# 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 parser."""
import unittest
from compiler.front_end import lr1
from compiler.front_end import parser
from compiler.front_end import tokenizer
from compiler.util import parser_types
# TODO(bolms): This is repeated in lr1_test.py; separate into test utils?
def _parse_productions(*productions):
"""Parses text into a grammar by calling Production.parse on each line."""
return [parser_types.Production.parse(p) for p in productions]
_EXAMPLE_DIVIDER = "\n" + "=" * 80 + "\n"
_MESSAGE_ERROR_DIVIDER = "\n" + "-" * 80 + "\n"
_ERROR_DIVIDER = "\n---\n"
class ParserGeneratorTest(unittest.TestCase):
"""Tests parser.parse_error_examples and generate_parser."""
def test_parse_good_error_examples(self):
errors = parser.parse_error_examples(
_EXAMPLE_DIVIDER + # ======...
"structure names must be Camel" + # Message.
_MESSAGE_ERROR_DIVIDER + # ------...
"struct $ERR FOO" + # First example.
_ERROR_DIVIDER + # ---
"struct $ERR foo" + # Second example.
_EXAMPLE_DIVIDER + # ======...
' \n struct must be followed by ":" \n\n' + # Second message.
_MESSAGE_ERROR_DIVIDER + # ------...
"struct Foo $ERR") # Example for second message.
self.assertEqual(tokenizer.tokenize("struct FOO", "")[0], errors[0][0])
self.assertEqual("structure names must be Camel", errors[0][2])
self.assertEqual(tokenizer.tokenize("struct foo", "")[0], errors[1][0])
self.assertEqual("structure names must be Camel", errors[1][2])
self.assertEqual(tokenizer.tokenize("struct Foo ", "")[0], errors[2][0])
self.assertEqual('struct must be followed by ":"', errors[2][2])
def test_parse_good_wildcard_example(self):
errors = parser.parse_error_examples(
_EXAMPLE_DIVIDER + # ======...
' \n struct must be followed by ":" \n\n' + # Second message.
_MESSAGE_ERROR_DIVIDER + # ------...
"struct Foo $ERR $ANY")
tokens = tokenizer.tokenize("struct Foo ", "")[0]
# The $ANY token should come just before the end-of-line token in the parsed
# result.
tokens.insert(-1, lr1.ANY_TOKEN)
self.assertEqual(tokens, errors[0][0])
self.assertEqual('struct must be followed by ":"', errors[0][2])
def test_parse_with_no_error_marker(self):
self.assertRaises(
parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg" + _MESSAGE_ERROR_DIVIDER + "-- doc")
def test_that_no_error_example_fails(self):
self.assertRaises(parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg" + _EXAMPLE_DIVIDER + "msg" +
_MESSAGE_ERROR_DIVIDER + "example")
def test_that_message_example_divider_must_be_on_its_own_line(self):
self.assertRaises(parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg" + "-" * 80 + "example")
self.assertRaises(parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg\n" + "-" * 80 + "example")
self.assertRaises(parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg" + "-" * 80 + "\nexample")
self.assertRaises(parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg\n" + "-" * 80 + " \nexample")
def test_that_example_divider_must_be_on_its_own_line(self):
self.assertRaises(
parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg" + _MESSAGE_ERROR_DIVIDER + "example" + "=" * 80
+ "msg" + _MESSAGE_ERROR_DIVIDER + "example")
self.assertRaises(
parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg" + _MESSAGE_ERROR_DIVIDER + "example\n" + "=" *
80 + "msg" + _MESSAGE_ERROR_DIVIDER + "example")
self.assertRaises(
parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg" + _MESSAGE_ERROR_DIVIDER + "example" + "=" * 80
+ "\nmsg" + _MESSAGE_ERROR_DIVIDER + "example")
self.assertRaises(
parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "msg" + _MESSAGE_ERROR_DIVIDER + "example\n" + "=" *
80 + " \nmsg" + _MESSAGE_ERROR_DIVIDER + "example")
def test_that_tokenization_failure_results_in_failure(self):
self.assertRaises(
parser.ParserGenerationError,
parser.parse_error_examples,
_EXAMPLE_DIVIDER + "message" + _MESSAGE_ERROR_DIVIDER + "|")
def test_generate_parser(self):
self.assertTrue(parser.generate_parser("C", _parse_productions("C -> s"),
[]))
self.assertTrue(parser.generate_parser(
"C", _parse_productions("C -> s", "C -> d"), []))
def test_generated_parser_error(self):
test_parser = parser.generate_parser(
"C", _parse_productions("C -> s", "C -> d"),
[([parser_types.Token("s", "s", None),
parser_types.Token("s", "s", None)],
parser_types.Token("s", "s", None),
"double s", "ss")])
parse_result = test_parser.parse([parser_types.Token("s", "s", None),
parser_types.Token("s", "s", None)])
self.assertEqual(None, parse_result.parse_tree)
self.assertEqual("double s", parse_result.error.code)
def test_conflict_error(self):
self.assertRaises(
parser.ParserGenerationError,
parser.generate_parser,
"C", _parse_productions("C -> S", "C -> D", "S -> a", "D -> a"), [])
def test_bad_mark_error(self):
self.assertRaises(parser.ParserGenerationError,
parser.generate_parser,
"C", _parse_productions("C -> s", "C -> d"),
[([parser_types.Token("s", "s", None),
parser_types.Token("s", "s", None)],
parser_types.Token("s", "s", None),
"double s", "ss"),
([parser_types.Token("s", "s", None),
parser_types.Token("s", "s", None)],
parser_types.Token("s", "s", None),
"double 's'", "ss")])
self.assertRaises(parser.ParserGenerationError,
parser.generate_parser,
"C", _parse_productions("C -> s", "C -> d"),
[([parser_types.Token("s", "s", None)],
parser_types.Token("s", "s", None),
"single s", "s")])
class ModuleParserTest(unittest.TestCase):
"""Tests for parser.parse_module().
Correct parses should mostly be checked in conjunction with
module_ir.build_ir, as the exact data structure returned by
parser.parse_module() is determined by the grammar defined in module_ir.
These tests only need to cover errors and sanity checking.
"""
def test_error_reporting_by_example(self):
parse_result = parser.parse_module(
tokenizer.tokenize("struct LogFileStatus:\n"
" 0 [+4] UInt\n", "")[0])
self.assertEqual(None, parse_result.parse_tree)
self.assertEqual("A name is required for a struct field.",
parse_result.error.code)
self.assertEqual('"\\n"', parse_result.error.token.symbol)
self.assertEqual(set(['"["', "SnakeWord", '"."', '":"', '"("']),
parse_result.error.expected_tokens)
def test_error_reporting_without_example(self):
parse_result = parser.parse_module(
tokenizer.tokenize("struct LogFileStatus:\n"
" 0 [+4] UInt foo +\n", "")[0])
self.assertEqual(None, parse_result.parse_tree)
self.assertEqual(None, parse_result.error.code)
self.assertEqual('"+"', parse_result.error.token.symbol)
self.assertEqual(set(['"("', '"\\n"', '"["', "Documentation", "Comment"]),
parse_result.error.expected_tokens)
def test_ok_parse(self):
parse_result = parser.parse_module(
tokenizer.tokenize("struct LogFileStatus:\n"
" 0 [+4] UInt foo\n", "")[0])
self.assertTrue(parse_result.parse_tree)
self.assertEqual(None, parse_result.error)
if __name__ == "__main__":
unittest.main()