# Copyright 2019 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""Tests for code_template."""

import string
import unittest
from compiler.back_end.util import code_template

def _format_template_str(template: str, **kwargs) -> str:
  return code_template.format_template(string.Template(template), **kwargs)

class FormatTest(unittest.TestCase):
  """Tests for code_template.format."""

  def test_no_replacement_fields(self):
    self.assertEqual("foo", _format_template_str("foo"))
    self.assertEqual("{foo}", _format_template_str("{foo}"))
    self.assertEqual("${foo}", _format_template_str("$${foo}"))

  def test_one_replacement_field(self):
    self.assertEqual("foo", _format_template_str("${bar}", bar="foo"))
    self.assertEqual("bazfoo",
                     _format_template_str("baz${bar}", bar="foo"))
    self.assertEqual("foobaz",
                     _format_template_str("${bar}baz", bar="foo"))
    self.assertEqual("bazfooqux",
                     _format_template_str("baz${bar}qux", bar="foo"))

  def test_one_replacement_field_with_formatting(self):
    # Basic string.Templates don't support formatting values.
    self.assertRaises(ValueError,
                     _format_template_str, "${bar:.6f}", bar=1)

  def test_one_replacement_field_value_missing(self):
    self.assertRaises(KeyError, _format_template_str, "${bar}")

  def test_multiple_replacement_fields(self):
    self.assertEqual(" aaa  bbb   ",
                     _format_template_str(" ${bar}  ${baz}   ",
                                                   bar="aaa",
                                                   baz="bbb"))


class ParseTemplatesTest(unittest.TestCase):
  """Tests for code_template.parse_templates."""

  def assertTemplatesEqual(self, expected, actual): # pylint:disable=invalid-name
    """Compares the results of a parse_templates"""
    # Extract the name and template from the result tuple
    actual = {
        k: v.template for k, v in actual._asdict().items()
    }
    self.assertEqual(expected, actual)

  def test_handles_no_template_case(self):
    self.assertTemplatesEqual({}, code_template.parse_templates(""))
    self.assertTemplatesEqual({}, code_template.parse_templates(
        "this is not a template"))

  def test_handles_one_template_at_start(self):
    self.assertTemplatesEqual({"foo": "bar"},
                     code_template.parse_templates("** foo **\nbar"))

  def test_handles_one_template_after_start(self):
    self.assertTemplatesEqual(
        {"foo": "bar"},
        code_template.parse_templates("text\n** foo **\nbar"))

  def test_handles_delimiter_with_other_text(self):
    self.assertTemplatesEqual(
        {"foo": "bar"},
        code_template.parse_templates("text\n// ** foo ** ////\nbar"))
    self.assertTemplatesEqual(
        {"foo": "bar"},
        code_template.parse_templates("text\n# ** foo ** #####\nbar"))

  def test_handles_multiple_delimiters(self):
    self.assertTemplatesEqual({"foo": "bar",
                      "baz": "qux"}, code_template.parse_templates(
                          "** foo **\nbar\n** baz **\nqux"))

  def test_returns_object_with_attributes(self):
    self.assertEqual("bar", code_template.parse_templates(
        "** foo **\nbar\n** baz **\nqux").foo.template)

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