Replace isort and flake8 with Ruff checker (#20442)

* Replace isort and flake8 with Ruff checker

* Resolve issue with shell/api_gen.sh and correction to fix/check logic

* Resolve E721 to use `is` and `is not` for type comparisons

.devcontainer/devcontainer.json

@@ -17,9 +17,8 @@
                 ]
             },
             "extensions": [
+                "charliermarsh.ruff",
                 "ms-python.python",
-                "ms-python.isort",
-                "ms-python.flake8",
                 "ms-python.black-formatter"
             ]
         }

CONTRIBUTING.md

@@ -110,7 +110,7 @@ section of the README.
 ## Code style
 
 Keras uses [Black](https://black.readthedocs.io/en/stable/) and
-[isort](https://pycqa.github.io/isort/) to format the code. Please refer to
+[Ruff](https://docs.astral.sh/ruff/) to format the code. Please refer to
 [requirements-common.txt](https://github.com/keras-team/keras/blob/master/requirements-common.txt)
 for the required versions. Run the following command **at the root directory of
 the repo** to format your code.

keras/__init__.py

@@ -1,5 +1,3 @@
-import os
-
 # DO NOT EDIT. Generated by api_gen.sh
 from keras.api import DTypePolicy
 from keras.api import FloatDTypePolicy
@@ -54,6 +52,8 @@
 
 # END DO NOT EDIT.
 
+import os  # isort: skip
+
 # Add everything in /api/ to the module search path.
 __path__.append(os.path.join(os.path.dirname(__file__), "api"))  # noqa: F405
 

keras/src/callbacks/tensorboard.py

@@ -74,7 +74,7 @@ class TensorBoard(Callback):
             Batch-level summary writing is also available via `train_step`
             override. Please see
             [TensorBoard Scalars tutorial](
-                https://www.tensorflow.org/tensorboard/scalars_and_keras#batch-level_logging)  # noqa: E501
+                https://www.tensorflow.org/tensorboard/scalars_and_keras#batch-level_logging)
             for more details.
         profile_batch: (Not supported at this time)
             Profile the batch(es) to sample compute characteristics.
@@ -152,7 +152,7 @@ def my_summary(x):
         log_dir='./logs', profile_batch=(10,20))
     model.fit(x_train, y_train, epochs=2, callbacks=[tensorboard_callback])
     ```
-    """
+    """  # noqa: E501
 
     def __init__(
         self,

keras/src/models/functional_test.py

@@ -192,7 +192,7 @@ def test_restored_multi_output_type(self, out_type):
         x = layers.Dense(5)(inputs)
         output_a = layers.Dense(4)(x)
         output_b = layers.Dense(5)(x)
-        if dict == out_type:
+        if out_type is dict:
             outputs = {"a": output_a, "b": output_b}
         else:
             outputs = out_type([output_a, output_b])

keras/src/models/model.py

@@ -767,11 +767,11 @@ def inject_functional_model_class(cls):
     """Inject `Functional` into the hierarchy of this class if needed."""
     from keras.src.models import functional
 
-    if cls == Model:
+    if cls is Model:
         return functional.Functional
     # In case there is any multiple inheritance, we stop injecting the
     # class if keras model is not in its class hierarchy.
-    if cls == object:
+    if cls is object:
         return object
 
     cls.__bases__ = tuple(

keras/src/trainers/data_adapters/array_slicing.py

@@ -408,7 +408,7 @@ def convert_single_array(x):
         # Step 2. Normalize floats to floatx.
         def is_non_floatx_float(dtype):
             return (
-                not dtype == object
+                dtype is not object
                 and backend.is_float_dtype(dtype)
                 and not backend.standardize_dtype(dtype) == backend.floatx()
             )

keras/src/utils/sequence_utils.py

@@ -103,7 +103,7 @@ def pad_sequences(
     is_dtype_str = np.issubdtype(dtype, np.str_) or np.issubdtype(
         dtype, np.str_
     )
-    if isinstance(value, str) and dtype != object and not is_dtype_str:
+    if isinstance(value, str) and dtype is not object and not is_dtype_str:
         raise ValueError(
             f"`dtype` {dtype} is not compatible with `value`'s type: "
             f"{type(value)}\nYou should set `dtype=object` for variable length "

pyproject.toml

@@ -60,17 +60,31 @@ extend-exclude = """
 )
 """
 
-[tool.isort]
-profile = "black"
-force_single_line = "True"
-known_first_party = ["keras", "tests"]
-default_section = "THIRDPARTY"
-line_length = 80
-extend_skip_glob=[
-    "examples/*",
-    "guides/*",
+[tool.ruff]
+line-length = 80
+
+[tool.ruff.lint]
+select = [
+    "E",  # pycodestyle error
+    "F",  # Pyflakes
+    "I",  # isort
+]
+ignore = [
+    "E722",  # do not use bare 'except'
+    "E741",  # ambiguous variable name
+    "E731",  # do not assign a `lambda` expression, use a `def`
 ]
 
+[tool.ruff.lint.per-file-ignores]
+"**/__init__.py" = ["E501", "F401"]  # lines too long; imported but unused
+"**/random.py" = ["F401"]  # imported but unused
+"examples/*" = ["I", "E"]
+"guides/*" = ["I", "E", "F"]
+
+[tool.ruff.lint.isort]
+force-single-line = true
+known-first-party = ["keras"]
+
 [tool.pytest.ini_options]
 filterwarnings = [
     "error",

requirements-common.txt

@@ -1,7 +1,6 @@
 namex>=0.0.8
 black>=22
-flake8
-isort
+ruff
 pytest
 numpy
 scipy

shell/format.sh

@@ -3,9 +3,7 @@ set -Eeuo pipefail
 
 base_dir=$(dirname $(dirname $0))
 
-isort --sp "${base_dir}/pyproject.toml" .
+ruff check --exit-zero --config "${base_dir}/pyproject.toml" --fix .
 
 black --config "${base_dir}/pyproject.toml" .
 
-flake8 --config "${base_dir}/setup.cfg" .
-

shell/lint.sh

@@ -3,9 +3,7 @@ set -Eeuo pipefail
 
 base_dir=$(dirname $(dirname $0))
 
-isort --sp "${base_dir}/pyproject.toml" --check .
+ruff check --exit-zero --config "${base_dir}/pyproject.toml" .
 
 black --config "${base_dir}/pyproject.toml" --check .
 
-flake8 --config "${base_dir}/setup.cfg" .
-