android13/build/bazel/scripts/difftool/commands.py

146 lines
4.1 KiB
Python

#!/usr/bin/env python3
#
# Copyright (C) 2022 The Android Open Source Project
#
# 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."""
"""Helper functions and types for command processing for difftool."""
class CommandInfo:
"""Contains information about an action commandline."""
def __init__(self, tool, args):
self.tool = tool
self.args = args
def __str__(self):
s = "CommandInfo:\n"
s += " Tool:\n"
s += " " + self.tool + "\n"
s += " Args:\n"
for x in self.args:
s += " " + x + "\n"
return s
def parse_flag_groups(args, custom_flag_group=None):
"""Returns a list of flag groups based on the given args.
An arg group consists of one-arg flags, two-arg groups, or positional args.
Positional arguments (for example `a.out`) are returned as strings in the
list.
One-arg groups consist of a flag with no argument (for example, `--verbose`),
and are returned as a tuple of size one in the list.
Two-arg groups consist of a flag with a single argument (for example,
`--file bar.txt` or `--mode=verbose`),
and are returned as a tuple of size two in the list.
Also accepts an optional function `custom_flag_group` to determine if a
single arg comprises a group. (custom_flag_group(x) should return a flag
group abiding by the above convention, or None to use non-custom logic.
This may be required to accurately parse arg groups. For example, `-a b` may
be either a one-arg group `-a` followed by a positonal group `b`, or a two-arg
group `-a b`."""
flag_groups = []
i = 0
while i < len(args):
if custom_flag_group:
g = custom_flag_group(args[i])
if g is not None:
flag_groups += [g]
i += 1
continue
g = one_arg_group(args[i])
if g is not None:
flag_groups += [g]
i += 1
continue
# Look for a two-arg group if there are at least 2 elements left.
if i < len(args) - 1:
g = two_arg_group(args[i], args[i+1])
if g is not None:
flag_groups += [g]
i += 2
continue
# Not a recognized one arg group or two arg group.
if args[i].startswith("-"):
flag_groups += [(args[i])]
else:
flag_groups += [args[i]]
i += 1
return flag_groups
def remove_hyphens(x):
"""Returns the given string with leading '--' or '-' removed."""
if x.startswith("--"):
return x[2:]
elif x.startswith("-"):
return x[1:]
else:
return x
def two_arg_group(a, b):
"""Determines whether two consecutive args belong to a single flag group.
Two arguments belong to a single flag group if the first arg contains
a hyphen and the second does not. For example: `-foo bar` is a flag,
but `foo bar` and `--foo --bar` are not.
Returns:
A tuple of the two args without hyphens if they belong to a single
flag, or None if they do not. """
if a.startswith("-") and (not b.startswith("-")):
return (remove_hyphens(a), b)
else:
return None
def one_arg_group(x):
"""Determines whether an arg comprises a complete flag group.
An argument comprises a single flag group if it is of the form of
`-key=value` or `--key=value`.
Returns:
A tuple of `(key, value)` of the flag group, if the arg comprises a
complete flag group, or None if it does not."""
tokens = x.split("=")
if len(tokens) == 2:
return (remove_hyphens(tokens[0]), tokens[1])
else:
return None
def is_flag_starts_with(prefix, x):
if isinstance(x, tuple):
return x[0].startswith(prefix)
else:
return x.startswith("--" + prefix) or x.startswith("-" + prefix)
def flag_repr(x):
if isinstance(x, tuple):
return f"-{x[0]} {x[1]}"
else:
return x