[flake8-naming]: Respect import conventions (N817) (#12922)

Author: MichaReiser

crates/ruff_linter/resources/test/fixtures/pep8_naming/N817.py

@@ -1,2 +1,6 @@
 import mod.CaMel as CM
 from mod import CamelCase as CC
+
+
+# OK depending on configured import convention
+import xml.etree.ElementTree as ET

crates/ruff_linter/src/checkers/ast/analyze/statement.rs

@@ -707,11 +707,7 @@ pub(crate) fn statement(stmt: &Stmt, checker: &mut Checker) {
                     }
                     if checker.enabled(Rule::CamelcaseImportedAsAcronym) {
                         if let Some(diagnostic) = pep8_naming::rules::camelcase_imported_as_acronym(
-                            name,
-                            asname,
-                            alias,
-                            stmt,
-                            &checker.settings.pep8_naming.ignore_names,
+                            name, asname, alias, stmt, checker,
                         ) {
                             checker.diagnostics.push(diagnostic);
                         }
@@ -1026,7 +1022,7 @@ pub(crate) fn statement(stmt: &Stmt, checker: &mut Checker) {
                             asname,
                             alias,
                             stmt,
-                            &checker.settings.pep8_naming.ignore_names,
+                            checker,
                         ) {
                             checker.diagnostics.push(diagnostic);
                         }

crates/ruff_linter/src/rules/pep8_naming/mod.rs

@@ -8,11 +8,12 @@ mod tests {
     use std::path::{Path, PathBuf};
 
     use anyhow::Result;
+    use rustc_hash::FxHashMap;
     use test_case::test_case;
 
     use crate::registry::Rule;
-    use crate::rules::pep8_naming;
     use crate::rules::pep8_naming::settings::IgnoreNames;
+    use crate::rules::{flake8_import_conventions, pep8_naming};
     use crate::test::test_path;
     use crate::{assert_messages, settings};
 
@@ -87,6 +88,25 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn camelcase_imported_as_incorrect_convention() -> Result<()> {
+        let diagnostics = test_path(
+            Path::new("pep8_naming").join("N817.py").as_path(),
+            &settings::LinterSettings {
+                flake8_import_conventions: flake8_import_conventions::settings::Settings {
+                    aliases: FxHashMap::from_iter([(
+                        "xml.etree.ElementTree".to_string(),
+                        "XET".to_string(),
+                    )]),
+                    ..Default::default()
+                },
+                ..settings::LinterSettings::for_rule(Rule::CamelcaseImportedAsAcronym)
+            },
+        )?;
+        assert_messages!(diagnostics);
+        Ok(())
+    }
+
     #[test]
     fn classmethod_decorators() -> Result<()> {
         let diagnostics = test_path(

crates/ruff_linter/src/rules/pep8_naming/rules/camelcase_imported_as_acronym.rs

@@ -1,12 +1,11 @@
-use ruff_python_ast::{Alias, Stmt};
-
 use ruff_diagnostics::{Diagnostic, Violation};
 use ruff_macros::{derive_message_formats, violation};
+use ruff_python_ast::{Alias, Stmt};
 use ruff_python_stdlib::str::{self};
 use ruff_text_size::Ranged;
 
+use crate::checkers::ast::Checker;
 use crate::rules::pep8_naming::helpers;
-use crate::rules::pep8_naming::settings::IgnoreNames;
 
 /// ## What it does
 /// Checks for `CamelCase` imports that are aliased as acronyms.
@@ -23,6 +22,10 @@ use crate::rules::pep8_naming::settings::IgnoreNames;
 /// Note that this rule is distinct from `camelcase-imported-as-constant`
 /// to accommodate selective enforcement.
 ///
+/// Also note that import aliases following an import convention according to the
+/// [`lint.flake8-boolean-trap.extend-allowed-calls`] option are allowed.
+///
+///
 /// ## Example
 /// ```python
 /// from example import MyClassName as MCN
@@ -34,6 +37,9 @@ use crate::rules::pep8_naming::settings::IgnoreNames;
 /// ```
 ///
 /// [PEP 8]: https://peps.python.org/pep-0008/
+///
+/// ## Options
+/// - `lint.flake8-import-conventions.banned-aliases`
 #[violation]
 pub struct CamelcaseImportedAsAcronym {
     name: String,
@@ -54,17 +60,32 @@ pub(crate) fn camelcase_imported_as_acronym(
     asname: &str,
     alias: &Alias,
     stmt: &Stmt,
-    ignore_names: &IgnoreNames,
+    checker: &Checker,
 ) -> Option<Diagnostic> {
     if helpers::is_camelcase(name)
         && !str::is_cased_lowercase(asname)
         && str::is_cased_uppercase(asname)
         && helpers::is_acronym(name, asname)
     {
+        let ignore_names = &checker.settings.pep8_naming.ignore_names;
+
         // Ignore any explicitly-allowed names.
         if ignore_names.matches(name) || ignore_names.matches(asname) {
             return None;
         }
+
+        // Ignore names that follow a community-agreed import convention.
+        if checker
+            .settings
+            .flake8_import_conventions
+            .aliases
+            .get(&*alias.name)
+            .map(String::as_str)
+            == Some(asname)
+        {
+            return None;
+        }
+
         let mut diagnostic = Diagnostic::new(
             CamelcaseImportedAsAcronym {
                 name: name.to_string(),

crates/ruff_linter/src/rules/pep8_naming/snapshots/ruff_linter__rules__pep8_naming__tests__camelcase_imported_as_incorrect_convention.snap

@@ -0,0 +1,23 @@
+---
+source: crates/ruff_linter/src/rules/pep8_naming/mod.rs
+---
+N817.py:1:8: N817 CamelCase `CaMel` imported as acronym `CM`
+  |
+1 | import mod.CaMel as CM
+  |        ^^^^^^^^^^^^^^^ N817
+2 | from mod import CamelCase as CC
+  |
+
+N817.py:2:17: N817 CamelCase `CamelCase` imported as acronym `CC`
+  |
+1 | import mod.CaMel as CM
+2 | from mod import CamelCase as CC
+  |                 ^^^^^^^^^^^^^^^ N817
+  |
+
+N817.py:6:8: N817 CamelCase `ElementTree` imported as acronym `ET`
+  |
+5 | # OK depending on configured import convention
+6 | import xml.etree.ElementTree as ET
+  |        ^^^^^^^^^^^^^^^^^^^^^^^^^^^ N817
+  |