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# vim: set ts=8 sts=4 et sw=4 tw=99:
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
# ----------------------------------------------------------------------------
# This script checks various aspects of SpiderMonkey code style. The current checks are as
# follows.
#
# We check the following things in headers.
#
# - No cyclic dependencies.
#
# - No normal header should #include a inlines.h/-inl.h file.
#
# - #ifndef wrappers should have the right form. (XXX: not yet implemented)
# - Every header file should have one.
# - The guard name used should be appropriate for the filename.
#
# We check the following things in all files.
#
# - #includes should have full paths, e.g. "jit/Ion.h", not "Ion.h".
#
# - #includes should use the appropriate form for system headers (<...>) and
# local headers ("...").
#
# - #includes should be ordered correctly.
# - Each one should be in the correct section.
# - Alphabetical order should be used within sections.
# - Sections should be in the right order.
# Note that the presence of #if/#endif blocks complicates things, to the
# point that it's not always clear where a conditionally-compiled #include
# statement should go, even to a human. Therefore, we check the #include
# statements within each #if/#endif block (including nested ones) in
# isolation, but don't try to do any order checking between such blocks.
# ----------------------------------------------------------------------------
import difflib
import os
import re
import sys
# We don't bother checking files in these directories, because they're (a) auxiliary or (b)
# imported code that doesn't follow our coding style.
ignored_js_src_dirs = [
"js/src/config/", # auxiliary stuff
"js/src/ctypes/libffi/", # imported code
"js/src/devtools/", # auxiliary stuff
"js/src/editline/", # imported code
"js/src/gdb/", # auxiliary stuff
"js/src/vtune/", # imported code
"js/src/zydis/", # imported code
]
# We ignore #includes of these files, because they don't follow the usual rules.
included_inclnames_to_ignore = set(
[
"ffi.h", # generated in ctypes/libffi/
"devtools/Instruments.h", # we ignore devtools/ in general
"double-conversion/double-conversion.h", # strange MFBT case
"javascript-trace.h", # generated in $OBJDIR if HAVE_DTRACE is defined
"frontend/ReservedWordsGenerated.h", # generated in $OBJDIR
"frontend/smoosh_generated.h", # generated in $OBJDIR
"gc/StatsPhasesGenerated.h", # generated in $OBJDIR
"gc/StatsPhasesGenerated.inc", # generated in $OBJDIR
"jit/ABIFunctionTypeGenerated.h", # generated in $OBJDIR"
"jit/AtomicOperationsGenerated.h", # generated in $OBJDIR
"jit/CacheIROpsGenerated.h", # generated in $OBJDIR
"jit/LIROpsGenerated.h", # generated in $OBJDIR
"jit/MIROpsGenerated.h", # generated in $OBJDIR
"js/PrefsGenerated.h", # generated in $OBJDIR
"js/ProfilingCategoryList.h", # comes from mozglue/baseprofiler
"mozilla/glue/Debug.h", # comes from mozglue/misc, shadowed by <mozilla/Debug.h>
"jscustomallocator.h", # provided by embedders; allowed to be missing
"js-config.h", # generated in $OBJDIR
"fdlibm.h", # fdlibm
"FuzzerDefs.h", # included without a path
"FuzzingInterface.h", # included without a path
"ICU4XGraphemeClusterSegmenter.h", # ICU4X
"ICU4XSentenceSegmenter.h", # ICU4X
"ICU4XWordSegmenter.h", # ICU4X
"mozmemory.h", # included without a path
"pratom.h", # NSPR
"prcvar.h", # NSPR
"prerror.h", # NSPR
"prinit.h", # NSPR
"prio.h", # NSPR
"private/pprio.h", # NSPR
"prlink.h", # NSPR
"prlock.h", # NSPR
"prprf.h", # NSPR
"prthread.h", # NSPR
"prtypes.h", # NSPR
"selfhosted.out.h", # generated in $OBJDIR
"shellmoduleloader.out.h", # generated in $OBJDIR
"unicode/locid.h", # ICU
"unicode/uchar.h", # ICU
"unicode/uniset.h", # ICU
"unicode/unistr.h", # ICU
"unicode/utypes.h", # ICU
"vtune/VTuneWrapper.h", # VTune
"wasm/WasmBuiltinModuleGenerated.h", # generated in $OBJDIR"
"zydis/ZydisAPI.h", # Zydis
]
)
deprecated_inclnames = {
"mozilla/Unused.h": "Use [[nodiscard]] and (void)expr casts instead.",
}
# JSAPI functions should be included through headers from js/public instead of
# using the old, catch-all jsapi.h file.
deprecated_inclnames_in_header = {
"jsapi.h": "Prefer including headers from js/public.",
}
# Temporary exclusions for files which still need to include jsapi.h.
deprecated_inclnames_in_header_excludes = {
"js/src/vm/Compartment-inl.h", # for JS::InformalValueTypeName
"js/src/jsapi-tests/tests.h", # for JS_ValueToSource
}
# These files have additional constraints on where they are #included, so we
# ignore #includes of them when checking #include ordering.
oddly_ordered_inclnames = set(
[
"ctypes/typedefs.h", # Included multiple times in the body of ctypes/CTypes.h
# Included in the body of frontend/TokenStream.h
"frontend/ReservedWordsGenerated.h",
"gc/StatsPhasesGenerated.h", # Included in the body of gc/Statistics.h
"gc/StatsPhasesGenerated.inc", # Included in the body of gc/Statistics.cpp
"psapi.h", # Must be included after "util/WindowsWrapper.h" on Windows
"machine/endian.h", # Must be included after <sys/types.h> on BSD
"process.h", # Windows-specific
"winbase.h", # Must precede other system headers(?)
"windef.h", # Must precede other system headers(?)
"windows.h", # Must precede other system headers(?)
]
)
# The files in tests/style/ contain code that fails this checking in various
# ways. Here is the output we expect. If the actual output differs from
# this, one of the following must have happened.
# - New SpiderMonkey code violates one of the checked rules.
# - The tests/style/ files have changed without expected_output being changed
# accordingly.
# - This script has been broken somehow.
#
expected_output = """\
js/src/tests/style/BadIncludes.h:3: error:
the file includes itself
js/src/tests/style/BadIncludes.h:6: error:
"BadIncludes2.h" is included using the wrong path;
did you forget a prefix, or is the file not yet committed?
js/src/tests/style/BadIncludes.h:8: error:
<tests/style/BadIncludes2.h> should be included using
the #include "..." form
js/src/tests/style/BadIncludes.h:10: error:
"stdio.h" is included using the wrong path;
did you forget a prefix, or is the file not yet committed?
js/src/tests/style/BadIncludes.h:12: error:
"mozilla/Unused.h" is deprecated: Use [[nodiscard]] and (void)expr casts instead.
js/src/tests/style/BadIncludes2.h:1: error:
vanilla header includes an inline-header file "tests/style/BadIncludes2-inl.h"
js/src/tests/style/BadIncludesOrder-inl.h:5:6: error:
"vm/JSScript-inl.h" should be included after "vm/Interpreter-inl.h"
js/src/tests/style/BadIncludesOrder-inl.h:6:7: error:
"vm/Interpreter-inl.h" should be included after "js/Value.h"
js/src/tests/style/BadIncludesOrder-inl.h:7:8: error:
"js/Value.h" should be included after "ds/LifoAlloc.h"
js/src/tests/style/BadIncludesOrder-inl.h:9: error:
"jsapi.h" is deprecated: Prefer including headers from js/public.
js/src/tests/style/BadIncludesOrder-inl.h:8:9: error:
"ds/LifoAlloc.h" should be included after "jsapi.h"
js/src/tests/style/BadIncludesOrder-inl.h:9:10: error:
"jsapi.h" should be included after <stdio.h>
js/src/tests/style/BadIncludesOrder-inl.h:10:11: error:
<stdio.h> should be included after "mozilla/HashFunctions.h"
js/src/tests/style/BadIncludesOrder-inl.h:20: error:
"jsapi.h" is deprecated: Prefer including headers from js/public.
js/src/tests/style/BadIncludesOrder-inl.h:28:29: error:
"vm/JSScript.h" should be included after "vm/JSFunction.h"
(multiple files): error:
header files form one or more cycles
tests/style/HeaderCycleA1.h
-> tests/style/HeaderCycleA2.h
-> tests/style/HeaderCycleA3.h
-> tests/style/HeaderCycleA1.h
tests/style/HeaderCycleB1-inl.h
-> tests/style/HeaderCycleB2-inl.h
-> tests/style/HeaderCycleB3-inl.h
-> tests/style/HeaderCycleB4-inl.h
-> tests/style/HeaderCycleB1-inl.h
-> tests/style/jsheadercycleB5inlines.h
-> tests/style/HeaderCycleB1-inl.h
-> tests/style/HeaderCycleB4-inl.h
""".splitlines(
True
)
actual_output = []
def out(*lines):
for line in lines:
actual_output.append(line + "\n")
def error(filename, linenum, *lines):
location = filename
if linenum is not None:
location += ":" + str(linenum)
out(location + ": error:")
for line in lines:
out(" " + line)
out("")
class FileKind(object):
C = 1
CPP = 2
INL_H = 3
H = 4
TBL = 5
MSG = 6
@staticmethod
def get(filename):
if filename.endswith(".c"):
return FileKind.C
if filename.endswith(".cpp"):
return FileKind.CPP
if filename.endswith(("inlines.h", "-inl.h")):
return FileKind.INL_H
if filename.endswith(".h"):
return FileKind.H
if filename.endswith(".tbl"):
return FileKind.TBL
if filename.endswith(".msg"):
return FileKind.MSG
error(filename, None, "unknown file kind")
def check_style(enable_fixup):
# We deal with two kinds of name.
# - A "filename" is a full path to a file from the repository root.
# - An "inclname" is how a file is referred to in a #include statement.
#
# Examples (filename -> inclname)
# - "mfbt/Attributes.h" -> "mozilla/Attributes.h"
# - "mozglue/misc/TimeStamp.h -> "mozilla/TimeStamp.h"
# - "memory/mozalloc/mozalloc.h -> "mozilla/mozalloc.h"
# - "js/public/Vector.h" -> "js/Vector.h"
# - "js/src/vm/String.h" -> "vm/String.h"
non_js_dirnames = (
"mfbt/",
"memory/mozalloc/",
"mozglue/",
"intl/components/",
) # type: tuple(str)
non_js_inclnames = set() # type: set(inclname)
js_names = dict() # type: dict(filename, inclname)
# Process files in js/src.
js_src_root = os.path.join("js", "src")
for dirpath, dirnames, filenames in os.walk(js_src_root):
if dirpath == js_src_root:
# Skip any subdirectories that contain a config.status file
# (likely objdirs).
builddirs = []
for dirname in dirnames:
path = os.path.join(dirpath, dirname, "config.status")
if os.path.isfile(path):
builddirs.append(dirname)
for dirname in builddirs:
dirnames.remove(dirname)
for filename in filenames:
filepath = os.path.join(dirpath, filename).replace("\\", "/")
if not filepath.startswith(
tuple(ignored_js_src_dirs)
) and filepath.endswith((".c", ".cpp", ".h", ".tbl", ".msg")):
inclname = filepath[len("js/src/") :]
js_names[filepath] = inclname
# Look for header files in directories in non_js_dirnames.
for non_js_dir in non_js_dirnames:
for dirpath, dirnames, filenames in os.walk(non_js_dir):
for filename in filenames:
if filename.endswith(".h"):
inclname = "mozilla/" + filename
if non_js_dir == "intl/components/":
inclname = "mozilla/intl/" + filename
non_js_inclnames.add(inclname)
# Look for header files in js/public.
js_public_root = os.path.join("js", "public")
for dirpath, dirnames, filenames in os.walk(js_public_root):
for filename in filenames:
if filename.endswith((".h", ".msg")):
filepath = os.path.join(dirpath, filename).replace("\\", "/")
inclname = "js/" + filepath[len("js/public/") :]
js_names[filepath] = inclname
all_inclnames = non_js_inclnames | set(js_names.values())
edges = dict() # type: dict(inclname, set(inclname))
# We don't care what's inside the MFBT and MOZALLOC files, but because they
# are #included from JS files we have to add them to the inclusion graph.
for inclname in non_js_inclnames:
edges[inclname] = set()
# Process all the JS files.
for filename in sorted(js_names.keys()):
inclname = js_names[filename]
file_kind = FileKind.get(filename)
if (
file_kind == FileKind.C
or file_kind == FileKind.CPP
or file_kind == FileKind.H
or file_kind == FileKind.INL_H
):
included_h_inclnames = set() # type: set(inclname)
with open(filename, encoding="utf-8") as f:
code = read_file(f)
if enable_fixup:
code = code.sorted(inclname)
with open(filename, "w") as f:
f.write(code.to_source())
check_file(
filename, inclname, file_kind, code, all_inclnames, included_h_inclnames
)
edges[inclname] = included_h_inclnames
find_cycles(all_inclnames, edges)
# Compare expected and actual output.
difflines = difflib.unified_diff(
expected_output,
actual_output,
fromfile="check_spidermonkey_style.py expected output",
tofile="check_spidermonkey_style.py actual output",
)
ok = True
for diffline in difflines:
ok = False
print(diffline, end="")
return ok
def module_name(name):
"""Strip the trailing .cpp, .h, inlines.h or -inl.h from a filename."""
return (
name.replace("inlines.h", "")
.replace("-inl.h", "")
.replace(".h", "")
.replace(".cpp", "")
) # NOQA: E501
def is_module_header(enclosing_inclname, header_inclname):
"""Determine if an included name is the "module header", i.e. should be
first in the file."""
module = module_name(enclosing_inclname)
# Normal case, for example:
# module == "vm/Runtime", header_inclname == "vm/Runtime.h".
if module == module_name(header_inclname):
return True
# A public header, for example:
#
# module == "vm/CharacterEncoding",
# header_inclname == "js/CharacterEncoding.h"
#
# or (for implementation files for js/public/*/*.h headers)
#
# module == "vm/SourceHook",
# header_inclname == "js/experimental/SourceHook.h"
m = re.match(r"js\/.*?([^\/]+)\.h", header_inclname)
if m is not None and module.endswith("/" + m.group(1)):
return True
return False
class Include(object):
"""Important information for a single #include statement."""
def __init__(self, include_prefix, inclname, line_suffix, linenum, is_system):
self.include_prefix = include_prefix
self.line_suffix = line_suffix
self.inclname = inclname
self.linenum = linenum
self.is_system = is_system
def is_style_relevant(self):
# Includes are style-relevant; that is, they're checked by the pairwise
# style-checking algorithm in check_file.
return True
def section(self, enclosing_inclname):
"""Identify which section inclname belongs to.
The section numbers are as follows.
0. Module header (e.g. jsfoo.h or jsfooinlines.h within jsfoo.cpp)
1. mozilla/Foo.h
2. <foo.h> or <foo>
3. jsfoo.h, prmjtime.h, etc
4. foo/Bar.h
5. jsfooinlines.h
6. foo/Bar-inl.h
7. non-.h, e.g. *.tbl, *.msg (these can be scattered throughout files)
"""
if self.is_system:
return 2
if not self.inclname.endswith(".h"):
return 7
# A couple of modules have the .h file in js/ and the .cpp file elsewhere and so need
# special handling.
if is_module_header(enclosing_inclname, self.inclname):
return 0
if "/" in self.inclname:
if self.inclname.startswith("mozilla/"):
return 1
if self.inclname.endswith("-inl.h"):
return 6
return 4
if self.inclname.endswith("inlines.h"):
return 5
return 3
def quote(self):
if self.is_system:
return "<" + self.inclname + ">"
else:
return '"' + self.inclname + '"'
def sort_key(self, enclosing_inclname):
return (self.section(enclosing_inclname), self.inclname.lower())
def to_source(self):
return self.include_prefix + self.quote() + self.line_suffix + "\n"
class CppBlock(object):
"""C preprocessor block: a whole file or a single #if/#elif/#else block.
A #if/#endif block is the contents of a #if/#endif (or similar) section.
The top-level block, which is not within a #if/#endif pair, is also
considered a block.
Each kid is either an Include (representing a #include), OrdinaryCode, or
a nested CppBlock."""
def __init__(self, start_line=""):
self.start = start_line
self.end = ""
self.kids = []
def is_style_relevant(self):
return True
def append_ordinary_line(self, line):
if len(self.kids) == 0 or not isinstance(self.kids[-1], OrdinaryCode):
self.kids.append(OrdinaryCode())
self.kids[-1].lines.append(line)
def style_relevant_kids(self):
"""Return a list of kids in this block that are style-relevant."""
return [kid for kid in self.kids if kid.is_style_relevant()]
def sorted(self, enclosing_inclname):
"""Return a hopefully-sorted copy of this block. Implements --fixup.
When in doubt, this leaves the code unchanged.
"""
def pretty_sorted_includes(includes):
"""Return a new list containing the given includes, in order,
with blank lines separating sections."""
keys = [inc.sort_key(enclosing_inclname) for inc in includes]
if sorted(keys) == keys:
return includes # if nothing is out of order, don't touch anything
output = []
current_section = None
for (section, _), inc in sorted(zip(keys, includes)):
if current_section is not None and section != current_section:
output.append(OrdinaryCode(["\n"])) # blank line
output.append(inc)
current_section = section
return output
def should_try_to_sort(includes):
if "tests/style/BadIncludes" in enclosing_inclname:
return False # don't straighten the counterexample
if any(inc.inclname in oddly_ordered_inclnames for inc in includes):
return False # don't sort batches containing odd includes
if includes == sorted(
includes, key=lambda inc: inc.sort_key(enclosing_inclname)
):
return False # it's already sorted, avoid whitespace-only fixups
return True
# The content of the eventual output of this method.
output = []
# The current batch of includes to sort. This list only ever contains Include objects
# and whitespace OrdinaryCode objects.
batch = []
def flush_batch():
"""Sort the contents of `batch` and move it to `output`."""
assert all(
isinstance(item, Include)
or (isinstance(item, OrdinaryCode) and "".join(item.lines).isspace())
for item in batch
)
# Here we throw away the blank lines.
# `pretty_sorted_includes` puts them back.
includes = []
last_include_index = -1
for i, item in enumerate(batch):
if isinstance(item, Include):
includes.append(item)
last_include_index = i
cutoff = last_include_index + 1
if should_try_to_sort(includes):
output.extend(pretty_sorted_includes(includes) + batch[cutoff:])
else:
output.extend(batch)
del batch[:]
for kid in self.kids:
if isinstance(kid, CppBlock):
flush_batch()
output.append(kid.sorted(enclosing_inclname))
elif isinstance(kid, Include):
batch.append(kid)
else:
assert isinstance(kid, OrdinaryCode)
if kid.to_source().isspace():
batch.append(kid)
else:
flush_batch()
output.append(kid)
flush_batch()
result = CppBlock()
result.start = self.start
result.end = self.end
result.kids = output
return result
def to_source(self):
return self.start + "".join(kid.to_source() for kid in self.kids) + self.end
class OrdinaryCode(object):
"""A list of lines of code that aren't #include/#if/#else/#endif lines."""
def __init__(self, lines=None):
self.lines = lines if lines is not None else []
def is_style_relevant(self):
return False
def to_source(self):
return "".join(self.lines)
# A "snippet" is one of:
#
# * Include - representing an #include line
# * CppBlock - a whole file or #if/#elif/#else block; contains a list of snippets
# * OrdinaryCode - representing lines of non-#include-relevant code
def read_file(f):
block_stack = [CppBlock()]
# Extract the #include statements as a tree of snippets.
for linenum, line in enumerate(f, start=1):
if line.lstrip().startswith("#"):
# Look for a |#include "..."| line.
m = re.match(r'(\s*#\s*include\s+)"([^"]*)"(.*)', line)
if m is not None:
prefix, inclname, suffix = m.groups()
block_stack[-1].kids.append(
Include(prefix, inclname, suffix, linenum, is_system=False)
)
continue
# Look for a |#include <...>| line.
m = re.match(r"(\s*#\s*include\s+)<([^>]*)>(.*)", line)
if m is not None:
prefix, inclname, suffix = m.groups()
block_stack[-1].kids.append(
Include(prefix, inclname, suffix, linenum, is_system=True)
)
continue
# Look for a |#{if,ifdef,ifndef}| line.
m = re.match(r"\s*#\s*(if|ifdef|ifndef)\b", line)
if m is not None:
# Open a new block.
new_block = CppBlock(line)
block_stack[-1].kids.append(new_block)
block_stack.append(new_block)
continue
# Look for a |#{elif,else}| line.
m = re.match(r"\s*#\s*(elif|else)\b", line)
if m is not None:
# Close the current block, and open an adjacent one.
block_stack.pop()
new_block = CppBlock(line)
block_stack[-1].kids.append(new_block)
block_stack.append(new_block)
continue
# Look for a |#endif| line.
m = re.match(r"\s*#\s*endif\b", line)
if m is not None:
# Close the current block.
block_stack.pop().end = line
if len(block_stack) == 0:
raise ValueError("#endif without #if at line " + str(linenum))
continue
# Otherwise, we have an ordinary line.
block_stack[-1].append_ordinary_line(line)
if len(block_stack) > 1:
raise ValueError("unmatched #if")
return block_stack[-1]
def check_file(
filename, inclname, file_kind, code, all_inclnames, included_h_inclnames
):
def check_include_statement(include):
"""Check the style of a single #include statement."""
if include.is_system:
# Check it is not a known local file (in which case it's probably a system header).
if (
include.inclname in included_inclnames_to_ignore
or include.inclname in all_inclnames
):
error(
filename,
include.linenum,
include.quote() + " should be included using",
'the #include "..." form',
)
else:
msg = deprecated_inclnames.get(include.inclname)
if msg:
error(
filename,
include.linenum,
include.quote() + " is deprecated: " + msg,
)
if file_kind == FileKind.H or file_kind == FileKind.INL_H:
msg = deprecated_inclnames_in_header.get(include.inclname)
if msg and filename not in deprecated_inclnames_in_header_excludes:
error(
filename,
include.linenum,
include.quote() + " is deprecated: " + msg,
)
if include.inclname not in included_inclnames_to_ignore:
included_kind = FileKind.get(include.inclname)
# Check the #include path has the correct form.
if include.inclname not in all_inclnames:
error(
filename,
include.linenum,
include.quote() + " is included using the wrong path;",
"did you forget a prefix, or is the file not yet committed?",
)
# Record inclusions of .h files for cycle detection later.
# (Exclude .tbl and .msg files.)
elif included_kind == FileKind.H or included_kind == FileKind.INL_H:
included_h_inclnames.add(include.inclname)
# Check a H file doesn't #include an INL_H file.
if file_kind == FileKind.H and included_kind == FileKind.INL_H:
error(
filename,
include.linenum,
"vanilla header includes an inline-header file "
+ include.quote(),
)
# Check a file doesn't #include itself. (We do this here because the cycle
# detection below doesn't detect this case.)
if inclname == include.inclname:
error(filename, include.linenum, "the file includes itself")
def check_includes_order(include1, include2):
"""Check the ordering of two #include statements."""
if (
include1.inclname in oddly_ordered_inclnames
or include2.inclname in oddly_ordered_inclnames
):
return
section1 = include1.section(inclname)
section2 = include2.section(inclname)
if (section1 > section2) or (
(section1 == section2)
and (include1.inclname.lower() > include2.inclname.lower())
):
error(
filename,
str(include1.linenum) + ":" + str(include2.linenum),
include1.quote() + " should be included after " + include2.quote(),
)
# Check the extracted #include statements, both individually, and the ordering of
# adjacent pairs that live in the same block.
def pair_traverse(prev, this):
if isinstance(this, Include):
check_include_statement(this)
if isinstance(prev, Include):
check_includes_order(prev, this)
else:
kids = this.style_relevant_kids()
for prev2, this2 in zip([None] + kids[0:-1], kids):
pair_traverse(prev2, this2)
pair_traverse(None, code)
def find_cycles(all_inclnames, edges):
"""Find and draw any cycles."""
SCCs = tarjan(all_inclnames, edges)
# The various sorted() calls below ensure the output is deterministic.
def draw_SCC(c):
cset = set(c)
drawn = set()
def draw(v, indent):
out(" " * indent + ("-> " if indent else " ") + v)
if v in drawn:
return
drawn.add(v)
for succ in sorted(edges[v]):
if succ in cset:
draw(succ, indent + 1)
draw(sorted(c)[0], 0)
out("")
have_drawn_an_SCC = False
for scc in sorted(SCCs):
if len(scc) != 1:
if not have_drawn_an_SCC:
error("(multiple files)", None, "header files form one or more cycles")
have_drawn_an_SCC = True
draw_SCC(scc)
# Tarjan's algorithm for finding the strongly connected components (SCCs) of a graph.
def tarjan(V, E):
vertex_index = {}
vertex_lowlink = {}
index = 0
S = []
all_SCCs = []
def strongconnect(v, index):
# Set the depth index for v to the smallest unused index
vertex_index[v] = index
vertex_lowlink[v] = index
index += 1
S.append(v)
# Consider successors of v
for w in E[v]:
if w not in vertex_index:
# Successor w has not yet been visited; recurse on it
index = strongconnect(w, index)
vertex_lowlink[v] = min(vertex_lowlink[v], vertex_lowlink[w])
elif w in S:
# Successor w is in stack S and hence in the current SCC
vertex_lowlink[v] = min(vertex_lowlink[v], vertex_index[w])
# If v is a root node, pop the stack and generate an SCC
if vertex_lowlink[v] == vertex_index[v]:
i = S.index(v)
scc = S[i:]
del S[i:]
all_SCCs.append(scc)
return index
for v in V:
if v not in vertex_index:
index = strongconnect(v, index)
return all_SCCs
def main():
if sys.argv[1:] == ["--fixup"]:
# Sort #include directives in-place. Fixup mode doesn't solve
# all possible silliness that the script checks for; it's just a
# hack for the common case where renaming a header causes style
# errors.
fixup = True
elif sys.argv[1:] == []:
fixup = False
else:
print(
"TEST-UNEXPECTED-FAIL | check_spidermonkey_style.py | unexpected command "
"line options: " + repr(sys.argv[1:])
)
sys.exit(1)
ok = check_style(fixup)
if ok:
print("TEST-PASS | check_spidermonkey_style.py | ok")
else:
print(
"TEST-UNEXPECTED-FAIL | check_spidermonkey_style.py | "
+ "actual output does not match expected output; diff is above."
)
print(
"TEST-UNEXPECTED-FAIL | check_spidermonkey_style.py | "
+ "Hint: If the problem is that you renamed a header, and many #includes "
+ "are no longer in alphabetical order, commit your work and then try "
+ "`check_spidermonkey_style.py --fixup`. "
+ "You need to commit first because --fixup modifies your files in place."
)
sys.exit(0 if ok else 1)
if __name__ == "__main__":
main()