tools/polymer/css_to_wrapper_test.py

#!/usr/bin/env python3
# Copyright 2022 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import css_to_wrapper
import os
import shutil
import tempfile
import unittest

_HERE_DIR = os.path.dirname(__file__)


class CssToWrapperTest(unittest.TestCase):
  def setUp(self):
    self._out_folder = None
    self.maxDiff = None

  def tearDown(self):
    if self._out_folder:
      shutil.rmtree(self._out_folder)

  def _read_out_file(self, file_name):
    assert self._out_folder
    with open(os.path.join(self._out_folder, file_name), 'r') as f:
      return f.read()

  def _run_test(
    self,
    css_file,
    wrapper_file,
    wrapper_file_expected,
    minify=False,
    use_js=False,
    extra_css_files=[],
  ):
    assert not self._out_folder
    self._out_folder = tempfile.mkdtemp(dir=_HERE_DIR)

    args = [
      '--in_folder',
      os.path.join(_HERE_DIR, 'tests'),
      '--out_folder',
      self._out_folder,
      '--in_files',
      css_file,
    ] + extra_css_files

    if minify:
      args.append('--minify')

    if use_js:
      args.append('--use_js')

    css_to_wrapper.main(args)

    actual_wrapper = self._read_out_file(wrapper_file)
    with open(
      os.path.join(_HERE_DIR, 'tests', wrapper_file_expected), 'r'
    ) as f:
      expected_wrapper = f.read()

    self.assertMultiLineEqual(str(expected_wrapper), str(actual_wrapper))

  def testCssToWrapperStylePolymer(self):
    self._run_test(
      'css_to_wrapper/foo_style.css',
      'css_to_wrapper/foo_style.css.ts',
      'css_to_wrapper/expected/foo_style.css.ts',
    )

  def testCssToWrapperStyleLit(self):
    self._run_test(
      'css_to_wrapper/foo_style_lit_only.css',
      'css_to_wrapper/foo_style_lit_only.css.ts',
      'css_to_wrapper/expected/foo_style_lit_only.css.ts',
    )

  # Test case where a Polymer style file is generated from the equivalent Lit
  # file.
  def testCssToWrapperStyleCopy(self):
    self._run_test(
      'css_to_wrapper/foo_style_copy.css',
      'css_to_wrapper/foo_style_copy.css.ts',
      'css_to_wrapper/expected/foo_style_copy.css.ts',
      # Need to pass the Lit file as well, to satisfy an
      # assertion in css_to_wrapper.py.
      extra_css_files=['css_to_wrapper/foo_style_copy_lit.css'],
    )

  def testCssToWrapperStyleNoIncludes(self):
    self._run_test(
      'css_to_wrapper/foo_no_includes_style.css',
      'css_to_wrapper/foo_no_includes_style.css.ts',
      'css_to_wrapper/expected/foo_no_includes_style.css.ts',
    )

  def testCssToWrapperVarsPolymer(self):
    self._run_test(
      'css_to_wrapper/foo_vars.css',
      'css_to_wrapper/foo_vars.css.ts',
      'css_to_wrapper/expected/foo_vars.css.ts',
    )

  def testCssToWrapperVarsLit(self):
    self._run_test(
      'css_to_wrapper/foo_vars_lit_only.css',
      'css_to_wrapper/foo_vars_lit_only.css.ts',
      'css_to_wrapper/expected/foo_vars.css.ts',
    )

  def testCssToWrapperMinify(self):
    self._run_test(
      'css_to_wrapper/css_features.css',
      'css_to_wrapper/css_features.css.ts',
      'css_to_wrapper/expected/css_features.min.css.ts',
      minify=True,
    )

  # Test case where a Polymer style file is generated from the equivalent Lit
  # file and minification is turned on.
  def testCssToWrapperCopyMinify(self):
    self._run_test(
      'css_to_wrapper/css_features_copy.css',
      'css_to_wrapper/css_features_copy.css.ts',
      'css_to_wrapper/expected/css_features_copy.min.css.ts',
      minify=True,
      # Need to pass the Lit file as well, to satisfy an
      # assertion in css_to_wrapper.py.
      extra_css_files=['css_to_wrapper/css_features_copy_lit.css'],
    )

  def testCssToWrapperUseJs(self):
    self._run_test(
      'css_to_wrapper/foo_style.css',
      'css_to_wrapper/foo_style.css.js',
      'css_to_wrapper/expected/foo_style.css.ts',
      use_js=True,
    )

  def testCssToWrapperSchemeRelative(self):
    self._run_test(
      'css_to_wrapper/foo_relative_style.css',
      'css_to_wrapper/foo_relative_style.css.ts',
      'css_to_wrapper/expected/foo_relative_style.css.ts',
    )


if __name__ == '__main__':
  unittest.main()