feat: Add refurb linter

.lintrunner.toml

@@ -267,28 +267,54 @@ init_command = [
 ]
 
 [[linter]]
- code = 'PYUPGRADE'
- is_formatter = true
- include_patterns = [
-     'lintrunner_adapters/**/*.py',
-     'lintrunner_adapters/**/*.pyi',
- ]
- exclude_patterns = []
- command = [
-     'python',
-     '-m',
-     'lintrunner_adapters',
-     'run',
-     'pyupgrade_linter',
-     '--py37-plus',
-     '@{{PATHSFILE}}'
- ]
- init_command = [
-     'python',
-     '-m',
-     'lintrunner_adapters',
-     'run',
-     'pip_init',
-     '--dry-run={{DRYRUN}}',
-     'pyupgrade==3.3.1',
- ]
+code = 'PYUPGRADE'
+is_formatter = true
+include_patterns = [
+    'lintrunner_adapters/**/*.py',
+    'lintrunner_adapters/**/*.pyi',
+]
+exclude_patterns = []
+command = [
+    'python',
+    '-m',
+    'lintrunner_adapters',
+    'run',
+    'pyupgrade_linter',
+    '--py37-plus',
+    '@{{PATHSFILE}}'
+]
+init_command = [
+    'python',
+    '-m',
+    'lintrunner_adapters',
+    'run',
+    'pip_init',
+    '--dry-run={{DRYRUN}}',
+    'pyupgrade==3.3.1',
+]
+
+[[linter]]
+code = 'REFURB'
+include_patterns = [
+    'lintrunner_adapters/**/*.py',
+    'lintrunner_adapters/**/*.pyi',
+]
+exclude_patterns = []
+command = [
+    'python',
+    '-m',
+    'lintrunner_adapters',
+    'run',
+    'refurb_linter',
+    '--',
+    '@{{PATHSFILE}}'
+]
+init_command = [
+    'python',
+    '-m',
+    'lintrunner_adapters',
+    'run',
+    'pip_init',
+    '--dry-run={{DRYRUN}}',
+    'refurb==1.10.0;python_version>="3.10"',
+]

examples/adapters/refurb/.lintrunner.toml

@@ -0,0 +1,28 @@
+[[linter]]
+code = 'REFURB'
+include_patterns = [
+    '**/*.py',
+]
+exclude_patterns = []
+command = [
+    'python',
+    '-m',
+    'lintrunner_adapters',
+    'run',
+    'refurb_linter',
+    '--config-file=pyproject.toml',
+    '--show-disable',
+    '--severity=FURB101:advice',
+    '--severity=FURB102:warning',
+    '--',
+    '@{{PATHSFILE}}'
+]
+init_command = [
+    'python',
+    '-m',
+    'lintrunner_adapters',
+    'run',
+    'pip_init',
+    '--dry-run={{DRYRUN}}',
+    'refurb==1.10.0',
+]

lintrunner_adapters/adapters/flake8_linter.py

@@ -134,7 +134,7 @@ def get_issue_severity(code: str) -> LintSeverity:
     # "T49": internal type checker errors or unmatched messages
     if any(
         code.startswith(x)
-        for x in [
+        for x in (
             "B9",
             "C4",
             "C9",
@@ -143,13 +143,13 @@ def get_issue_severity(code: str) -> LintSeverity:
             "E5",
             "T400",
             "T49",
-        ]
+        )
     ):
         return LintSeverity.ADVICE
 
     # "F821": Undefined name
     # "E999": syntax error
-    if any(code.startswith(x) for x in ["F821", "E999"]):
+    if any(code.startswith(x) for x in ("F821", "E999")):
         return LintSeverity.ERROR
 
     # "F": PyFlakes Error

lintrunner_adapters/adapters/newlines_linter.py

@@ -21,11 +21,11 @@ def check_file(filename: str) -> LintMessage | None:
     with open(filename, "rb") as f:
         lines = f.readlines()
 
-    if len(lines) == 0:
+    if not lines:
         # File is empty, just leave it alone.
         return None
 
-    if len(lines) == 1 and len(lines[0]) == 1:
+    if len(lines) == len(lines[0]) == 1:
         # file is wrong whether or not the only byte is a newline
         return LintMessage(
             path=filename,
@@ -77,7 +77,7 @@ def check_file(filename: str) -> LintMessage | None:
     for idx, line in enumerate(lines):
         if len(line) >= 2 and line[-1] == NEWLINE and line[-2] == CARRIAGE_RETURN:
             if not has_changes:
-                original_lines = list(lines)
+                original_lines = lines.copy()
                 has_changes = True
             lines[idx] = line[:-2] + b"\n"
 

lintrunner_adapters/adapters/refurb_linter.py

@@ -0,0 +1,167 @@
+"""Refurbish and modernize Python code"""
+
+from __future__ import annotations
+
+import argparse
+import logging
+import re
+import sys
+import textwrap
+
+from lintrunner_adapters import LintMessage, LintSeverity, add_default_options
+from lintrunner_adapters._common.lintrunner_common import run_command
+
+LINTER_CODE = "REFURB"
+
+RESULTS_RE = re.compile(
+    r"""(?mx)
+        ^
+        (?P<file>.*?):
+        (?P<line>\d+):
+        (?:(?P<column>-?\d+))?
+        (?:\s\[(?P<code>.*)\]:)?
+        \s(?P<message>.*)
+        $
+        """
+)
+
+
+def _test_results_re() -> None:
+    """Doctests.
+
+    >>> def t(s): return RESULTS_RE.search(s).groupdict()
+
+    >>> t(r"main.py:3:17 [FURB109]: Use `in (x, y, z)` instead of `in [x, y, z]`")
+    ... # doctest: +NORMALIZE_WHITESPACE
+    {'file': 'main.py', 'line': '3', 'column': '17', 'code': 'FURB109',
+     'message': 'Use `in (x, y, z)` instead of `in [x, y, z]`'}
+
+    >>> t(r"main.py:4:5 [FURB101]: Use `y = Path(x).read_text()` instead of `with open(x, ...) as f: y = f.read()`")
+    ... # doctest: +NORMALIZE_WHITESPACE
+    {'file': 'main.py', 'line': '4', 'column': '5', 'code': 'FURB101',
+     'message': 'Use `y = Path(x).read_text()` instead of `with open(x, ...) as f: y = f.read()`'}
+    """
+    pass
+
+
+def format_lint_message(message: str, code: str, show_disable: bool) -> str:
+    formatted = f"{message}"
+    if show_disable:
+        formatted += textwrap.dedent(
+            f"""
+
+            To disable, use
+            [tool.refurb]
+            ignore = [{code}]
+            or
+            disable = [{code}]
+            """
+        )
+    return formatted
+
+
+def check_files(
+    filenames: list[str],
+    severities: dict[str, LintSeverity],
+    *,
+    config_file: str,
+    retries: int,
+    show_disable: bool,
+) -> list[LintMessage]:
+    try:
+        proc = run_command(
+            [sys.executable, "-mrefurb", "--config-file", config_file] + filenames,
+            retries=retries,
+        )
+    except OSError as err:
+        return [
+            LintMessage(
+                path=None,
+                line=None,
+                char=None,
+                code=LINTER_CODE,
+                severity=LintSeverity.ERROR,
+                name="command-failed",
+                original=None,
+                replacement=None,
+                description=(f"Failed due to {err.__class__.__name__}:\n{err}"),
+            )
+        ]
+    stdout = str(proc.stdout, "utf-8").strip()
+    return [
+        LintMessage(
+            path=match["file"],
+            name=match["code"] or "note",
+            description=format_lint_message(
+                match["message"],
+                match["code"],
+                show_disable,
+            ),
+            line=int(match["line"]),
+            char=int(match["column"])
+            if match["column"] is not None and not match["column"].startswith("-")
+            else None,
+            code=LINTER_CODE,
+            severity=severities.get(match["code"], LintSeverity.ADVICE),
+            original=None,
+            replacement=None,
+        )
+        for match in RESULTS_RE.finditer(stdout)
+    ]
+
+
+def main() -> None:
+    parser = argparse.ArgumentParser(
+        description=f"refurb wrapper linter. Linter code: {LINTER_CODE}. "
+        f"Use pyproject.toml to configure any refurb settings.",
+        fromfile_prefix_chars="@",
+    )
+    parser.add_argument(
+        "--config-file",
+        default="pyproject.toml",
+        help="path to pyproject.toml config file",
+    )
+    parser.add_argument(
+        "--severity",
+        action="append",
+        help="map code to severity (e.g. `FURB109:advice`). "
+        "This option can be used multiple times.",
+    )
+    parser.add_argument(
+        "--show-disable",
+        action="store_true",
+        help="show how to disable a lint message",
+    )
+    add_default_options(parser)
+    args = parser.parse_args()
+
+    logging.basicConfig(
+        format="<%(threadName)s:%(levelname)s> %(message)s",
+        level=logging.NOTSET
+        if args.verbose
+        else logging.DEBUG
+        if len(args.filenames) < 1000
+        else logging.INFO,
+        stream=sys.stderr,
+    )
+
+    severities: dict[str, LintSeverity] = {}
+    if args.severity:
+        for severity in args.severity:
+            parts = severity.split(":", 1)
+            assert len(parts) == 2, f"invalid severity `{severity}`"
+            severities[parts[0]] = LintSeverity(parts[1])
+
+    lint_messages = check_files(
+        args.filenames,
+        severities,
+        config_file=args.config_file,
+        retries=args.retries,
+        show_disable=args.show_disable,
+    )
+    for lint_message in lint_messages:
+        lint_message.display()
+
+
+if __name__ == "__main__":
+    main()

pyproject.toml

@@ -73,3 +73,7 @@ disable = [
     "unused-argument",
     "unused-import",
 ]
+
+[tool.refurb]
+python_version = "3.7"
+disable = ["FURB101", "FURB150"] # disable suggestions using pathlib

requirements-test.txt

@@ -1,4 +1,5 @@
 # Test dependencies to avoid doctest import errors
 add-trailing-comma==2.4.0
 pyupgrade==3.3.1
+refurb==1.10.0;python_version>="3.10"
 ufmt==2.0.1