[flake8-builtins] Make strict module name comparison optional (A005) (#15951)

## Summary

This PR adds the configuration option
`lint.flake8-builtins.builtins-strict-checking`, which is used in A005
to determine whether the fully-qualified module name (relative to the
project root or source directories) should be checked instead of just
the final component as is currently the case.

As discussed in
https://github.com/astral-sh/ruff/issues/15399#issuecomment-2587017147,
the default value of the new option is `false` on preview, so modules
like `utils.logging` from the initial report are no longer flagged by
default. For non-preview the default is still strict checking.

## Test Plan

New A005 test module with the structure reported in #15399.

Fixes #15399

crates/ruff_linter/src/rules/flake8_builtins/mod.rs

@@ -12,6 +12,7 @@ mod tests {
 
     use crate::assert_messages;
     use crate::registry::Rule;
+    use crate::rules::flake8_builtins;
     use crate::settings::types::PythonVersion;
     use crate::settings::LinterSettings;
     use crate::test::{test_path, test_resource_path};
@@ -50,7 +51,13 @@ mod tests {
         let snapshot = format!("{}_{}", rule_code.noqa_code(), path.to_string_lossy());
         let diagnostics = test_path(
             Path::new("flake8_builtins").join(path).as_path(),
-            &LinterSettings::for_rule(rule_code),
+            &LinterSettings {
+                flake8_builtins: flake8_builtins::settings::Settings {
+                    builtins_strict_checking: true,
+                    ..Default::default()
+                },
+                ..LinterSettings::for_rule(rule_code)
+            },
         )?;
         assert_messages!(snapshot, diagnostics);
         Ok(())
@@ -74,7 +81,13 @@ mod tests {
         );
         let diagnostics = test_path(
             Path::new("flake8_builtins").join(path).as_path(),
-            &LinterSettings::for_rule(rule_code),
+            &LinterSettings {
+                flake8_builtins: flake8_builtins::settings::Settings {
+                    builtins_strict_checking: strict,
+                    ..Default::default()
+                },
+                ..LinterSettings::for_rule(rule_code)
+            },
         )?;
         assert_messages!(snapshot, diagnostics);
         Ok(())
@@ -92,6 +105,10 @@ mod tests {
             Path::new("flake8_builtins").join(path).as_path(),
             &LinterSettings {
                 src: vec![test_resource_path(src.join(path.parent().unwrap()))],
+                flake8_builtins: flake8_builtins::settings::Settings {
+                    builtins_strict_checking: false,
+                    ..Default::default()
+                },
                 ..LinterSettings::for_rule(rule_code)
             },
         )?;
@@ -112,6 +129,10 @@ mod tests {
             Path::new("flake8_builtins").join(path).as_path(),
             &LinterSettings {
                 project_root: test_resource_path(src.join(path.parent().unwrap())),
+                flake8_builtins: flake8_builtins::settings::Settings {
+                    builtins_strict_checking: false,
+                    ..Default::default()
+                },
                 ..LinterSettings::for_rule(rule_code)
             },
         )?;
@@ -179,6 +200,7 @@ mod tests {
             &LinterSettings {
                 flake8_builtins: super::settings::Settings {
                     builtins_allowed_modules: vec!["xml".to_string(), "logging".to_string()],
+                    builtins_strict_checking: true,
                     ..Default::default()
                 },
                 ..LinterSettings::for_rules(vec![rule_code])

crates/ruff_linter/src/rules/flake8_builtins/rules/stdlib_module_shadowing.rs

@@ -93,6 +93,11 @@ pub(crate) fn stdlib_module_shadowing(
         return None;
     }
 
+    // not allowed generally, but check for a parent in non-strict mode
+    if !settings.flake8_builtins.builtins_strict_checking && components.next().is_some() {
+        return None;
+    }
+
     Some(Diagnostic::new(
         StdlibModuleShadowing {
             name: module_name.to_string(),

crates/ruff_linter/src/rules/flake8_builtins/settings.rs

@@ -1,6 +1,6 @@
 //! Settings for the `flake8-builtins` plugin.
 
-use crate::display_settings;
+use crate::{display_settings, settings::types::PreviewMode};
 use ruff_macros::CacheKey;
 use std::fmt::{Display, Formatter};
 
@@ -8,6 +8,17 @@ use std::fmt::{Display, Formatter};
 pub struct Settings {
     pub builtins_ignorelist: Vec<String>,
     pub builtins_allowed_modules: Vec<String>,
+    pub builtins_strict_checking: bool,
+}
+
+impl Settings {
+    pub fn new(preview: PreviewMode) -> Self {
+        Self {
+            builtins_ignorelist: Vec::new(),
+            builtins_allowed_modules: Vec::new(),
+            builtins_strict_checking: preview.is_disabled(),
+        }
+    }
 }
 
 impl Display for Settings {
@@ -18,6 +29,7 @@ impl Display for Settings {
             fields = [
                 self.builtins_allowed_modules | array,
                 self.builtins_ignorelist | array,
+                self.builtins_strict_checking,
             ]
         }
         Ok(())

crates/ruff_linter/src/rules/flake8_builtins/snapshots/ruff_linter__rules__flake8_builtins__tests__A005_A005__modules__utils__logging.py_false.snap

@@ -1,4 +1,4 @@
 ---
 source: crates/ruff_linter/src/rules/flake8_builtins/mod.rs
 ---
-logging.py:1:1: A005 Module `logging` shadows a Python standard-library module
+