dhparser.py

#!/usr/bin/python

"""dhparser.py - command line tool for DHParser

Copyright 2016  by Eckhart Arnold (arnold@badw.de)
                Bavarian Academy of Sciences an Humanities (badw.de)

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

    http://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.
"""

#  TODO: This is still a stub...

import os
import sys

from DHParser.dsl import compileDSL, compile_on_disk
from DHParser.ebnf import get_ebnf_grammar, get_ebnf_transformer, get_ebnf_compiler
from DHParser.parse import compile_source
from DHParser.toolkit import logging

EBNF_TEMPLATE = r"""-grammar

#######################################################################
#
#  EBNF-Directives
#
#######################################################################

@ whitespace  = vertical        # implicit whitespace, includes any number of line feeds
@ literalws   = right           # literals have implicit whitespace on the right hand side
@ comment     = /#.*/           # comments range from a '#'-character to the end of the line
@ ignorecase  = False           # literals and regular expressions are case-sensitive


#######################################################################
#
#  Structure and Components
#
#######################################################################

document = //~ { WORD } §EOF    # root parser: a sequence of words preceded by whitespace
                                # until the end of file

#######################################################################
#
#  Regular Expressions
#
#######################################################################

WORD     =  /\w+/~      # a sequence of letters, optional trailing whitespace
EOF      =  !/./        # no more characters ahead, end of file reached
"""

TEST_WORD_TEMPLATE = r'''[match:WORD]
M1: word
M2: one_word_with_underscores

[fail:WORD]
F1: two words
'''

TEST_DOCUMENT_TEMPLATE = r'''[match:document]
M1: """This is a sequence of words
    extending over several lines"""

[fail:document]
F1: """This test should fail, because neither
    comma nor full have been defined anywhere."""
'''

README_TEMPLATE = """# {name}

PLACE A SHORT DESCRIPTION HERE

Author: AUTHOR'S NAME <EMAIL>, AFFILIATION


## License

{name} is open source software under the [Apache 2.0 License](https://www.apache.org/licenses/LICENSE-2.0)

Copyright YEAR AUTHOR'S NAME <EMAIL>, AFFILIATION

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.
"""


GRAMMAR_TEST_TEMPLATE = r'''#!/usr/bin/python3

"""tst_{name}_grammar.py - runs the unit tests for the {name}-grammar
"""

import sys

import DHParser.dsl
from DHParser import testing
from DHParser import toolkit

# recompiles Grammar only if it has changed
if not DHParser.dsl.recompile_grammar('{name}.ebnf', force=False):
    print('\nErrors while recompiling "{name}.ebnf":\n--------------------------------------\n\n')
    with open('{name}_ebnf_ERRORS.txt') as f:
        print(f.read())
    sys.exit(1)

sys.path.append('./')
# must be appended after module creation, because
# otherwise an ImportError is raised under Windows
from {name}Compiler import get_grammar, get_transformer

with toolkit.logging(True):
    error_report = testing.grammar_suite('grammar_tests', get_grammar,
                                         get_transformer, report=True, verbose=True)
if error_report:
    print('\n')
    print(error_report)
    sys.exit(1)
else:
    print('ready.')
'''


def create_project(path: str):
    """Creates the a new DHParser-project in the given `path`.
    """
    def create_file(name, content):
        """Create a file with `name` and write `content` to file."""
        if not os.path.exists(name):
            print('Creating file "%s".' % name)
            with open(name, 'w') as f:
                f.write(content)
        else:
            print('"%s" already exists! Not overwritten.' % name)

    if os.path.exists(path) and not os.path.isdir(path):
        print('Cannot create new project, because a file named "%s" already exists!' % path)
        sys.exit(1)
    name = os.path.basename(path)
    print('Creating new DHParser-project "%s".' % name)
    if not os.path.exists(path):
        os.mkdir(path)
    curr_dir = os.getcwd()
    os.chdir(path)
    if os.path.exists('grammar_tests'):
        if not os.path.isdir('grammar_tests'):
            print('Cannot overwrite existing file "grammar_tests"')
            sys.exit(1)
    else:
        os.mkdir('grammar_tests')

    create_file(os.path.join('grammar_tests', '01_test_word.ini'), TEST_WORD_TEMPLATE)
    create_file(os.path.join('grammar_tests', '02_test_document.ini'), TEST_DOCUMENT_TEMPLATE)
    create_file(name + '.ebnf', '# ' + name + EBNF_TEMPLATE)
    create_file('README.md', README_TEMPLATE.format(name=name))
    create_file('tst_%s_grammar.py' % name, GRAMMAR_TEST_TEMPLATE.format(name=name))
    os.chmod('tst_%s_grammar.py' % name, 0o755)
    os.chdir(curr_dir)
    print('ready.')


def selftest() -> bool:
    """Run a simple self-text of DHParser.
    """
    print("DHParser selftest...")
    print("\nSTAGE I:  Trying to compile EBNF-Grammar:\n")
    builtin_ebnf_parser = get_ebnf_grammar()
    ebnf_src = builtin_ebnf_parser.__doc__[builtin_ebnf_parser.__doc__.find('#'):]
    ebnf_transformer = get_ebnf_transformer()
    ebnf_compiler = get_ebnf_compiler('EBNF')
    generated_ebnf_parser, errors, _ = compile_source(
        ebnf_src, None,
        builtin_ebnf_parser, ebnf_transformer, ebnf_compiler)

    if errors:
        print("Selftest FAILED :-(")
        print("\n\n".join(str(err) for err in errors))
        return False
    print(generated_ebnf_parser)
    print("\n\nSTAGE 2: Selfhosting-test: "
          "Trying to compile EBNF-Grammar with generated parser...\n")
    selfhosted_ebnf_parser = compileDSL(ebnf_src, None, generated_ebnf_parser,
                                        ebnf_transformer, ebnf_compiler)
    ebnf_compiler.gen_transformer_skeleton()
    print(selfhosted_ebnf_parser)
    print("\n\n Selftest SUCCEEDED :-)\n\n")
    return True


def cpu_profile(func, repetitions=1):
    """Profile the function `func`.
    """
    import cProfile
    import pstats
    profile = cProfile.Profile()
    profile.enable()
    for _ in range(repetitions):
        success = func()
        if not success:
            break
    profile.disable()
    # after your program ends
    stats = pstats.Stats(profile)
    stats.strip_dirs()
    stats.sort_stats('time').print_stats(40)
    return success


def mem_profile(func):
    """Profile memory usage of `func`.
    """
    import tracemalloc
    tracemalloc.start()
    success = func()
    snapshot = tracemalloc.take_snapshot()
    top_stats = snapshot.statistics('lineno')
    print("[ Top 20 ]")
    for stat in top_stats[:20]:
        print(stat)
    return success


def main():
    """Creates a project (if a project name has been passed as command line
    parameter) or runs a quick self-test.
    """
    if len(sys.argv) > 1:
        if os.path.exists(sys.argv[1]) and os.path.isfile(sys.argv[1]):
            _errors = compile_on_disk(sys.argv[1],
                                      sys.argv[2] if len(sys.argv) > 2 else "")
            if _errors:
                print('\n\n'.join(str(err) for err in _errors))
                sys.exit(1)
        else:
            create_project(sys.argv[1])
    else:
        # run self test
        # selftest('EBNF/EBNF.ebnf')
        with logging(False):
            if not cpu_profile(selftest, 1):
                sys.exit(1)


if __name__ == "__main__":
    main()