix(strings.Join(fields, " "), 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)
+}