feat(linter/eslint-plugin-vitest): implement no-conditional-tests (#4955)

crates/oxc_linter/src/rules.rs

@@ -452,6 +452,7 @@ mod promise {
 }
 
 mod vitest {
+    pub mod no_conditional_tests;
     pub mod no_import_node_test;
     pub mod prefer_to_be_falsy;
     pub mod prefer_to_be_truthy;
@@ -866,4 +867,5 @@ oxc_macros::declare_all_lint_rules! {
     vitest::no_import_node_test,
     vitest::prefer_to_be_falsy,
     vitest::prefer_to_be_truthy,
+    vitest::no_conditional_tests,
 }

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

@@ -0,0 +1,139 @@
+use oxc_ast::AstKind;
+use oxc_diagnostics::OxcDiagnostic;
+use oxc_macros::declare_oxc_lint;
+use oxc_span::Span;
+
+use crate::{
+    context::LintContext,
+    rule::Rule,
+    utils::{
+        collect_possible_jest_call_node, is_type_of_jest_fn_call, JestFnKind, JestGeneralFnKind,
+        PossibleJestNode,
+    },
+};
+
+fn no_conditional_tests(span0: Span) -> OxcDiagnostic {
+    OxcDiagnostic::warn("Avoid having conditionals in tests")
+        .with_help("Remove the surrounding if statement.")
+        .with_label(span0)
+}
+
+#[derive(Debug, Default, Clone)]
+pub struct NoConditionalTests;
+
+declare_oxc_lint!(
+    /// ### What it does
+    /// The rule disallows the use of conditional statements within test cases to ensure that tests are deterministic and clearly readable.
+    ///
+    /// ### Examples
+    ///
+    /// Examples of **incorrect** code for this rule:
+    /// ```js
+    /// describe('my tests', () => {
+    ///     if (true) {
+    ///         it('is awesome', () => {
+    ///             doTheThing()
+    ///         })
+    ///     }
+    /// })
+    /// ```
+    ///
+    /// Examples of **correct** code for this rule:
+    /// ```js
+    /// describe('my tests', () => {
+    ///     it('is awesome', () => {
+    ///         doTheThing()
+    ///     })
+    /// })
+    /// ```
+    NoConditionalTests,
+    correctness,
+);
+
+impl Rule for NoConditionalTests {
+    fn run_once(&self, ctx: &LintContext) {
+        for node in &collect_possible_jest_call_node(ctx) {
+            run(node, ctx);
+        }
+    }
+}
+
+fn run<'a>(possible_jest_node: &PossibleJestNode<'a, '_>, ctx: &LintContext<'a>) {
+    let node = possible_jest_node.node;
+    if let AstKind::CallExpression(call_expr) = node.kind() {
+        if is_type_of_jest_fn_call(
+            call_expr,
+            possible_jest_node,
+            ctx,
+            &[
+                JestFnKind::General(JestGeneralFnKind::Describe),
+                JestFnKind::General(JestGeneralFnKind::Test),
+            ],
+        ) {
+            let if_statement_node = ctx
+                .nodes()
+                .iter_parents(node.id())
+                .find(|node| matches!(node.kind(), AstKind::IfStatement(_)));
+
+            let Some(node) = if_statement_node else { return };
+
+            if let AstKind::IfStatement(if_statement) = node.kind() {
+                ctx.diagnostic(no_conditional_tests(if_statement.span));
+            }
+        }
+    }
+}
+
+#[test]
+fn test() {
+    use crate::tester::Tester;
+
+    let pass = vec![
+        r#"test("shows error", () => {});"#,
+        r#"it("foo", function () {})"#,
+        "it('foo', () => {}); function myTest() { if ('bar') {} }",
+        r#"function myFunc(str: string) {
+			    return str;
+			  }
+			  describe("myTest", () => {
+			     it("convert shortened equal filter", () => {
+			      expect(
+			      myFunc("5")
+			      ).toEqual("5");
+			     });
+			    });"#,
+        r#"describe("shows error", () => {
+			     if (1 === 2) {
+			      myFunc();
+			     }
+			     expect(true).toBe(false);
+			    });"#,
+    ];
+
+    let fail = vec![
+        r#"describe("shows error", () => {
+			    if(true) {
+			     test("shows error", () => {
+			      expect(true).toBe(true);
+			     })
+			    }
+			   })"#,
+        r#"
+			   describe("shows error", () => {
+			    if(true) {
+			     it("shows error", () => {
+			      expect(true).toBe(true);
+			      })
+			     }
+			   })"#,
+        r#"describe("errors", () => {
+			    if (Math.random() > 0) {
+			     test("test2", () => {
+			     expect(true).toBeTruthy();
+			    });
+			    }
+			   });"#,
+    ];
+
+    Tester::new(NoConditionalTests::NAME, pass, fail).test_and_snapshot();
+}

crates/oxc_linter/src/snapshots/no_conditional_tests.snap

@@ -0,0 +1,38 @@
+---
+source: crates/oxc_linter/src/tester.rs
+---
+  ⚠ eslint-plugin-vitest(no-conditional-tests): Avoid having conditionals in tests
+   ╭─[no_conditional_tests.tsx:2:8]
+ 1 │     describe("shows error", () => {
+ 2 │ ╭─▶                 if(true) {
+ 3 │ │                    test("shows error", () => {
+ 4 │ │                     expect(true).toBe(true);
+ 5 │ │                    })
+ 6 │ ╰─▶                 }
+ 7 │                    })
+   ╰────
+  help: Remove the surrounding if statement.
+
+  ⚠ eslint-plugin-vitest(no-conditional-tests): Avoid having conditionals in tests
+   ╭─[no_conditional_tests.tsx:3:8]
+ 2 │                    describe("shows error", () => {
+ 3 │ ╭─▶                 if(true) {
+ 4 │ │                    it("shows error", () => {
+ 5 │ │                     expect(true).toBe(true);
+ 6 │ │                     })
+ 7 │ ╰─▶                  }
+ 8 │                    })
+   ╰────
+  help: Remove the surrounding if statement.
+
+  ⚠ eslint-plugin-vitest(no-conditional-tests): Avoid having conditionals in tests
+   ╭─[no_conditional_tests.tsx:2:8]
+ 1 │     describe("errors", () => {
+ 2 │ ╭─▶                 if (Math.random() > 0) {
+ 3 │ │                    test("test2", () => {
+ 4 │ │                    expect(true).toBeTruthy();
+ 5 │ │                   });
+ 6 │ ╰─▶                 }
+ 7 │                    });
+   ╰────
+  help: Remove the surrounding if statement.