1 files changed, 28 insertions, 0 deletions
diff --git a/src/go/printer/printer_test.go b/src/go/printer/printer_test.go
index cb62b3e4f3..3a8ce60431 100644
--- a/src/go/printer/printer_test.go
+++ b/src/go/printer/printer_test.go
@@ -797,3 +797,31 @@ func f() {
 		t.Fatalf("got %q, want %q", got, want)
 	}
 }
+
+func TestSourcePosNewline(t *testing.T) {
+	// We don't provide a syntax for escaping or unescaping characters in line
+	// directives (see https://go.dev/issue/24183#issuecomment-372449628).
+	// As a result, we cannot write a line directive with the correct path for a
+	// filename containing newlines. We should return an error rather than
+	// silently dropping or mangling it.
+
+	fname := "foo\nbar/bar.go"
+	src := `package bar`
+	fset := token.NewFileSet()
+	f, err := parser.ParseFile(fset, fname, src, parser.ParseComments|parser.AllErrors|parser.SkipObjectResolution)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	cfg := &Config{
+		Mode:     SourcePos, // emit line comments
+		Tabwidth: 8,
+	}
+	var buf bytes.Buffer
+	if err := cfg.Fprint(&buf, fset, f); err == nil {
+		t.Errorf("Fprint did not error for source file path containing newline")
+	}
+	if buf.Len() != 0 {
+		t.Errorf("unexpected Fprint output:\n%s", buf.Bytes())
+	}
+}