feat: added flake8

pyproject.toml

@@ -281,6 +281,50 @@ partial_branches = [
 # Note: Vulture uses command-line args, but we can document settings here
 # vulture --min-confidence 80 --exclude ".venv,Bash" .
 
+# ============================================================================
+# FLAKE8 - Python linter (via Flake8-pyproject for pyproject.toml support)
+# ============================================================================
+[tool.flake8]
+# Maximum line length (matches ruff/black)
+max-line-length = 88
+# Maximum McCabe complexity (matches ruff C901 threshold)
+max-complexity = 10
+# Maximum cognitive complexity (flake8-cognitive-complexity)
+max-cognitive-complexity = 12
+# Maximum function length (flake8-functions)
+max-function-length = 50
+# Maximum returns/arguments per function
+max-returns = 6
+max-arguments = 5
+# Docstring convention (matches ruff)
+docstring-convention = "google"
+# Select all error codes
+select = ["E", "F", "W", "C", "B", "B950"]
+# Extend with plugin codes
+extend-select = ["B", "B9", "C4", "SIM", "PT", "TC", "ANN"]
+# Ignore rules that conflict with ruff-format or are duplicated
+extend-ignore = [
+    "E501",   # Line too long - B950 from bugbear is smarter (allows 10% overflow)
+    "W503",   # Line break before binary operator - contradicts PEP 8 update
+    "ANN101", # Missing type annotation for self
+    "ANN102", # Missing type annotation for cls
+]
+# Exclude directories
+exclude = [
+    ".git",
+    ".venv",
+    "__pycache__",
+    "build",
+    "dist",
+    ".eggs",
+    "Bash/ffmpeg-build",
+]
+# Per-file ignores
+per-file-ignores = [
+    "**/tests/**/*.py:S101,ANN",
+    "**/test_*.py:S101,ANN",
+]
+
 # ============================================================================
 # PYDOCSTYLE - Docstring style checker (ruff handles this, but for standalone)
 # ============================================================================

python_pkg/brother_printer/check_brother_printer.py

@@ -13,6 +13,7 @@ Usage:
 
 from __future__ import annotations
 
+import contextlib
 from dataclasses import dataclass, field
 import fcntl
 import logging
@@ -243,11 +244,9 @@ def _drain_buffer(fd: int) -> None:
     """Read and discard any stale data from the USB buffer."""
     flags = fcntl.fcntl(fd, fcntl.F_GETFL)
     fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)
-    try:
+    with contextlib.suppress(OSError):
         while os.read(fd, 4096):
             pass
-    except (BlockingIOError, OSError):
-        pass
     fcntl.fcntl(fd, fcntl.F_SETFL, flags & ~os.O_NONBLOCK)
 
 
@@ -274,15 +273,13 @@ def pjl_query(fd: int, cmd: str, timeout_sec: float = 5.0) -> str:
         if readable:
             # Switch to non-blocking to read all available data
             fcntl.fcntl(fd, fcntl.F_SETFL, flags | os.O_NONBLOCK)
-            try:
+            with contextlib.suppress(OSError):
                 while True:
                     chunk = os.read(fd, 4096)
                     if chunk:
                         response += chunk
                     else:
                         break
-            except (BlockingIOError, OSError):
-                pass
             fcntl.fcntl(fd, fcntl.F_SETFL, flags & ~os.O_NONBLOCK)
             # If we got meaningful PJL data, stop waiting
             if response and (b"=" in response or b"@PJL" in response):