fix(linter/jest/no-conditional-expect): check function expression callbacks (#28055)

`jest/no-conditional-expect` now follows anonymous and named function expression callbacks to their enclosing test call, matching `eslint-plugin-jest`. Function declarations retain their existing reference-based test detection.

The shared fix also applies to Vitest. Regression cases cover async callbacks, test modifiers, `test.each`, and promise catches, alongside cases that should remain unreported.

Fixes #28054

crates/oxc_linter/src/rules/jest/no_conditional_expect.rs

@@ -305,6 +305,10 @@ fn test() {
             });",
             None,
         ),
+        ("it('foo', function () { expect(1).toBe(1); });", None),
+        ("it('foo', function callback() { expect(1).toBe(1); });", None),
+        ("const callback = function () { if (x) { expect(1).toBe(1); } };", None),
+        ("const callback = function named() { if (x) { expect(1).toBe(1); } };", None),
     ];
 
     let fail = vec![
@@ -760,6 +764,12 @@ fn test() {
             ",
             None,
         ),
+        ("it('foo', function () { if (x) { expect(1).toBe(1); } });", None),
+        ("it('foo', function callback() { if (x) { expect(1).toBe(1); } });", None),
+        ("it('foo', async function () { if (x) { expect(1).toBe(1); } });", None),
+        ("test.only('foo', function () { x && expect(1).toBe(1); });", None),
+        ("test.each([1])('foo', function () { x ? expect(1).toBe(1) : noop(); });", None),
+        ("it('foo', function () { promise.catch(function () { expect(1).toBe(1); }); });", None),
     ];
 
     Tester::new(NoConditionalExpect::NAME, NoConditionalExpect::PLUGIN, pass, fail)

crates/oxc_linter/src/rules/shared/jest_vitest/no_conditional_expect.rs

@@ -177,7 +177,7 @@ fn check_parents<'a>(
         | AstKind::LogicalExpression(_) => {
             return check_parents(parent_node, visited, InConditional(true), ctx);
         }
-        AstKind::Function(function) => {
+        AstKind::Function(function) if function.is_declaration() => {
             let Some(ident) = &function.id else {
                 return InConditional(false);
             };

crates/oxc_linter/src/rules/vitest/no_conditional_expect.rs

@@ -305,6 +305,10 @@ fn test() {
             });",
             None,
         ),
+        ("it('foo', function () { expect(1).toBe(1); });", None),
+        ("it('foo', function callback() { expect(1).toBe(1); });", None),
+        ("const callback = function () { if (x) { expect(1).toBe(1); } };", None),
+        ("const callback = function named() { if (x) { expect(1).toBe(1); } };", None),
     ];
 
     let mut fail = vec![
@@ -760,6 +764,12 @@ fn test() {
             ",
             None,
         ),
+        ("it('foo', function () { if (x) { expect(1).toBe(1); } });", None),
+        ("it('foo', function callback() { if (x) { expect(1).toBe(1); } });", None),
+        ("it('foo', async function () { if (x) { expect(1).toBe(1); } });", None),
+        ("test.only('foo', function () { x && expect(1).toBe(1); });", None),
+        ("test.each([1])('foo', function () { x ? expect(1).toBe(1) : noop(); });", None),
+        ("it('foo', function () { promise.catch(function () { expect(1).toBe(1); }); });", None),
     ];
 
     let pass_vitest = vec![

crates/oxc_linter/src/snapshots/jest_no_conditional_expect.snap

@@ -415,3 +415,45 @@ source: crates/oxc_linter/src/tester.rs
  8 │                     }
    ╰────
   help: Avoid calling `expect` conditionally
+
+  ⚠ jest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:34]
+ 1 │ it('foo', function () { if (x) { expect(1).toBe(1); } });
+   ·                                  ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ jest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:42]
+ 1 │ it('foo', function callback() { if (x) { expect(1).toBe(1); } });
+   ·                                          ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ jest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:40]
+ 1 │ it('foo', async function () { if (x) { expect(1).toBe(1); } });
+   ·                                        ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ jest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:37]
+ 1 │ test.only('foo', function () { x && expect(1).toBe(1); });
+   ·                                     ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ jest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:41]
+ 1 │ test.each([1])('foo', function () { x ? expect(1).toBe(1) : noop(); });
+   ·                                         ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ jest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:53]
+ 1 │ it('foo', function () { promise.catch(function () { expect(1).toBe(1); }); });
+   ·                                                     ──────
+   ╰────
+  help: Avoid calling `expect` conditionally

crates/oxc_linter/src/snapshots/vitest_no_conditional_expect.snap

@@ -416,6 +416,48 @@ source: crates/oxc_linter/src/tester.rs
    ╰────
   help: Avoid calling `expect` conditionally
 
+  ⚠ vitest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:34]
+ 1 │ it('foo', function () { if (x) { expect(1).toBe(1); } });
+   ·                                  ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ vitest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:42]
+ 1 │ it('foo', function callback() { if (x) { expect(1).toBe(1); } });
+   ·                                          ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ vitest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:40]
+ 1 │ it('foo', async function () { if (x) { expect(1).toBe(1); } });
+   ·                                        ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ vitest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:37]
+ 1 │ test.only('foo', function () { x && expect(1).toBe(1); });
+   ·                                     ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ vitest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:41]
+ 1 │ test.each([1])('foo', function () { x ? expect(1).toBe(1) : noop(); });
+   ·                                         ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
+  ⚠ vitest(no-conditional-expect): Unexpected conditional expect
+   ╭─[no_conditional_expect.tsx:1:53]
+ 1 │ it('foo', function () { promise.catch(function () { expect(1).toBe(1); }); });
+   ·                                                     ──────
+   ╰────
+  help: Avoid calling `expect` conditionally
+
   ⚠ vitest(no-conditional-expect): Unexpected conditional expect
    ╭─[no_conditional_expect.tsx:3:30]
  2 │             it('foo', () => {