document lazy logging codemod

integration_tests/test_lazy_logging.py

@@ -0,0 +1,34 @@
+from core_codemods.lazy_logging import LazyLogging
+from integration_tests.base_test import (
+    BaseIntegrationTest,
+    original_and_expected_from_code_path,
+)
+
+
+class TestLazyLogging(BaseIntegrationTest):
+    codemod = LazyLogging
+    code_path = "tests/samples/lazy_logging.py"
+    original_code, expected_new_code = original_and_expected_from_code_path(
+        code_path,
+        [
+            (2, """logging.error("Error occurred: %s", e)\n"""),
+            (3, """logging.error("Error occurred: %s", e)\n"""),
+        ],
+    )
+
+    # fmt: off
+    expected_diff =(
+    """--- \n"""
+    """+++ \n"""
+    """@@ -1,4 +1,4 @@\n"""
+    """ import logging\n"""
+    """ e = "Some error"\n"""
+    """-logging.error("Error occurred: %s" % e)\n"""
+    """-logging.error("Error occurred: " + e)\n"""
+    """+logging.error("Error occurred: %s", e)\n"""
+    """+logging.error("Error occurred: %s", e)\n""")
+    # fmt: on
+
+    expected_line_change = "3"
+    change_description = LazyLogging.change_description
+    num_changes = 2

src/codemodder/scripts/generate_docs.py

@@ -222,6 +222,10 @@ class DocMetadata:
         importance="Medium",
         guidance_explained="An `assert` statement on a non-empty tuple is likely unintended and should be rewritten. However, the new change may result in assertion failures that should be reviewed.",
     ),
+    "lazy-logging": DocMetadata(
+        importance="Medium",
+        guidance_explained="We believe this change is safe and will not cause any issues.",
+    ),
 }
 
 METADATA = CORE_METADATA | {

src/core_codemods/__init__.py

@@ -49,8 +49,8 @@
 from .fix_empty_sequence_comparison import FixEmptySequenceComparison
 from .remove_assertion_in_pytest_raises import RemoveAssertionInPytestRaises
 from .fix_assert_tuple import FixAssertTuple
-
 from .sonar.sonar_numpy_nan_equality import SonarNumpyNanEquality
+from .lazy_logging import LazyLogging
 
 registry = CodemodCollection(
     origin="pixee",
@@ -106,6 +106,7 @@
         FixEmptySequenceComparison,
         RemoveAssertionInPytestRaises,
         FixAssertTuple,
+        LazyLogging,
     ],
 )
 

src/core_codemods/docs/pixee_python_lazy-logging.md

@@ -0,0 +1,13 @@
+This codemod converts "eager" logging into "lazy" logging, which is preferred for performance efficiency and resource optimization.
+Lazy logging defers the actual construction and formatting of log messages until it's confirmed that the message will be logged based on the current log level, thereby avoiding unnecessary computation and memory usage for messages that will be ignored. 
+
+Our changes look something like this:
+
+```diff
+import logging
+e = "Some error"
+- logging.error("Error occurred: %s" % e)
+- logging.error("Error occurred: " + e)
++ logging.error("Error occurred: %s", e)
++ logging.error("Error occurred: %s", e)
+```

src/core_codemods/lazy_logging.py

@@ -8,7 +8,7 @@
 class LazyLogging(SimpleCodemod, NameAndAncestorResolutionMixin):
     metadata = Metadata(
         name="lazy-logging",
-        summary="Simplify Boolean Expressions Using `startswith` and `endswith`",
+        summary="Convert Eager Logging to Lazy Logging",
         review_guidance=ReviewGuidance.MERGE_WITHOUT_REVIEW,
         references=[],
     )

tests/samples/lazy_logging.py

@@ -0,0 +1,4 @@
+import logging
+e = "Some error"
+logging.error("Error occurred: %s" % e)
+logging.error("Error occurred: " + e)