Add PERF to lint and fix findings (#9510)

Tests/test_bmp_reference.py

@@ -56,7 +56,7 @@ def test_questionable() -> None:
                 im.load()
             if os.path.basename(f) not in supported:
                 print(f"Please add {f} to the partially supported bmp specs.")
-        except Exception:  # as msg:
+        except Exception:  # noqa: PERF203
             if os.path.basename(f) in supported:
                 raise
 
@@ -106,7 +106,7 @@ def test_good() -> None:
 
                     assert_image_similar(im_converted, compare_converted, 5)
 
-        except Exception as msg:
+        except Exception as msg:  # noqa: PERF203
             # there are three here that are unsupported:
             unsupported = (
                 os.path.join(base, "g", "rgb32bf.bmp"),

Tests/test_file_container.py

@@ -179,9 +179,7 @@ def test_iter(bytesmode: bool) -> None:
         container = ContainerIO.ContainerIO(fh, 0, 120)
 
         # Act
-        data = []
-        for line in container:
-            data.append(line)
+        data = list(container)
 
         # Assert
         if bytesmode:

Tests/test_file_libtiff.py

@@ -224,10 +224,7 @@ class TestFileLibTiff(LibTiffTestCase):
         with Image.open("Tests/images/hopper_g4.tif") as im:
             assert isinstance(im, TiffImagePlugin.TiffImageFile)
             for tag in im.tag_v2:
-                try:
-                    del core_items[tag]
-                except KeyError:
-                    pass
+                core_items.pop(tag, None)
             del core_items[320]  # colormap is special, tested below
 
             # Type codes:

pyproject.toml

@@ -146,6 +146,7 @@ lint.select = [
   "I",      # isort
   "ISC",    # flake8-implicit-str-concat
   "LOG",    # flake8-logging
+  "PERF",   # perflint
   "PGH",    # pygrep-hooks
   "PIE",    # flake8-pie
   "PT",     # flake8-pytest-style

setup.py

@@ -302,7 +302,7 @@ def _pkg_config(name: str) -> tuple[list[str], list[str]] | None:
                 subprocess.check_output(command_cflags).decode("utf8").strip(),
             )[::2][1:]
             return libs, cflags
-        except Exception:
+        except Exception:  # noqa: PERF203
             pass
     return None
 
@@ -1078,10 +1078,10 @@ libraries: list[tuple[str, _BuildInfo]] = [
 ]
 
 files: list[str | os.PathLike[str]] = ["src/_imaging.c"]
-for src_file in _IMAGING:
-    files.append("src/" + src_file + ".c")
-for src_file in _LIB_IMAGING:
-    files.append(os.path.join("src/libImaging", src_file + ".c"))
+files.extend("src/" + src_file + ".c" for src_file in _IMAGING)
+files.extend(
+    os.path.join("src/libImaging", src_file + ".c") for src_file in _LIB_IMAGING
+)
 ext_modules = [
     Extension("PIL._imaging", files),
     Extension("PIL._imagingft", ["src/_imagingft.c"]),

src/PIL/GifImagePlugin.py

@@ -164,13 +164,13 @@ class GifImageFile(ImageFile.ImageFile):
             self._seek(0)
 
         last_frame = self.__frame
-        for f in range(self.__frame + 1, frame + 1):
-            try:
+        try:
+            for f in range(self.__frame + 1, frame + 1):
                 self._seek(f)
-            except EOFError as e:
-                self.seek(last_frame)
-                msg = "no more images in GIF file"
-                raise EOFError(msg) from e
+        except EOFError as e:
+            self.seek(last_frame)
+            msg = "no more images in GIF file"
+            raise EOFError(msg) from e
 
     def _seek(self, frame: int, update_image: bool = True) -> None:
         if isinstance(self._fp, DeferredError):

src/PIL/IcnsImagePlugin.py

@@ -80,8 +80,7 @@ def read_32(
                 if byte_int & 0x80:
                     blocksize = byte_int - 125
                     byte = fobj.read(1)
-                    for i in range(blocksize):
-                        data.append(byte)
+                    data.extend([byte] * blocksize)
                 else:
                     blocksize = byte_int + 1
                     data.append(fobj.read(blocksize))

src/PIL/Image.py

@@ -488,7 +488,7 @@ def init() -> bool:
         try:
             logger.debug("Importing %s", plugin)
             __import__(f"{__spec__.parent}.{plugin}", globals(), locals(), [])
-        except ImportError as e:
+        except ImportError as e:  # noqa: PERF203
             logger.debug("Image: failed to import %s: %s", plugin, e)
 
     if OPEN or SAVE:

src/PIL/ImageDraw.py

@@ -597,9 +597,7 @@ class ImageDraw:
                 mode = self.fontmode
                 if stroke_width == 0 and embedded_color:
                     mode = "RGBA"
-                coord = []
-                for i in range(2):
-                    coord.append(int(xy[i]))
+                coord = [int(xy[i]) for i in range(2)]
                 start = (math.modf(xy[0])[0], math.modf(xy[1])[0])
                 try:
                     mask, offset = image_text.font.getmask2(  # type: ignore[union-attr,misc]

src/PIL/ImageFile.py

@@ -215,8 +215,10 @@ class ImageFile(Image.Image):
             if subifd_offsets:
                 if not isinstance(subifd_offsets, tuple):
                     subifd_offsets = (subifd_offsets,)
-                for subifd_offset in subifd_offsets:
-                    ifds.append((exif._get_ifd_dict(subifd_offset), subifd_offset))
+                ifds = [
+                    (exif._get_ifd_dict(subifd_offset), subifd_offset)
+                    for subifd_offset in subifd_offsets
+                ]
         ifd1 = exif.get_ifd(ExifTags.IFD.IFD1)
         if ifd1 and ifd1.get(ExifTags.Base.JpegIFOffset):
             assert exif._info is not None

src/PIL/ImageFont.py

@@ -930,7 +930,7 @@ def load_path(filename: str | bytes) -> ImageFont:
     for directory in sys.path:
         try:
             return load(os.path.join(directory, filename))
-        except OSError:
+        except OSError:  # noqa: PERF203
             pass
     msg = f'cannot find font file "{filename}" in sys.path'
     if os.path.exists(filename):

src/PIL/ImagePalette.py

@@ -198,13 +198,11 @@ class ImagePalette:
         try:
             fp.write("# Palette\n")
             fp.write(f"# Mode: {self.mode}\n")
+            palette_len = len(self.palette)
             for i in range(256):
                 fp.write(f"{i}")
                 for j in range(i * len(self.mode), (i + 1) * len(self.mode)):
-                    try:
-                        fp.write(f" {self.palette[j]}")
-                    except IndexError:
-                        fp.write(" 0")
+                    fp.write(f" {self.palette[j] if j < palette_len else 0}")
                 fp.write("\n")
         finally:
             if open_fp:

src/PIL/IptcImagePlugin.py

@@ -185,13 +185,9 @@ def getiptcinfo(
 
     data = None
 
-    info: dict[tuple[int, int], bytes | list[bytes]] = {}
     if isinstance(im, IptcImageFile):
         # return info dictionary right away
-        for k, v in im.info.items():
-            if isinstance(k, tuple):
-                info[k] = v
-        return info
+        return {k: v for k, v in im.info.items() if isinstance(k, tuple)}
 
     elif isinstance(im, JpegImagePlugin.JpegImageFile):
         # extract the IPTC/NAA resource
@@ -227,7 +223,4 @@ def getiptcinfo(
     except (IndexError, KeyError):
         pass  # expected failure
 
-    for k, v in iptc_im.info.items():
-        if isinstance(k, tuple):
-            info[k] = v
-    return info
+    return {k: v for k, v in iptc_im.info.items() if isinstance(k, tuple)}

src/PIL/JpegImagePlugin.py

@@ -127,8 +127,8 @@ def APP(self: JpegImageFile, marker: int) -> None:
         # parse the image resource block
         offset = 14
         photoshop = self.info.setdefault("photoshop", {})
-        while s[offset : offset + 4] == b"8BIM":
-            try:
+        try:
+            while s[offset : offset + 4] == b"8BIM":
                 offset += 4
                 # resource code
                 code = i16(s, offset)
@@ -153,8 +153,8 @@ def APP(self: JpegImageFile, marker: int) -> None:
                     photoshop[code] = data
                 offset += size
                 offset += offset & 1  # align
-            except struct.error:
-                break  # insufficient data
+        except struct.error:
+            pass  # insufficient data
 
     elif marker == 0xFFEE and s.startswith(b"Adobe"):
         self.info["adobe"] = i16(s, 5)
@@ -738,17 +738,15 @@ def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
             if not (0 < len(qtables) < 5):
                 msg = "None or too many quantization tables"
                 raise ValueError(msg)
-            for idx, table in enumerate(qtables):
-                try:
+            try:
+                for idx, table in enumerate(qtables):
                     if len(table) != 64:
                         msg = "Invalid quantization table"
                         raise TypeError(msg)
-                    table_array = array.array("H", table)
-                except TypeError as e:
-                    msg = "Invalid quantization table"
-                    raise ValueError(msg) from e
-                else:
-                    qtables[idx] = list(table_array)
+                    qtables[idx] = list(array.array("H", table))
+            except TypeError as e:
+                msg = "Invalid quantization table"
+                raise ValueError(msg) from e
             return qtables
 
     if qtables == "keep":

src/PIL/PcfFontFile.py

@@ -251,7 +251,7 @@ class PcfFontFile(FontFile.FontFile):
                 ]
                 if encoding_offset != 0xFFFF:
                     encoding[i] = encoding_offset
-            except UnicodeDecodeError:
+            except UnicodeDecodeError:  # noqa: PERF203
                 # character is not supported in selected encoding
                 pass
 

src/PIL/PngImagePlugin.py

@@ -866,13 +866,13 @@ class PngImageFile(ImageFile.ImageFile):
             self._seek(0, True)
 
         last_frame = self.__frame
-        for f in range(self.__frame + 1, frame + 1):
-            try:
+        try:
+            for f in range(self.__frame + 1, frame + 1):
                 self._seek(f)
-            except EOFError as e:
-                self.seek(last_frame)
-                msg = "no more images in APNG file"
-                raise EOFError(msg) from e
+        except EOFError as e:
+            self.seek(last_frame)
+            msg = "no more images in APNG file"
+            raise EOFError(msg) from e
 
     def _seek(self, frame: int, rewind: bool = False) -> None:
         assert self.png is not None

winbuild/build_prepare.py

@@ -542,14 +542,11 @@ def write_script(
 
 
 def get_footer(dep: dict[str, Any]) -> list[str]:
-    lines = []
-    for out in dep.get("headers", []):
-        lines.append(cmd_copy(out, "{inc_dir}"))
-    for out in dep.get("libs", []):
-        lines.append(cmd_copy(out, "{lib_dir}"))
-    for out in dep.get("bins", []):
-        lines.append(cmd_copy(out, "{bin_dir}"))
-    return lines
+    return (
+        [cmd_copy(out, "{inc_dir}") for out in dep.get("headers", [])]
+        + [cmd_copy(out, "{lib_dir}") for out in dep.get("libs", [])]
+        + [cmd_copy(out, "{bin_dir}") for out in dep.get("bins", [])]
+    )
 
 
 def build_env(prefs: dict[str, str], verbose: bool) -> None: