feat(config): preserve lint/tool directives by default across supported languages

internal/processor/engine_test.go

@@ -115,3 +115,45 @@ func TestStripComments(t *testing.T) {
 		})
 	}
 }
+
+func TestStripCommentsPreservesDirectives(t *testing.T) {
+	def := config.Default()
+	cases := []struct {
+		name string
+		file string
+		src  string
+	}{
+		{"go nolint", "a.go", "x := 1 //nolint:errcheck\n"},
+		{"go build directive", "a.go", "//go:build linux\npackage main\n"},
+		{"python noqa", "a.py", "x = 1  # noqa: E501\n"},
+		{"python type ignore", "a.py", "y = 2  # type: ignore\n"},
+		{"python nosec", "a.py", "p = 1  # nosec B105\n"},
+		{"js eslint disable", "a.js", "const a = 1 // eslint-disable-line\n"},
+		{"ts expect error", "a.ts", "const b = 1 // @ts-expect-error\n"},
+		{"c clang nolint", "a.c", "int x; // NOLINT(cert-err58-cpp)\n"},
+		{"shell shellcheck", "a.sh", "y=1 # shellcheck disable=SC2086\n"},
+		{"ruby rubocop", "a.rb", "x = 1 # rubocop:disable Style/Foo\n"},
+		{"ruby frozen string", "a.rb", "# frozen_string_literal: true\nx = 1\n"},
+		{"haskell pragma", "a.hs", "{-# LANGUAGE OverloadedStrings #-}\nmodule M where\n"},
+		{"php phpstan", "a.php", "<?php\n$x = 1; // @phpstan-ignore-line\n"},
+		{"lua luacheck", "a.lua", "local x = 1 -- luacheck: ignore\n"},
+		{"java nopmd", "a.java", "int x = 1; // NOPMD\n"},
+		{"csharp resharper", "a.cs", "int x = 1; // ReSharper disable once Foo\n"},
+		{"dart ignore for file", "a.dart", "// ignore_for_file: foo\nvar x = 1;\n"},
+		{"elixir credo", "a.ex", "x = 1 # credo:disable-for-next-line\n"},
+		{"solidity solhint", "a.sol", "uint x; // solhint-disable-next-line\n"},
+		{"kotlin ktlint", "a.kt", "val x = 1 // ktlint-disable\n"},
+		{"yaml yamllint", "a.yml", "x: 1 # yamllint disable-line\n"},
+	}
+	for _, c := range cases {
+		t.Run(c.name, func(t *testing.T) {
+			out, _, err := StripComments([]byte(c.src), c.file, def, Options{})
+			if err != nil {
+				t.Fatalf("err: %v", err)
+			}
+			if string(out) != c.src {
+				t.Errorf("directive not preserved:\ngot  %q\nwant %q", out, c.src)
+			}
+		})
+	}
+}