Merge pull request #370 from python-cmd2/ply

Switch parsing logic from pyparsing to shlex

1 files changed, 300 insertions, 261 deletions

diff --git a/tests/test_parsing.py b/tests/test_parsing.py
index b61e2d06..7940bbd8 100644
--- a/tests/test_parsing.py
+++ b/tests/test_parsing.py
@@ -1,327 +1,294 @@
 # coding=utf-8
 """
-Unit/functional testing for helper functions/classes in the cmd2.py module.
-
-These are primarily tests related to parsing.  Moreover, they are mostly a port of the old doctest tests which were
-problematic because they worked properly for some versions of pyparsing but not for others.
+Test the parsing logic in parsing.py
 
 Copyright 2017 Todd Leonhardt <todd.leonhardt@gmail.com>
 Released under MIT license, see LICENSE file
 """
-from cmd2 import cmd2
 import pytest
 
+from cmd2 import cmd2
+from cmd2.parsing import StatementParser
 
-@pytest.fixture
-def hist():
-    from cmd2.cmd2 import HistoryItem
-    h = cmd2.History([HistoryItem('first'), HistoryItem('second'), HistoryItem('third'), HistoryItem('fourth')])
-    return h
+from cmd2 import utils
 
-# Case-sensitive parser
 @pytest.fixture
 def parser():
-    c = cmd2.Cmd()
-    c.multilineCommands = ['multiline']
-    c.parser_manager = cmd2.ParserManager(redirector=c.redirector, terminators=c.terminators,
-                                               multilineCommands=c.multilineCommands, legalChars=c.legalChars,
-                                               commentGrammars=c.commentGrammars, commentInProgress=c.commentInProgress,
-                                               blankLinesAllowed=c.blankLinesAllowed, prefixParser=c.prefixParser,
-                                               preparse=c.preparse, postparse=c.postparse, aliases=c.aliases,
-                                               shortcuts=c.shortcuts)
-    return c.parser_manager.main_parser
-
-# Case-sensitive ParserManager
-@pytest.fixture
-def cs_pm():
-    c = cmd2.Cmd()
-    c.multilineCommands = ['multiline']
-    c.parser_manager = cmd2.ParserManager(redirector=c.redirector, terminators=c.terminators,
-                                               multilineCommands=c.multilineCommands, legalChars=c.legalChars,
-                                               commentGrammars=c.commentGrammars, commentInProgress=c.commentInProgress,
-                                               blankLinesAllowed=c.blankLinesAllowed, prefixParser=c.prefixParser,
-                                               preparse=c.preparse, postparse=c.postparse, aliases=c.aliases,
-                                               shortcuts=c.shortcuts)
-    return c.parser_manager
-
-
-@pytest.fixture
-def input_parser():
-    c = cmd2.Cmd()
-    return c.parser_manager.input_source_parser
-
-
-def test_history_span(hist):
-    h = hist
-    assert h == ['first', 'second', 'third', 'fourth']
-    assert h.span('-2..') == ['third', 'fourth']
-    assert h.span('2..3') == ['second', 'third']    # Inclusive of end
-    assert h.span('3') == ['third']
-    assert h.span(':') == h
-    assert h.span('2..') == ['second', 'third', 'fourth']
-    assert h.span('-1') == ['fourth']
-    assert h.span('-2..-3') == ['third', 'second']
-    assert h.span('*') == h
-
-def test_history_get(hist):
-    h = hist
-    assert h == ['first', 'second', 'third', 'fourth']
-    assert h.get('') == h
-    assert h.get('-2') == h[:-2]
-    assert h.get('5') == []
-    assert h.get('2-3') == ['second']           # Exclusive of end
-    assert h.get('ir') == ['first', 'third']    # Normal string search for all elements containing "ir"
-    assert h.get('/i.*d/') == ['third']         # Regex string search "i", then anything, then "d"
-
-
-def test_cast():
-    cast = cmd2.cast
-
-    # Boolean
-    assert cast(True, True) == True
-    assert cast(True, False) == False
-    assert cast(True, 0) == False
-    assert cast(True, 1) == True
-    assert cast(True, 'on') == True
-    assert cast(True, 'off') == False
-    assert cast(True, 'ON') == True
-    assert cast(True, 'OFF') == False
-    assert cast(True, 'y') == True
-    assert cast(True, 'n') == False
-    assert cast(True, 't') == True
-    assert cast(True, 'f') == False
-
-    # Non-boolean same type
-    assert cast(1, 5) == 5
-    assert cast(3.4, 2.7) == 2.7
-    assert cast('foo', 'bar') == 'bar'
-    assert cast([1,2], [3,4]) == [3,4]
-
-
-def test_cast_problems(capsys):
-    cast = cmd2.cast
-
-    expected = 'Problem setting parameter (now {}) to {}; incorrect type?\n'
-
-    # Boolean current, with new value not convertible to bool
-    current = True
-    new = [True, True]
-    assert cast(current, new) == current
-    out, err = capsys.readouterr()
-    assert out == expected.format(current, new)
-
-    # Non-boolean current, with new value not convertible to current type
-    current = 1
-    new = 'octopus'
-    assert cast(current, new) == current
-    out, err = capsys.readouterr()
-    assert out == expected.format(current, new)
-
+    parser = StatementParser(
+        allow_redirection=True,
+        terminators=[';'],
+        multiline_commands=['multiline'],
+        aliases={'helpalias': 'help',
+                 '42': 'theanswer',
+                 'l': '!ls -al',
+                 'anothermultiline': 'multiline',
+                 'fake': 'pyscript'},
+        shortcuts=[('?', 'help'), ('!', 'shell')]
+    )
+    return parser
 
 def test_parse_empty_string(parser):
-    assert parser.parseString('').dump() == '[]'
-
-def test_parse_only_comment(parser):
-    assert parser.parseString('/* empty command */').dump() == '[]'
-
-def test_parse_single_word(parser):
-    line = 'plainword'
-    results = parser.parseString(line)
-    assert results.command == line
-
-def test_parse_word_plus_terminator(parser):
+    statement = parser.parse('')
+    assert not statement.command
+    assert not statement.args
+    assert statement.raw == ''
+
+@pytest.mark.parametrize('line,tokens', [
+    ('command', ['command']),
+    ('command /* with some comment */ arg', ['command', 'arg']),
+    ('command arg1 arg2 # comment at the end', ['command', 'arg1', 'arg2']),
+    ('42 arg1 arg2', ['theanswer', 'arg1', 'arg2']),
+    ('l', ['shell', 'ls', '-al'])
+])
+def test_tokenize(parser, line, tokens):
+    tokens_to_test = parser.tokenize(line)
+    assert tokens_to_test == tokens
+
+@pytest.mark.parametrize('tokens,command,args', [
+    ([], None, None),
+    (['command'], 'command', None),
+    (['command', 'arg1', 'arg2'], 'command', 'arg1 arg2')
+])
+def test_command_and_args(parser, tokens, command, args):
+    (parsed_command, parsed_args) = parser._command_and_args(tokens)
+    assert command == parsed_command
+    assert args == parsed_args
+
+@pytest.mark.parametrize('line', [
+    'plainword',
+    '"one word"',
+    "'one word'",
+])
+def test_single_word(parser, line):
+    statement = parser.parse(line)
+    assert statement.command == line
+    assert not statement.args
+    assert statement.argv == [utils.strip_quotes(line)]
+
+def test_word_plus_terminator(parser):
     line = 'termbare;'
-    results = parser.parseString(line)
-    assert results.command == 'termbare'
-    assert results.terminator == ';'
+    statement = parser.parse(line)
+    assert statement.command == 'termbare'
+    assert statement.terminator == ';'
+    assert statement.argv == ['termbare']
 
-def test_parse_suffix_after_terminator(parser):
+def test_suffix_after_terminator(parser):
     line = 'termbare; suffx'
-    results = parser.parseString(line)
-    assert results.command == 'termbare'
-    assert results.terminator == ';'
-    assert results.suffix == 'suffx'
+    statement = parser.parse(line)
+    assert statement.command == 'termbare'
+    assert statement.terminator == ';'
+    assert statement.suffix == 'suffx'
+    assert statement.argv == ['termbare']
 
-def test_parse_command_with_args(parser):
+def test_command_with_args(parser):
     line = 'command with args'
-    results = parser.parseString(line)
-    assert results.command == 'command'
-    assert results.args == 'with args'
+    statement = parser.parse(line)
+    assert statement.command == 'command'
+    assert statement.args == 'with args'
+    assert statement.argv == ['command', 'with', 'args']
+
+def test_command_with_quoted_args(parser):
+    line = 'command with "quoted args" and "some not"'
+    statement = parser.parse(line)
+    assert statement.command == 'command'
+    assert statement.args == 'with "quoted args" and "some not"'
+    assert statement.argv == ['command', 'with', 'quoted args', 'and', 'some not']
 
 def test_parse_command_with_args_terminator_and_suffix(parser):
     line = 'command with args and terminator; and suffix'
-    results = parser.parseString(line)
-    assert results.command == 'command'
-    assert results.args == "with args and terminator"
-    assert results.terminator == ';'
-    assert results.suffix == 'and suffix'
-
-def test_parse_simple_piped(parser):
-    line = 'simple | piped'
-    results = parser.parseString(line)
-    assert results.command == 'simple'
-    assert results.pipeTo == " piped"
-
-def test_parse_double_pipe_is_not_a_pipe(parser):
+    statement = parser.parse(line)
+    assert statement.command == 'command'
+    assert statement.args == "with args and terminator"
+    assert statement.terminator == ';'
+    assert statement.suffix == 'and suffix'
+    assert statement.argv == ['command', 'with', 'args', 'and', 'terminator']
+
+def test_hashcomment(parser):
+    statement = parser.parse('hi # this is all a comment')
+    assert statement.command == 'hi'
+    assert not statement.args
+    assert statement.argv == ['hi']
+
+def test_c_comment(parser):
+    statement = parser.parse('hi /* this is | all a comment */')
+    assert statement.command == 'hi'
+    assert not statement.args
+    assert not statement.pipe_to
+    assert statement.argv == ['hi']
+
+def test_c_comment_empty(parser):
+    statement = parser.parse('/* this is | all a comment */')
+    assert not statement.command
+    assert not statement.args
+    assert not statement.pipe_to
+    assert not statement.argv
+
+def test_parse_what_if_quoted_strings_seem_to_start_comments(parser):
+    statement = parser.parse('what if "quoted strings /* seem to " start comments?')
+    assert statement.command == 'what'
+    assert statement.args == 'if "quoted strings /* seem to " start comments?'
+    assert not statement.pipe_to
+    assert statement.argv == ['what', 'if', 'quoted strings /* seem to ', 'start', 'comments?']
+
+def test_simple_piped(parser):
+    statement = parser.parse('simple | piped')
+    assert statement.command == 'simple'
+    assert not statement.args
+    assert statement.argv == ['simple']
+    assert statement.pipe_to == 'piped'
+
+def test_double_pipe_is_not_a_pipe(parser):
     line = 'double-pipe || is not a pipe'
-    results = parser.parseString(line)
-    assert results.command == 'double-pipe'
-    assert results.args == '|| is not a pipe'
-    assert not 'pipeTo' in results
+    statement = parser.parse(line)
+    assert statement.command == 'double-pipe'
+    assert statement.args == '|| is not a pipe'
+    assert statement.argv == ['double-pipe', '||', 'is', 'not', 'a', 'pipe']
+    assert not statement.pipe_to
 
-def test_parse_complex_pipe(parser):
+def test_complex_pipe(parser):
     line = 'command with args, terminator;sufx | piped'
-    results = parser.parseString(line)
-    assert results.command == 'command'
-    assert results.args == "with args, terminator"
-    assert results.terminator == ';'
-    assert results.suffix == 'sufx'
-    assert results.pipeTo == ' piped'
-
-def test_parse_output_redirect(parser):
+    statement = parser.parse(line)
+    assert statement.command == 'command'
+    assert statement.args == "with args, terminator"
+    assert statement.argv == ['command', 'with', 'args,', 'terminator']
+    assert statement.terminator == ';'
+    assert statement.suffix == 'sufx'
+    assert statement.pipe_to == 'piped'
+
+def test_output_redirect(parser):
     line = 'output into > afile.txt'
-    results = parser.parseString(line)
-    assert results.command == 'output'
-    assert results.args == 'into'
-    assert results.output == '>'
-    assert results.outputTo == 'afile.txt'
-
-def test_parse_output_redirect_with_dash_in_path(parser):
+    statement = parser.parse(line)
+    assert statement.command == 'output'
+    assert statement.args == 'into'
+    assert statement.argv == ['output', 'into']
+    assert statement.output == '>'
+    assert statement.output_to == 'afile.txt'
+
+def test_output_redirect_with_dash_in_path(parser):
     line = 'output into > python-cmd2/afile.txt'
-    results = parser.parseString(line)
-    assert results.command == 'output'
-    assert results.args == 'into'
-    assert results.output == '>'
-    assert results.outputTo == 'python-cmd2/afile.txt'
-
-
-def test_case_sensitive_parsed_single_word(cs_pm):
-    line = 'HeLp'
-    statement = cs_pm.parsed(line)
-    assert statement.parsed.command == line
-
-
-def test_parse_input_redirect(input_parser):
-    line = '< afile.txt'
-    results = input_parser.parseString(line)
-    assert results.inputFrom == line
-
-def test_parse_input_redirect_with_dash_in_path(input_parser):
-    line = "< python-cmd2/afile.txt"
-    results = input_parser.parseString(line)
-    assert results.inputFrom == line
-
-def test_parse_pipe_and_redirect(parser):
+    statement = parser.parse(line)
+    assert statement.command == 'output'
+    assert statement.args == 'into'
+    assert statement.argv == ['output', 'into']
+    assert statement.output == '>'
+    assert statement.output_to == 'python-cmd2/afile.txt'
+
+def test_output_redirect_append(parser):
+    line = 'output appended to >> /tmp/afile.txt'
+    statement = parser.parse(line)
+    assert statement.command == 'output'
+    assert statement.args == 'appended to'
+    assert statement.argv == ['output', 'appended', 'to']
+    assert statement.output == '>>'
+    assert statement.output_to == '/tmp/afile.txt'
+
+def test_pipe_and_redirect(parser):
     line = 'output into;sufx | pipethrume plz > afile.txt'
-    results = parser.parseString(line)
-    assert results.command == 'output'
-    assert results.args == 'into'
-    assert results.terminator == ';'
-    assert results.suffix == 'sufx'
-    assert results.pipeTo == ' pipethrume plz'
-    assert results.output == '>'
-    assert results.outputTo == 'afile.txt'
+    statement = parser.parse(line)
+    assert statement.command == 'output'
+    assert statement.args == 'into'
+    assert statement.argv == ['output', 'into']
+    assert statement.terminator == ';'
+    assert statement.suffix == 'sufx'
+    assert statement.pipe_to == 'pipethrume plz'
+    assert statement.output == '>'
+    assert statement.output_to == 'afile.txt'
 
 def test_parse_output_to_paste_buffer(parser):
     line = 'output to paste buffer >> '
-    results = parser.parseString(line)
-    assert results.command == 'output'
-    assert results.args == 'to paste buffer'
-    assert results.output == '>>'
-
-def test_parse_ignore_commented_redirectors(parser):
-    line = 'ignore the /* commented | > */ stuff;'
-    results = parser.parseString(line)
-    assert results.command == 'ignore'
-    assert results.args == 'the /* commented | > */ stuff'
-    assert results.terminator == ';'
-
-def test_parse_has_redirect_inside_terminator(parser):
+    statement = parser.parse(line)
+    assert statement.command == 'output'
+    assert statement.args == 'to paste buffer'
+    assert statement.argv == ['output', 'to', 'paste', 'buffer']
+    assert statement.output == '>>'
+
+def test_has_redirect_inside_terminator(parser):
     """The terminator designates the end of the commmand/arguments portion.  If a redirector
     occurs before a terminator, then it will be treated as part of the arguments and not as a redirector."""
     line = 'has > inside;'
-    results = parser.parseString(line)
-    assert results.command == 'has'
-    assert results.args == '> inside'
-    assert results.terminator == ';'
-
-def test_parse_what_if_quoted_strings_seem_to_start_comments(parser):
-    line = 'what if "quoted strings /* seem to " start comments?'
-    results = parser.parseString(line)
-    assert results.command == 'what'
-    assert results.args == 'if "quoted strings /* seem to " start comments?'
+    statement = parser.parse(line)
+    assert statement.command == 'has'
+    assert statement.args == '> inside'
+    assert statement.argv == ['has', '>', 'inside']
+    assert statement.terminator == ';'
 
 def test_parse_unfinished_multiliine_command(parser):
     line = 'multiline has > inside an unfinished command'
-    results = parser.parseString(line)
-    assert results.multilineCommand == 'multiline'
-    assert not 'args' in results
+    statement = parser.parse(line)
+    assert statement.multiline_command == 'multiline'
+    assert statement.command == 'multiline'
+    assert statement.args == 'has > inside an unfinished command'
+    assert statement.argv == ['multiline', 'has', '>', 'inside', 'an', 'unfinished', 'command']
+    assert not statement.terminator
 
 def test_parse_multiline_command_ignores_redirectors_within_it(parser):
     line = 'multiline has > inside;'
-    results = parser.parseString(line)
-    assert results.multilineCommand == 'multiline'
-    assert results.args == 'has > inside'
-    assert results.terminator == ';'
+    statement = parser.parse(line)
+    assert statement.multiline_command == 'multiline'
+    assert statement.args == 'has > inside'
+    assert statement.argv == ['multiline', 'has', '>', 'inside']
+    assert statement.terminator == ';'
 
 def test_parse_multiline_with_incomplete_comment(parser):
     """A terminator within a comment will be ignored and won't terminate a multiline command.
     Un-closed comments effectively comment out everything after the start."""
     line = 'multiline command /* with comment in progress;'
-    results = parser.parseString(line)
-    assert results.multilineCommand == 'multiline'
-    assert not 'args' in results
+    statement = parser.parse(line)
+    assert statement.multiline_command == 'multiline'
+    assert statement.command == 'multiline'
+    assert statement.args == 'command'
+    assert statement.argv == ['multiline', 'command']
+    assert not statement.terminator
 
 def test_parse_multiline_with_complete_comment(parser):
     line = 'multiline command /* with comment complete */ is done;'
-    results = parser.parseString(line)
-    assert results.multilineCommand == 'multiline'
-    assert results.args == 'command /* with comment complete */ is done'
-    assert results.terminator == ';'
+    statement = parser.parse(line)
+    assert statement.multiline_command == 'multiline'
+    assert statement.command == 'multiline'
+    assert statement.args == 'command is done'
+    assert statement.argv == ['multiline', 'command', 'is', 'done']
+    assert statement.terminator == ';'
 
 def test_parse_multiline_termninated_by_empty_line(parser):
     line = 'multiline command ends\n\n'
-    results = parser.parseString(line)
-    assert results.multilineCommand == 'multiline'
-    assert results.args == 'command ends'
-    assert len(results.terminator) == 2
-    assert results.terminator[0] == '\n'
-    assert results.terminator[1] == '\n'
+    statement = parser.parse(line)
+    assert statement.multiline_command == 'multiline'
+    assert statement.command == 'multiline'
+    assert statement.args == 'command ends'
+    assert statement.argv == ['multiline', 'command', 'ends']
+    assert statement.terminator == '\n'
 
 def test_parse_multiline_ignores_terminators_in_comments(parser):
     line = 'multiline command "with term; ends" now\n\n'
-    results = parser.parseString(line)
-    assert results.multilineCommand == 'multiline'
-    assert results.args == 'command "with term; ends" now'
-    assert len(results.terminator) == 2
-    assert results.terminator[0] == '\n'
-    assert results.terminator[1] == '\n'
+    statement = parser.parse(line)
+    assert statement.multiline_command == 'multiline'
+    assert statement.command == 'multiline'
+    assert statement.args == 'command "with term; ends" now'
+    assert statement.argv == ['multiline', 'command', 'with term; ends', 'now']
+    assert statement.terminator == '\n'
 
 def test_parse_command_with_unicode_args(parser):
     line = 'drink café'
-    results = parser.parseString(line)
-    assert results.command == 'drink'
-    assert results.args == 'café'
+    statement = parser.parse(line)
+    assert statement.command == 'drink'
+    assert statement.args == 'café'
+    assert statement.argv == ['drink', 'café']
 
 def test_parse_unicode_command(parser):
     line = 'café au lait'
-    results = parser.parseString(line)
-    assert results.command == 'café'
-    assert results.args == 'au lait'
+    statement = parser.parse(line)
+    assert statement.command == 'café'
+    assert statement.args == 'au lait'
+    assert statement.argv == ['café', 'au', 'lait']
 
 def test_parse_redirect_to_unicode_filename(parser):
     line = 'dir home > café'
-    results = parser.parseString(line)
-    assert results.command == 'dir'
-    assert results.args == 'home'
-    assert results.output == '>'
-    assert results.outputTo == 'café'
-
-def test_parse_input_redirect_from_unicode_filename(input_parser):
-    line = '< café'
-    results = input_parser.parseString(line)
-    assert results.inputFrom == line
-
+    statement = parser.parse(line)
+    assert statement.command == 'dir'
+    assert statement.args == 'home'
+    assert statement.argv == ['dir', 'home']
+    assert statement.output == '>'
+    assert statement.output_to == 'café'
 
 def test_empty_statement_raises_exception():
     app = cmd2.Cmd()
@@ -330,3 +297,75 @@ def test_empty_statement_raises_exception():
 
     with pytest.raises(cmd2.EmptyStatement):
         app._complete_statement(' ')
+
+@pytest.mark.parametrize('line,command,args', [
+    ('helpalias', 'help', None),
+    ('helpalias mycommand', 'help', 'mycommand'),
+    ('42', 'theanswer', None),
+    ('42 arg1 arg2', 'theanswer', 'arg1 arg2'),
+    ('!ls', 'shell', 'ls'),
+    ('!ls -al /tmp', 'shell', 'ls -al /tmp'),
+    ('l', 'shell', 'ls -al')
+])
+def test_alias_and_shortcut_expansion(parser, line, command, args):
+    statement = parser.parse(line)
+    assert statement.command == command
+    assert statement.args == args
+
+def test_alias_on_multiline_command(parser):
+    line = 'anothermultiline has > inside an unfinished command'
+    statement = parser.parse(line)
+    assert statement.multiline_command == 'multiline'
+    assert statement.command == 'multiline'
+    assert statement.args == 'has > inside an unfinished command'
+    assert not statement.terminator
+
+def test_parse_command_only_command_and_args(parser):
+    line = 'help history'
+    statement = parser.parse_command_only(line)
+    assert statement.command == 'help'
+    assert statement.args == 'history'
+    assert statement.argv == ['help', 'history']
+    assert statement.command_and_args == line
+
+def test_parse_command_only_emptyline(parser):
+    line = ''
+    statement = parser.parse_command_only(line)
+    # statement is a subclass of str(), the value of the str
+    # should be '', to retain backwards compatibility with
+    # the cmd in the standard library
+    assert statement == ''
+    assert statement.command is None
+    assert statement.args is None
+    assert not statement.argv
+    assert statement.command_and_args == None
+
+def test_parse_command_only_strips_line(parser):
+    line = '  help history  '
+    statement = parser.parse_command_only(line)
+    assert statement.command == 'help'
+    assert statement.args == 'history'
+    assert statement.argv == ['help', 'history']
+    assert statement.command_and_args == line.strip()
+
+def test_parse_command_only_expands_alias(parser):
+    line = 'fake foobar.py'
+    statement = parser.parse_command_only(line)
+    assert statement.command == 'pyscript'
+    assert statement.args == 'foobar.py'
+    assert statement.argv == ['pyscript', 'foobar.py']
+
+def test_parse_command_only_expands_shortcuts(parser):
+    line = '!cat foobar.txt'
+    statement = parser.parse_command_only(line)
+    assert statement.command == 'shell'
+    assert statement.args == 'cat foobar.txt'
+    assert statement.argv == ['shell', 'cat', 'foobar.txt']
+    assert statement.command_and_args == 'shell cat foobar.txt'
+
+def test_parse_command_only_quoted_args(parser):
+    line = 'l "/tmp/directory with spaces/doit.sh"'
+    statement = parser.parse_command_only(line)
+    assert statement.command == 'shell'
+    assert statement.args == 'ls -al "/tmp/directory with spaces/doit.sh"'
+    assert statement.command_and_args == line.replace('l', 'shell ls -al')