608e53be

feat(scanner): detect untagged @claude markers in Go comments

a73x   2026-04-29 05:42

---

diff --git a/internal/scanner/scanner.go b/internal/scanner/scanner.go
new file mode 100644
index 0000000..dc41796
--- /dev/null
+++ b/internal/scanner/scanner.go
@@ -0,0 +1,60 @@
package scanner

import (
	"bufio"
	"os"
	"path/filepath"
	"regexp"
	"strings"
)

type Marker struct {
	Line   int
	Text   string
	Tagged bool
	UUID   string
}

// commentPrefixes maps file extension (lowercase, with dot) to the line-comment prefix.
var commentPrefixes = map[string]string{
	".go": "//",
}

var (
	untaggedRE = regexp.MustCompile(`^@claude\s+\S`)
	taggedRE   = regexp.MustCompile(`^@claude\[(fw-[0-9a-f]{8})\]\s+\S`)
)

func Scan(path string) ([]Marker, error) {
	ext := strings.ToLower(filepath.Ext(path))
	prefix, ok := commentPrefixes[ext]
	if !ok {
		return nil, nil
	}
	f, err := os.Open(path)
	if err != nil {
		return nil, err
	}
	defer f.Close()

	var markers []Marker
	sc := bufio.NewScanner(f)
	sc.Buffer(make([]byte, 1024*1024), 1024*1024)
	line := 0
	for sc.Scan() {
		line++
		raw := strings.TrimSpace(sc.Text())
		if !strings.HasPrefix(raw, prefix) {
			continue
		}
		body := strings.TrimSpace(strings.TrimPrefix(raw, prefix))
		if m := taggedRE.FindStringSubmatch(body); m != nil {
			markers = append(markers, Marker{Line: line, Text: body, Tagged: true, UUID: m[1]})
			continue
		}
		if untaggedRE.MatchString(body) {
			markers = append(markers, Marker{Line: line, Text: body})
		}
	}
	return markers, sc.Err()
}
diff --git a/internal/scanner/scanner_test.go b/internal/scanner/scanner_test.go
new file mode 100644
index 0000000..a097963
--- /dev/null
+++ b/internal/scanner/scanner_test.go
@@ -0,0 +1,39 @@
package scanner

import (
	"os"
	"path/filepath"
	"testing"
)

func writeFile(t *testing.T, dir, name, content string) string {
	t.Helper()
	path := filepath.Join(dir, name)
	if err := os.WriteFile(path, []byte(content), 0o644); err != nil {
		t.Fatal(err)
	}
	return path
}

func TestScanGoFileSingleUntaggedMarker(t *testing.T) {
	dir := t.TempDir()
	path := writeFile(t, dir, "foo.go", "package foo\n\n// @claude write a test for foo\nfunc Foo() {}\n")

	markers, err := Scan(path)
	if err != nil {
		t.Fatalf("Scan: %v", err)
	}
	if len(markers) != 1 {
		t.Fatalf("got %d markers, want 1: %#v", len(markers), markers)
	}
	m := markers[0]
	if m.Line != 3 {
		t.Errorf("Line = %d, want 3", m.Line)
	}
	if m.Text != "@claude write a test for foo" {
		t.Errorf("Text = %q, want %q", m.Text, "@claude write a test for foo")
	}
	if m.Tagged {
		t.Errorf("Tagged = true, want false")
	}
}