Add detection for missing logging format arguments (pylint-dev#9999)

Implements the detection of too-few-args in logging format strings.
Includes new test cases and documentation updates.

doc/whatsnew/fragments/9999.false_negative.rst

@@ -0,0 +1 @@
+Add your info here

pylint/checkers/logging.py

@@ -326,12 +326,12 @@ def _check_format_string(self, node: nodes.Call, format_arg: Literal[0, 1]) -> N
           format_arg: Index of the format string in the node arguments.
         """
         num_args = _count_supplied_tokens(node.args[format_arg + 1 :])
-        if not num_args:
+        format_string = node.args[format_arg].value
+        if not num_args and "%" not in format_string:
             # If no args were supplied the string is not interpolated and can contain
             # formatting characters - it's used verbatim. Don't check any further.
             return
 
-        format_string = node.args[format_arg].value
         required_num_args = 0
         if isinstance(format_string, bytes):
             format_string = format_string.decode()

tests/functional/l/logging/logging_too_few_args_static.py

@@ -0,0 +1,7 @@
+"""Tests for logging-too-few-args when static placeholders are present."""
+
+import logging
+
+logging.error("foo %s")  # [logging-too-few-args]
+logging.info("Process %s started with ID %d")  # [logging-too-few-args]
+logging.debug("Missing args: %s %s")  # [logging-too-few-args]

tests/functional/l/logging/logging_too_few_args_static.rc

@@ -0,0 +1,2 @@
+[LOGGING]
+logging-format-style=new