Files
carbon-lang/scripts/source_stats.py
T
Chandler Carruth b79ce84f33 Switch to uv for all of our Python scripts (#7242)
This removes the need to install any specific version of Python or
figure out how to configure it by instead asking users to install `uv`
and letting it manage Python. Among other advantages, `uv` is designed
to be fast enough to embed directly into our scripts.

We were already using this in `bench_runner.py` so that the script could
import non standard library dependencies. Moving to it for the rest of
our Python unifies the approach and will also enable dependencies
whenever needed.

I've left `github_tools` alone as it has special handling with its own
Bazel setup.

I've updated the contributing tools to explain the approach here.
2026-05-28 18:03:52 +00:00

314 lines
11 KiB
Python
Executable File

#!/usr/bin/env -S uv run --script
# /// script
# requires-python = ">=3.11"
# ///
"""Script to compute statistics about source code."""
from __future__ import annotations
__copyright__ = """
Part of the Carbon Language project, under the Apache License v2.0 with LLVM
Exceptions. See /LICENSE for license information.
SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
"""
import argparse
from alive_progress import alive_bar # type: ignore
import math
from multiprocessing import Pool
import re
import termplotlib as tpl # type: ignore
from pathlib import Path
from typing import Optional
from dataclasses import dataclass, field, asdict
from collections import Counter
BLANK_RE = re.compile(r"\s*")
COMMENT_RE = re.compile(r"\s*///*\s*")
LINE_RE = re.compile(
r"""
(?P<class_intro>\b(class|struct)\s+(?P<class_name>\w+)\b)|
(?P<end_open_curly>{\s*(?P<open_curly_trailing_comment>//.*)?)|
(?P<trailing_comment>//.*)|
(?P<internal_comment>/\*.*\*/)|
(?P<string_literal>"([^"]|\\")*"|'([^']|\\')*')|
(?P<float_literal>\b(0[xb][0-9a-fA-F']*|[0-9][0-9']*)\.[0-9a-fA-F']*([eEpP][0-9a-fA-F']*)?)|
(?P<int_literal>\b(0[xb][0-9a-fA-F']+|[0-9][0-9']*)([eEpP][0-9a-fA-F']*)?)|
(?P<symbol>[\[\]{}(),.;]|[-+=!@#$%^&*/?|<>]+)|
(?P<keyword>\b(auto|bool|break|case|catch|char|class|const|continue|default|do|double|else|enum|explicit|extern|false|float|for|friend|goto|if|inline|int|long|mutable|namespace|new|nullptr|operator|private|protected|public|return|short|signed|sizeof|static|struct|switch|template|this|throw|true|try|typedef|union|unsigned|using|virtual|void|while)\b)|
(?P<id>\b\w+\b)
""",
re.X,
)
@dataclass
class Stats:
"""Stats collected while scanning source files"""
lines: int = 0
blank_lines: int = 0
comment_lines: int = 0
empty_comment_lines: int = 0
comment_line_widths: Counter[int] = field(default_factory=lambda: Counter())
lines_with_trailing_comments: int = 0
classes: int = 0
internal_comments: int = 0
string_literals: int = 0
string_literals_per_line: Counter[int] = field(
default_factory=lambda: Counter()
)
int_literals: int = 0
int_literals_per_line: Counter[int] = field(
default_factory=lambda: Counter()
)
float_literals: int = 0
float_literals_per_line: Counter[int] = field(
default_factory=lambda: Counter()
)
symbols: int = 0
symbols_per_line: Counter[int] = field(default_factory=lambda: Counter())
keywords: int = 0
keywords_per_line: Counter[int] = field(default_factory=lambda: Counter())
identifiers: int = 0
identifier_widths: Counter[int] = field(default_factory=lambda: Counter())
ids_per_line: Counter[int] = field(default_factory=lambda: Counter())
unique_ids_per_ten_lines: Counter[int] = field(
default_factory=lambda: Counter()
)
def accumulate(self, other: Stats) -> None:
self.lines += other.lines
self.blank_lines += other.blank_lines
self.empty_comment_lines += other.empty_comment_lines
self.comment_lines += other.comment_lines
self.comment_line_widths.update(other.comment_line_widths)
self.lines_with_trailing_comments += other.lines_with_trailing_comments
self.classes += other.classes
self.internal_comments += other.internal_comments
self.string_literals += other.string_literals
self.string_literals_per_line.update(other.string_literals_per_line)
self.int_literals += other.int_literals
self.int_literals_per_line.update(other.int_literals_per_line)
self.float_literals += other.float_literals
self.float_literals_per_line.update(other.float_literals_per_line)
self.symbols += other.symbols
self.symbols_per_line.update(other.symbols_per_line)
self.keywords += other.keywords
self.keywords_per_line.update(other.keywords_per_line)
self.identifiers += other.identifiers
self.identifier_widths.update(other.identifier_widths)
self.ids_per_line.update(other.ids_per_line)
self.unique_ids_per_ten_lines.update(other.unique_ids_per_ten_lines)
def scan_file(file: Path) -> Stats:
"""Scans the provided file and accumulates stats."""
stats = Stats()
unique_ids = set()
for line in file.open():
# Strip off the line endings.
line = line.rstrip("\r\n")
# Skip over super long lines that are often URLs or structured data that
# doesn't match "normal" source code patterns.
if len(line) > 80:
continue
stats.lines += 1
if re.fullmatch(BLANK_RE, line):
stats.blank_lines += 1
continue
if m := re.match(COMMENT_RE, line):
stats.comment_lines += 1
if m.end() == len(line):
stats.empty_comment_lines += 1
else:
stats.comment_line_widths[len(line)] += 1
continue
line_string_literals = 0
line_int_literals = 0
line_float_literals = 0
line_symbols = 0
line_keywords = 0
line_identifiers = 0
for m in re.finditer(LINE_RE, line):
if m.group("trailing_comment"):
stats.lines_with_trailing_comments += 1
break
if m.group("class_intro"):
stats.classes += 1
line_keywords += 1
line_identifiers += 1
stats.identifier_widths[len(m.group("class_name"))] += 1
elif m.group("end_open_curly"):
line_symbols += 1
elif m.group("internal_comment"):
stats.internal_comments += 1
elif m.group("string_literal"):
line_string_literals += 1
elif m.group("int_literal"):
line_int_literals += 1
elif m.group("float_literal"):
line_float_literals += 1
elif m.group("symbol"):
line_symbols += 1
elif m.group("keyword"):
line_keywords += 1
else:
assert m.group("id"), "Line is '%s', and match is '%s'" % (
line,
line[m.start() : m.end()],
)
line_identifiers += 1
stats.identifier_widths[len(m.group("id"))] += 1
unique_ids.add(m.group("id"))
stats.string_literals += line_string_literals
stats.string_literals_per_line[line_string_literals] += 1
stats.int_literals += line_int_literals
stats.int_literals_per_line[line_int_literals] += 1
stats.float_literals += line_float_literals
stats.float_literals_per_line[line_float_literals] += 1
stats.symbols += line_symbols
stats.symbols_per_line[line_symbols] += 1
stats.keywords += line_keywords
stats.keywords_per_line[line_keywords] += 1
stats.identifiers += line_identifiers
stats.ids_per_line[line_identifiers] += 1
if stats.lines > 0:
stats.unique_ids_per_ten_lines[
math.ceil((len(unique_ids) * 10) / stats.lines)
] += 1
return stats
def parse_args(args: Optional[list[str]] = None) -> argparse.Namespace:
"""Parsers command-line arguments and flags."""
parser = argparse.ArgumentParser(description=__doc__)
parser.add_argument(
"files",
metavar="FILE",
type=Path,
nargs="+",
help="A file to scan while collecting statistics.",
)
return parser.parse_args(args=args)
def main() -> None:
parsed_args = parse_args()
stats = Stats()
with alive_bar(len(parsed_args.files)) as bar:
with Pool() as p:
for file_stats in p.imap_unordered(scan_file, parsed_args.files):
stats.accumulate(file_stats)
bar()
print("""
## Stats ##
Lines: %(lines)d
Blank lines: %(blank_lines)d
Comment lines: %(comment_lines)d
Empty comment lines: %(empty_comment_lines)d
Lines with trailing comments: %(lines_with_trailing_comments)d
Classes: %(classes)d
Internal comments: %(internal_comments)d
String literals: %(string_literals)d
Int literals: %(int_literals)d
Float literals: %(float_literals)d
Symbols: %(symbols)d
Keywords: %(keywords)d
IDs: %(identifiers)d""" % asdict(stats))
tokens = (
stats.string_literals
+ stats.int_literals
+ stats.float_literals
+ stats.symbols
+ stats.keywords
+ stats.identifiers
)
print(f"""
Fraction of blank lines: {stats.blank_lines / stats.lines}
Fraction of comment lines: {stats.comment_lines / stats.lines}
Total counted tokens: {tokens}
Fraction string literals: {stats.string_literals / tokens}
Fraction int literals: {stats.int_literals / tokens}
Fraction float literals: {stats.float_literals / tokens}
Fraction symbols: {stats.symbols / tokens}
Fraction keywords: {stats.keywords / tokens}
Fraction IDs: {stats.identifiers / tokens}
""")
def print_histogram(
title: str, data: dict[int, int], column_format: str
) -> None:
print()
key_min = min(data.keys())
key_max = max(data.keys()) + 1
values = [data.get(k, 0) for k in range(key_min, key_max)]
keys = [column_format % k for k in range(key_min, key_max)]
total = sum(values)
median = key_min
p90 = key_min
p95 = key_min
p99 = key_min
count = total
for k in range(key_min, key_max):
count -= data.get(k, 0)
if median == key_min and count <= total / 2:
median = k
if p90 == key_min and count <= total / 10:
p90 = k
if p95 == key_min and count <= total / 20:
p95 = k
if p99 == key_min and count <= total / 100:
p99 = k
print(
title + f" (median: {median}, p90: {p90}, p95: {p95}, p99: {p99})"
)
fig = tpl.figure()
fig.barh(values, keys)
fig.show()
print_histogram(
"## Comment line widths ##", stats.comment_line_widths, "%d columns"
)
print_histogram(
"## String literals per line ##",
stats.string_literals_per_line,
"%d literals",
)
print_histogram(
"## Int literals per line ##",
stats.int_literals_per_line,
"%d literals",
)
print_histogram(
"## Float literals per line ##",
stats.float_literals_per_line,
"%d literals",
)
print_histogram(
"## Symbols per line ##", stats.symbols_per_line, "%d symbols"
)
print_histogram(
"## Keywords per line ##", stats.keywords_per_line, "%d keywords"
)
print_histogram("## ID widths ##", stats.identifier_widths, "%d characters")
print_histogram("## IDs per line ##", stats.ids_per_line, "%d ids")
print_histogram(
"## Unique IDs per 10 lines ##",
stats.unique_ids_per_ten_lines,
"%d ids",
)
if __name__ == "__main__":
main()