def parse(cls, ctx, tokens, npargs, flags, breakstack, sortable=False):
"""
Parse a continuous sequence of `npargs` positional arguments. If npargs is
an integer we will consume exactly that many arguments. If it is not an
integer then it is a string meaning:
* "?": zero or one
* "*": zero or more
* "+": one or more
"""
tree = cls(sortable=sortable)
tree.spec = PositionalSpec(npargs, flags)
nconsumed = 0
# Strip off any preceeding whitespace (note that in most cases this has
# already been done but in some cases (such ask kwarg subparser) where
# it hasn't
while tokens and tokens[0].type in WHITESPACE_TOKENS:
tree.children.append(tokens.pop(0))
# If the first non-whitespace token is a cmake-format tag annotating
# sortability, then parse it out here and record the annotation
if tokens and get_tag(tokens[0]) in ("sortable", "sort"):
tree.sortable = True
elif tokens and get_tag(tokens[0]) in ("unsortable", "unsort"):
tree.sortable = False
while tokens:
# Break if we have consumed enough positional arguments
if pargs_are_full(npargs, nconsumed):
break
# Break if the next token belongs to a parent parser, i.e. if it
# matches a keyword argument of something higher in the stack, or if
# it closes a parent group.
if should_break(tokens[0], breakstack):
# NOTE(josh): if npargs is an exact number of arguments, then we
# shouldn't break on kwarg match from a parent parser. Instead, we
# should consume the token. This is a hack to deal with
# ```install(RUNTIME COMPONENT runtime)``. In this case the second
# occurance of "runtime" should not match the ``RUNTIME`` keyword
# and should not break the positional parser.
# TODO(josh): this is kind of hacky because it will force the positional
# parser to consume a right parenthesis and will lead to parse errors
# in the event of a missing positional argument. Such errors will be
# difficult to debug for the user.
if not npargs_is_exact(npargs):
break
if tokens[0].type == lexer.TokenType.RIGHT_PAREN:
break
# If this is the start of a parenthetical group, then parse the group
# NOTE(josh): syntatically this probably shouldn't be allowed here, but
# cmake seems to accept it so we probably should too.
if tokens[0].type == lexer.TokenType.LEFT_PAREN:
subtree = ParenGroupNode.parse(ctx, tokens, breakstack)
tree.children.append(subtree)
continue
# If it is a whitespace token then put it directly in the parse tree at
# the current depth
if tokens[0].type in WHITESPACE_TOKENS:
tree.children.append(tokens.pop(0))
continue
# If it's a comment token not associated with an argument, then put it
# directly into the parse tree at the current depth
if tokens[0].type in (lexer.TokenType.COMMENT,
lexer.TokenType.BRACKET_COMMENT):
before = len(tokens)
child = CommentNode.consume(ctx, tokens)
assert len(tokens) < before, \
"consume_comment didn't consume any tokens"
tree.children.append(child)
continue
# Otherwise is it is a positional argument, so add it to the tree as such
if get_normalized_kwarg(tokens[0]) in flags:
child = TreeNode(NodeType.FLAG)
else:
child = TreeNode(NodeType.ARGUMENT)
child.children.append(tokens.pop(0))
CommentNode.consume_trailing(ctx, tokens, child)
tree.children.append(child)
nconsumed += 1
return tree
def parse2(cls, ctx, tokens, cmdspec, kwargs, breakstack):
"""
Standard parser for the commands in the form of::
command_name(parg1 parg2 parg3...
KEYWORD1 kwarg1 kwarg2...
KEYWORD2 kwarg3 kwarg4...
FLAG1 FLAG2 FLAG3)
The parser starts off as a positional parser. If a keyword or flag is
encountered the positional parser is popped off the parse stack. If it was
a keyword then the keyword parser is pushed on the parse stack. If it was
a flag than a new flag parser is pushed onto the stack.
"""
# NOTE(josh): we will pop things off this list, so let's make a copy
pargspecs = list(cmdspec.pargs)
tree = cls()
tree.cmdspec = cmdspec
# If it is a whitespace token then put it directly in the parse tree at
# the current depth
while tokens and tokens[0].type in WHITESPACE_TOKENS:
tree.children.append(tokens.pop(0))
continue
# NOTE(josh): if there is only one non-exact legacy specification then we
# reuse that specification for any additional positional arguments that we
# pick up. This is to maintain the current/legacy behavior of simple
# positional argument specifications
# TODO(josh): double check the reasoning for this. I think it might be
# mistaken and unnecessary
default_spec = DEFAULT_PSPEC
if (len(pargspecs) == 1 and pargspecs[0].legacy
and not npargs_is_exact(pargspecs[0].nargs)):
default_spec = pargspecs.pop(0)
all_flags = list(default_spec.flags)
for pspec in pargspecs:
all_flags.extend(pspec.flags)
kwarg_breakstack = breakstack + [
KwargBreaker(list(kwargs.keys()) + all_flags)
]
while tokens:
# If it is a whitespace token then put it directly in the parse tree at
# the current depth
if tokens[0].type in WHITESPACE_TOKENS:
tree.children.append(tokens.pop(0))
continue
# If it's a comment, then add it at the current depth
if tokens[0].type in (lexer.TokenType.COMMENT,
lexer.TokenType.BRACKET_COMMENT):
if comment_belongs_up_tree(ctx, tokens, tree, breakstack):
break
tree.children.append(CommentNode.consume(ctx, tokens))
continue
# If it's a sentinel comment, then add it at the current depth
if tokens[0].type in (lexer.TokenType.FORMAT_OFF,
lexer.TokenType.FORMAT_ON):
tree.children.append(OnOffNode.consume(ctx, tokens))
continue
# Break if the next token belongs to a parent parser, i.e. if it
# matches a keyword argument of something higher in the stack, or if
# it closes a parent group.
if should_break(tokens[0], breakstack):
# NOTE(josh): if spec.nargs is an exact number of arguments, then we
# shouldn't break on kwarg match from a parent parser. Instead, we
# should consume that many tokens. This is a hack to deal with
# ```install(RUNTIME COMPONENT runtime)``. In this case the second
# occurance of "runtime" should not match the ``RUNTIME`` keyword
# and should not break the positional parser.
# TODO(josh): this is kind of hacky because it will force the positional
# parser to consume a right parenthesis and will lead to parse errors
# in the event of a missing positional argument. Such errors will be
# difficult to debug for the user.
if pargspecs:
pspec = pargspecs[0]
else:
pspec = default_spec
if not npargs_is_exact(pspec.nargs) or pspec.nargs == 0:
break
ntokens = len(tokens)
word = get_normalized_kwarg(tokens[0])
if word in kwargs:
with ctx.pusharg(tree):
subtree = KeywordGroupNode.parse(ctx, tokens, word,
kwargs[word],
kwarg_breakstack)
tree.kwarg_groups.append(subtree)
else:
if pargspecs:
pspec = pargspecs.pop(0)
else:
pspec = default_spec
other_flags = []
for otherspec in pargspecs:
for flag in otherspec.flags:
if flag in pspec.flags:
continue
other_flags.append(flag)
positional_breakstack = breakstack + [
KwargBreaker(list(kwargs.keys()) + other_flags)
]
with ctx.pusharg(tree):
subtree = PositionalGroupNode.parse2(
ctx, tokens, pspec, positional_breakstack)
tree.parg_groups.append(subtree)
if len(tokens) >= ntokens:
raise InternalError(
"parsed an empty subtree at {}:\n {}\n pspec: {}".format(
tokens[0], dump_tree_tostr([tree]), pspec))
tree.children.append(subtree)
return tree