fix(test): strip colour codes before looking for the lint skip notice (CI run 8937)

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

test/lintgate/lintgate_test.go

@@ -10,6 +10,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"strings"
 	"testing"
 )
@@ -40,10 +41,13 @@ func scratchModule(t *testing.T) string {
 	return dir
 }
 
+// ansi matches the colour escape sequences task prints when it thinks it has a terminal.
+var ansi = regexp.MustCompile("\x1b\\[[0-9;]*m")
+
 // hasSkipNotice reports whether the skip notice was printed as output. Task echoes the command
 // line first, and that line contains the same words, so a substring match would be vacuous.
 func hasSkipNotice(out string) bool {
-	for _, line := range strings.Split(out, "\n") {
+	for _, line := range strings.Split(ansi.ReplaceAllString(out, ""), "\n") {
 		if strings.HasPrefix(line, "golangci-lint not installed") {
 			return true
 		}
@@ -125,3 +129,15 @@ func TestTaskLint_SkipsWithANoticeWhenGolangciLintIsAbsent(t *testing.T) {
 		t.Fatalf("expected the skip notice; output:\n%s", out)
 	}
 }
+
+// CI runs task with colour on, so the notice line starts with an escape sequence; a bare
+// prefix match missed it there while passing on a terminal-less local run.
+func TestHasSkipNotice_SeesTheNoticeBehindColourCodes(t *testing.T) {
+	out := "\x1b[32mtask: [lint] ...\n\x1b[0mgolangci-lint not installed — skipping (CI installs it)\n"
+	if !hasSkipNotice(out) {
+		t.Fatalf("notice not found in coloured output: %q", out)
+	}
+	if hasSkipNotice("\x1b[32mtask: [lint] if command -v golangci-lint ...; echo \"golangci-lint not installed\"\n") {
+		t.Fatal("the echoed command line must not count as the notice")
+	}
+}