#10323: Fixed incorrect rule transformation rule C409 (unnecessary-li…

…teral-within-tuple-call)

crates/ruff_linter/resources/test/fixtures/flake8_comprehensions/C409.py

@@ -16,3 +16,13 @@
 tuple([  # comment
     1, 2
 ])
+
+tuple(
+    ( 
+        1,
+    )
+)
+
+t6 = tuple([1])
+t7 = tuple((1,))
+

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

@@ -1,7 +1,7 @@
 use ruff_diagnostics::{AlwaysFixableViolation, Diagnostic, Edit, Fix};
 use ruff_macros::{derive_message_formats, violation};
 use ruff_python_ast::{self as ast, Expr};
-use ruff_text_size::{Ranged, TextSize};
+use ruff_text_size::Ranged;
 
 use crate::checkers::ast::Checker;
 
@@ -71,9 +71,12 @@ pub(crate) fn unnecessary_literal_within_tuple_call(checker: &mut Checker, call:
     if !call.arguments.keywords.is_empty() {
         return;
     }
-    let Some(argument) =
-        helpers::first_argument_with_matching_function("tuple", &call.func, &call.arguments.args)
-    else {
+    let Some(argument) = helpers::exactly_one_argument_with_matching_function(
+        "tuple",
+        &call.func,
+        &call.arguments.args,
+        &call.arguments.keywords,
+    ) else {
         return;
     };
     if !checker.semantic().is_builtin("tuple") {
@@ -92,23 +95,26 @@ pub(crate) fn unnecessary_literal_within_tuple_call(checker: &mut Checker, call:
         call.range(),
     );
 
-    // Convert `tuple([1, 2])` to `tuple(1, 2)`
+    // Convert `tuple([1, 2])` to `(1, 2)`
     diagnostic.set_fix({
-        // Replace from the start of the call to the start of the inner list or tuple with `(`.
-        let call_start = Edit::replacement(
-            "(".to_string(),
-            call.start(),
-            argument.start() + TextSize::from(1),
-        );
+        let elts: Vec<Expr> = match argument {
+            Expr::List(list_expr) => list_expr.elts.clone(),
+            Expr::Tuple(tuple_expr) => tuple_expr.elts.clone(),
+            _ => return,
+        };
 
-        // Replace from the end of the inner list or tuple to the end of the call with `)`.
-        let call_end = Edit::replacement(
-            ")".to_string(),
-            argument.end() - TextSize::from(1),
-            call.end(),
-        );
+        // Replace [1, 2] -> (1, 2) or [1] -> (1,)
+        let tuple: String = if let [elt] = elts.as_slice() {
+            let elt: &str = checker.locator().slice(elt);
+            format!("({elt},)")
+        } else {
+            let elt_set: &str = checker.locator().slice(argument);
+            format!("({})", &elt_set[1..elt_set.len() - 1])
+        };
+
+        let edit = Edit::replacement(tuple, call.start(), call.end());
 
-        Fix::unsafe_edits(call_start, [call_end])
+        Fix::unsafe_edit(edit)
     });
 
     checker.diagnostics.push(diagnostic);

crates/ruff_linter/src/rules/flake8_comprehensions/snapshots/ruff_linter__rules__flake8_comprehensions__tests__C409_C409.py.snap

@@ -1,5 +1,6 @@
 ---
 source: crates/ruff_linter/src/rules/flake8_comprehensions/mod.rs
+assertion_line: 42
 ---
 C409.py:1:6: C409 [*] Unnecessary `list` literal passed to `tuple()` (rewrite as a `tuple` literal)
   |
@@ -143,6 +144,8 @@ C409.py:16:1: C409 [*] Unnecessary `list` literal passed to `tuple()` (rewrite a
 17 | |     1, 2
 18 | | ])
    | |__^ C409
+19 |   
+20 |   tuple(
    |
    = help: Rewrite as a `tuple` literal
 
@@ -155,5 +158,70 @@ C409.py:16:1: C409 [*] Unnecessary `list` literal passed to `tuple()` (rewrite a
 17 17 |     1, 2
 18    |-])
    18 |+)
+19 19 | 
+20 20 | tuple(
+21 21 |     ( 
 
+C409.py:20:1: C409 [*] Unnecessary `tuple` literal passed to `tuple()` (remove the outer call to `tuple()`)
+   |
+18 |   ])
+19 |   
+20 | / tuple(
+21 | |     ( 
+22 | |         1,
+23 | |     )
+24 | | )
+   | |_^ C409
+25 |   
+26 |   t6 = tuple([1])
+   |
+   = help: Remove outer `tuple` call
+
+ℹ Unsafe fix
+17 17 |     1, 2
+18 18 | ])
+19 19 | 
+20    |-tuple(
+21    |-    ( 
+22    |-        1,
+23    |-    )
+24    |-)
+   20 |+(1,)
+25 21 | 
+26 22 | t6 = tuple([1])
+27 23 | t7 = tuple((1,))
+
+C409.py:26:6: C409 [*] Unnecessary `list` literal passed to `tuple()` (rewrite as a `tuple` literal)
+   |
+24 | )
+25 | 
+26 | t6 = tuple([1])
+   |      ^^^^^^^^^^ C409
+27 | t7 = tuple((1,))
+   |
+   = help: Rewrite as a `tuple` literal
 
+ℹ Unsafe fix
+23 23 |     )
+24 24 | )
+25 25 | 
+26    |-t6 = tuple([1])
+   26 |+t6 = (1,)
+27 27 | t7 = tuple((1,))
+28 28 | 
+
+C409.py:27:6: C409 [*] Unnecessary `tuple` literal passed to `tuple()` (remove the outer call to `tuple()`)
+   |
+26 | t6 = tuple([1])
+27 | t7 = tuple((1,))
+   |      ^^^^^^^^^^^ C409
+   |
+   = help: Remove outer `tuple` call
+
+ℹ Unsafe fix
+24 24 | )
+25 25 | 
+26 26 | t6 = tuple([1])
+27    |-t7 = tuple((1,))
+   27 |+t7 = (1,)
+28 28 |