Implement pylint E1519 singledispatch-method #970

crates/ruff_linter/resources/test/fixtures/pylint/E1519.py

@@ -0,0 +1,8 @@
+from functools import singledispatch
+
+
+class Board:
+    @singledispatch  # [singledispatch-method]
+    @classmethod
+    def convert_position(cls, position):
+        pass

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

@@ -40,6 +40,7 @@ pub(crate) fn deferred_scopes(checker: &mut Checker) {
         Rule::UnusedPrivateTypedDict,
         Rule::UnusedStaticMethodArgument,
         Rule::UnusedVariable,
+        Rule::SingleDispatchMethod,
     ]) {
         return;
     }
@@ -389,6 +390,10 @@ pub(crate) fn deferred_scopes(checker: &mut Checker) {
             if checker.enabled(Rule::TooManyLocals) {
                 pylint::rules::too_many_locals(checker, scope, &mut diagnostics);
             }
+
+            if checker.enabled(Rule::SingleDispatchMethod) {
+                pylint::rules::single_dispatch_method(checker, scope_id, &mut diagnostics);
+            }
         }
     }
     checker.diagnostics.extend(diagnostics);

crates/ruff_linter/src/codes.rs

@@ -252,6 +252,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Pylint, "E1307") => (RuleGroup::Stable, rules::pylint::rules::BadStringFormatType),
         (Pylint, "E1310") => (RuleGroup::Stable, rules::pylint::rules::BadStrStripCall),
         (Pylint, "E1507") => (RuleGroup::Stable, rules::pylint::rules::InvalidEnvvarValue),
+        (Pylint, "E1519") => (RuleGroup::Preview, rules::pylint::rules::SingleDispatchMethod),
         (Pylint, "E1700") => (RuleGroup::Stable, rules::pylint::rules::YieldFromInAsyncFunction),
         (Pylint, "E2502") => (RuleGroup::Stable, rules::pylint::rules::BidirectionalUnicode),
         (Pylint, "E2510") => (RuleGroup::Stable, rules::pylint::rules::InvalidCharacterBackspace),

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

@@ -20,6 +20,7 @@ mod tests {
     use crate::settings::LinterSettings;
     use crate::test::test_path;
 
+    #[test_case(Rule::SingleDispatchMethod, Path::new("E1519.py"))]
     #[test_case(Rule::AssertOnStringLiteral, Path::new("assert_on_string_literal.py"))]
     #[test_case(Rule::AwaitOutsideAsync, Path::new("await_outside_async.py"))]
     #[test_case(Rule::BadOpenMode, Path::new("bad_open_mode.py"))]

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

@@ -53,6 +53,7 @@ pub(crate) use repeated_isinstance_calls::*;
 pub(crate) use repeated_keyword_argument::*;
 pub(crate) use return_in_init::*;
 pub(crate) use self_assigning_variable::*;
+pub(crate) use single_dispatch_method::*;
 pub(crate) use single_string_slots::*;
 pub(crate) use subprocess_popen_preexec_fn::*;
 pub(crate) use subprocess_run_without_check::*;
@@ -139,6 +140,7 @@ mod repeated_isinstance_calls;
 mod repeated_keyword_argument;
 mod return_in_init;
 mod self_assigning_variable;
+mod single_dispatch_method;
 mod single_string_slots;
 mod subprocess_popen_preexec_fn;
 mod subprocess_run_without_check;

crates/ruff_linter/src/rules/pylint/rules/single_dispatch_method.rs

@@ -0,0 +1,22 @@
+use ruff_diagnostics::{Diagnostic, FixAvailability, Violation};
+use ruff_macros::{derive_message_formats, violation};
+use ruff_python_semantic::ScopeId;
+
+use ruff_source_file::SourceRow;
+
+use crate::checkers::ast::Checker;
+
+#[violation]
+pub struct SingleDispatchMethod {}
+
+impl Violation for SingleDispatchMethod {
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::None;
+
+    #[derive_message_formats]
+    fn message(&self) -> String {
+        format!("")
+    }
+}
+
+/// E1519
+pub(crate) fn single_dispatch_method(checker: &Checker, diagnostics: &mut Vec<Diagnostic>) {}