[flake8-comprehensions] Unnecessary list comprehension (rewrite as a set comprehension) (C403) - Handle extraneous parentheses around list comprehension

crates/ruff_linter/resources/test/fixtures/flake8_comprehensions/C403.py

@@ -21,3 +21,14 @@ def f(x):
 s = set([  # comment
     x for x in range(3)
 ])
+
+s = set(([x for x in range(3)]))
+
+s = set(((([x for x in range(3)]))))
+
+s = set( # outer set comment
+( # inner paren comment - not preserved
+((
+[ # comprehension comment
+ x for x in range(3)]
+ ))))

crates/ruff_linter/src/rules/flake8_comprehensions/rules/unnecessary_list_comprehension_set.rs

@@ -1,6 +1,7 @@
 use ruff_diagnostics::{AlwaysFixableViolation, Diagnostic, Edit, Fix};
 use ruff_macros::{derive_message_formats, ViolationMetadata};
 use ruff_python_ast as ast;
+use ruff_python_ast::parenthesize::parenthesized_range;
 use ruff_text_size::{Ranged, TextSize};
 
 use crate::checkers::ast::Checker;
@@ -55,32 +56,39 @@ pub(crate) fn unnecessary_list_comprehension_set(checker: &mut Checker, call: &a
     if !checker.semantic().has_builtin_binding("set") {
         return;
     }
-    if argument.is_list_comp_expr() {
-        let diagnostic = Diagnostic::new(UnnecessaryListComprehensionSet, call.range());
-        let fix = {
-            // Replace `set(` with `{`.
-            let call_start = Edit::replacement(
-                pad_start("{", call.range(), checker.locator(), checker.semantic()),
-                call.start(),
-                call.arguments.start() + TextSize::from(1),
-            );
+    if !argument.is_list_comp_expr() {
+        return;
+    }
+    let diagnostic = Diagnostic::new(UnnecessaryListComprehensionSet, call.range());
+    let one = TextSize::from(1);
 
-            // Replace `)` with `}`.
-            let call_end = Edit::replacement(
-                pad_end("}", call.range(), checker.locator(), checker.semantic()),
-                call.arguments.end() - TextSize::from(1),
-                call.end(),
-            );
+    // Replace `set(` with `{`.
+    let call_start = Edit::replacement(
+        pad_start("{", call.range(), checker.locator(), checker.semantic()),
+        call.start(),
+        call.arguments.start() + one,
+    );
 
-            // Delete the open bracket (`[`).
-            let argument_start =
-                Edit::deletion(argument.start(), argument.start() + TextSize::from(1));
+    // Replace `)` with `}`.
+    let call_end = Edit::replacement(
+        pad_end("}", call.range(), checker.locator(), checker.semantic()),
+        call.arguments.end() - one,
+        call.end(),
+    );
 
-            // Delete the close bracket (`]`).
-            let argument_end = Edit::deletion(argument.end() - TextSize::from(1), argument.end());
+    // If the list comprehension is parenthesized, remove the parentheses in addition to
+    // removing the brackets.
+    let replacement_range = parenthesized_range(
+        argument.into(),
+        (&call.arguments).into(),
+        checker.comment_ranges(),
+        checker.locator().contents(),
+    )
+    .unwrap_or_else(|| argument.range());
 
-            Fix::unsafe_edits(call_start, [argument_start, argument_end, call_end])
-        };
-        checker.diagnostics.push(diagnostic.with_fix(fix));
-    }
+    let span = argument.range().add_start(one).sub_end(one);
+    let replacement =
+        Edit::range_replacement(checker.source()[span].to_string(), replacement_range);
+    let fix = Fix::unsafe_edits(call_start, [call_end, replacement]);
+    checker.diagnostics.push(diagnostic.with_fix(fix));
 }

crates/ruff_linter/src/rules/flake8_comprehensions/snapshots/ruff_linter__rules__flake8_comprehensions__tests__C403_C403.py.snap

@@ -220,6 +220,8 @@ C403.py:21:5: C403 [*] Unnecessary list comprehension (rewrite as a set comprehe
 22 | |     x for x in range(3)
 23 | | ])
    | |__^ C403
+24 |
+25 |   s = set(([x for x in range(3)]))
    |
    = help: Rewrite as a set comprehension
 
@@ -232,3 +234,77 @@ C403.py:21:5: C403 [*] Unnecessary list comprehension (rewrite as a set comprehe
 22 22 |     x for x in range(3)
 23    |-])
    23 |+}
+24 24 | 
+25 25 | s = set(([x for x in range(3)]))
+26 26 | 
+
+C403.py:25:5: C403 [*] Unnecessary list comprehension (rewrite as a set comprehension)
+   |
+23 | ])
+24 |
+25 | s = set(([x for x in range(3)]))
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C403
+26 |
+27 | s = set(((([x for x in range(3)]))))
+   |
+   = help: Rewrite as a set comprehension
+
+ℹ Unsafe fix
+22 22 |     x for x in range(3)
+23 23 | ])
+24 24 | 
+25    |-s = set(([x for x in range(3)]))
+   25 |+s = {x for x in range(3)}
+26 26 | 
+27 27 | s = set(((([x for x in range(3)]))))
+28 28 | 
+
+C403.py:27:5: C403 [*] Unnecessary list comprehension (rewrite as a set comprehension)
+   |
+25 | s = set(([x for x in range(3)]))
+26 |
+27 | s = set(((([x for x in range(3)]))))
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ C403
+28 |
+29 | s = set( # outer set comment
+   |
+   = help: Rewrite as a set comprehension
+
+ℹ Unsafe fix
+24 24 | 
+25 25 | s = set(([x for x in range(3)]))
+26 26 | 
+27    |-s = set(((([x for x in range(3)]))))
+   27 |+s = {x for x in range(3)}
+28 28 | 
+29 29 | s = set( # outer set comment
+30 30 | ( # inner paren comment - not preserved
+
+C403.py:29:5: C403 [*] Unnecessary list comprehension (rewrite as a set comprehension)
+   |
+27 |   s = set(((([x for x in range(3)]))))
+28 |
+29 |   s = set( # outer set comment
+   |  _____^
+30 | | ( # inner paren comment - not preserved
+31 | | ((
+32 | | [ # comprehension comment
+33 | |  x for x in range(3)]
+34 | |  ))))
+   | |_____^ C403
+   |
+   = help: Rewrite as a set comprehension
+
+ℹ Unsafe fix
+26 26 | 
+27 27 | s = set(((([x for x in range(3)]))))
+28 28 | 
+29    |-s = set( # outer set comment
+30    |-( # inner paren comment - not preserved
+31    |-((
+32    |-[ # comprehension comment
+33    |- x for x in range(3)]
+34    |- ))))
+   29 |+s = { # outer set comment
+   30 |+ # comprehension comment
+   31 |+ x for x in range(3)}