rome · Conaclos · May 18, 2023 · May 15, 2023 · May 15, 2023 · May 15, 2023
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -8,6 +8,9 @@
 ## Formatter
 ## Linter
 
+#### New rules
+- [`noUselessTypeConstraint`](https://docs.rome.tools/lint/rules/noUselessTypeConstraint/)
+
 #### Other changes
 
 - `noInnerDeclarations`: allow function declarations in nested block inside an _ES module_ [#4492](https://github.com/rome/tools/compare/main...Conaclos:noInnerDeclarations/4492?expand=1).
@@ -39,7 +42,6 @@
 - Fix an issue where the `noAssignInExpressions` rule replaced the operator with an invalid token, which caused other lint rules to crash. [#4464](https://github.com/rome/tools/issues/4464)
 - Fix an issue that [`noUnusedVariables`](https://docs.rome.tools/lint/rules/nounusedvariables/) rule did not correctly detect exports when a variable and an `interface` had the same name [#4468](https://github.com/rome/tools/pull/4468)
 
-
 ## 12.1.0
 
 ### CLI

diff --git a/crates/rome_diagnostics_categories/src/categories.rs b/crates/rome_diagnostics_categories/src/categories.rs
@@ -42,6 +42,7 @@ define_categories! {
     "lint/complexity/noUselessLabel":"https://docs.rome.tools/lint/rules/noUselessLabel",
     "lint/complexity/noUselessRename": "https://docs.rome.tools/lint/rules/noUselessRename",
     "lint/complexity/noUselessSwitchCase": "https://docs.rome.tools/lint/rules/noUselessSwitchCase",
+    "lint/complexity/noUselessTypeConstraint": "https://docs.rome.tools/lint/rules/noUselessTypeConstraint",
     "lint/complexity/noWith": "https://docs.rome.tools/lint/rules/noWith",
     "lint/complexity/useFlatMap": "https://docs.rome.tools/lint/rules/useFlatMap",
     "lint/complexity/useOptionalChain": "https://docs.rome.tools/lint/rules/useOptionalChain",

diff --git a/crates/rome_js_analyze/src/analyzers/complexity.rs b/crates/rome_js_analyze/src/analyzers/complexity.rs
diff --git a/crates/rome_js_analyze/src/analyzers/complexity/no_useless_type_constraint.rs b/crates/rome_js_analyze/src/analyzers/complexity/no_useless_type_constraint.rs
@@ -0,0 +1,127 @@
+use rome_analyze::context::RuleContext;
+use rome_analyze::{declare_rule, ActionCategory, Ast, Rule, RuleDiagnostic};
+use rome_console::markup;
+
+use rome_diagnostics::Applicability;
+use rome_js_syntax::TsTypeConstraintClause;
+use rome_rowan::{AstNode, BatchMutationExt};
+
+use crate::JsRuleAction;
+
+declare_rule! {
+    /// Disallow using `any` or `unknown` as type constraint.
+    ///
+    /// Generic type parameters (`<T>`) in TypeScript may be **constrained** with [`extends`](https://www.typescriptlang.org/docs/handbook/generics.html#generic-constraints).
+    /// A supplied type must then be a subtype of the supplied constraint.
+    /// All types are subtypes of `any` and `unknown`.
+    /// It is thus useless to extend from `any` or `unknown`.
+    ///
+    /// Source: https://typescript-eslint.io/rules/no-unnecessary-type-constraint/
+    ///
+    /// ## Examples
+    ///
+    /// ### Invalid
+    ///
+    /// ```ts,expect_diagnostic
+    /// interface FooAny<T extends any> {}
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// type BarAny<T extends any> = {};
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// class BazAny<T extends any> {
+    /// }
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// class BazAny {
+    ///   quxAny<U extends any>() {}
+    /// }
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// const QuuxAny = <T extends any>() => {};
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// function QuuzAny<T extends any>() {}
+    /// ```
+    ///
+    /// ```ts,expect_diagnostic
+    /// interface FooUnknown<T extends unknown> {}
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// type BarUnknown<T extends unknown> = {};
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// class BazUnknown<T extends unknown> {
+    /// }
+    /// ```ts,expect_diagnostic
+    /// class BazUnknown {
+    ///   quxUnknown<U extends unknown>() {}
+    /// }
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// const QuuxUnknown = <T extends unknown>() => {};
+    /// ```
+    /// ```ts,expect_diagnostic
+    /// function QuuzUnknown<T extends unknown>() {}
+    /// ```
+    ///
+    /// ### Valid
+    ///
+    /// ```ts
+    /// interface Foo<T> {}
+    ///
+    /// type Bar<T> = {};
+    ///```
+    pub(crate) NoUselessTypeConstraint {
+        version: "next",
+        name: "noUselessTypeConstraint",
+        recommended: true,
+    }
+}
+
+impl Rule for NoUselessTypeConstraint {
+    type Query = Ast<TsTypeConstraintClause>;
+    type State = ();
+    type Signals = Option<Self::State>;
+    type Options = ();
+
+    fn run(ctx: &RuleContext<Self>) -> Option<Self::State> {
+        let node = ctx.query();
+        let ty = node.ty().ok()?;
+
+        if ty.as_ts_any_type().is_some() || ty.as_ts_unknown_type().is_some() {
+            Some(())
+        } else {
+            None
+        }
+    }
+
+    fn diagnostic(ctx: &RuleContext<Self>, _state: &Self::State) -> Option<RuleDiagnostic> {
+        let node = ctx.query();
+        Some(
+            RuleDiagnostic::new(
+                rule_category!(),
+                node.syntax().text_trimmed_range(),
+                markup! {
+                    "Constraining a type parameter to "<Emphasis>"any"</Emphasis>" or "<Emphasis>"unknown"</Emphasis>" is useless."
+                },
+            )
+            .note(markup! {
+                "All types are subtypes of "<Emphasis>"any"</Emphasis>" and "<Emphasis>"unknown"</Emphasis>"."
+            }),
+        )
+    }
+
+    fn action(ctx: &RuleContext<Self>, _state: &Self::State) -> Option<JsRuleAction> {
+        let node = ctx.query();
+        let mut mutation = ctx.root().begin();
+        mutation.remove_node(node.clone());
+
+        Some(JsRuleAction {
+            category: ActionCategory::QuickFix,
+            applicability: Applicability::MaybeIncorrect,
+            message: markup! { "Remove the constraint." }.to_owned(),
+            mutation,
+        })
+    }
+}
diff --git a/crates/rome_js_analyze/tests/specs/complexity/noUselessTypeConstraint/invalid.ts b/crates/rome_js_analyze/tests/specs/complexity/noUselessTypeConstraint/invalid.ts
@@ -0,0 +1,15 @@
+interface FooAny1<T extends any> {
+	field: T;
+}
+
+interface FooAny2<T extends unknown> {
+	field: T;
+}
+
+class BazAny<T extends any> {
+  quxAny<U extends any>() {}
+}
+
+const QuuxAny = <T extends any>() => {};
+
+function QuuzAny<T extends any>() {}
diff --git a/crates/rome_js_analyze/tests/specs/complexity/noUselessTypeConstraint/invalid.ts.snap b/crates/rome_js_analyze/tests/specs/complexity/noUselessTypeConstraint/invalid.ts.snap
@@ -0,0 +1,149 @@
+---
+source: crates/rome_js_analyze/tests/spec_tests.rs
+assertion_line: 96
+expression: invalid.ts
+---
+# Input
+```js
+interface FooAny1<T extends any> {
+	field: T;
+}
+
+interface FooAny2<T extends unknown> {
+	field: T;
+}
+
+class BazAny<T extends any> {
+  quxAny<U extends any>() {}
+}
+
+const QuuxAny = <T extends any>() => {};
+
+function QuuzAny<T extends any>() {}
+
+```
+
+# Diagnostics
+```
+invalid.ts:1:21 lint/complexity/noUselessTypeConstraint  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  ! Constraining a type parameter to any or unknown is useless.
+
+  > 1 │ interface FooAny1<T extends any> {
+      │                     ^^^^^^^^^^^
+    2 │ 	field: T;
+    3 │ }
+
+  i All types are subtypes of any and unknown.
+
+  i Suggested fix: Remove the constraint.
+
+    1 │ interface·FooAny1<T·extends·any>·{
+      │                     -----------   
+
+```
+
+```
+invalid.ts:5:21 lint/complexity/noUselessTypeConstraint  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  ! Constraining a type parameter to any or unknown is useless.
+
+    3 │ }
+    4 │ 
+  > 5 │ interface FooAny2<T extends unknown> {
+      │                     ^^^^^^^^^^^^^^^
+    6 │ 	field: T;
+    7 │ }
+
+  i All types are subtypes of any and unknown.
+
+  i Suggested fix: Remove the constraint.
+
+    5 │ interface·FooAny2<T·extends·unknown>·{
+      │                     ---------------   
+
+```
+
+```
+invalid.ts:9:16 lint/complexity/noUselessTypeConstraint  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  ! Constraining a type parameter to any or unknown is useless.
+
+     7 │ }
+     8 │ 
+   > 9 │ class BazAny<T extends any> {
+       │                ^^^^^^^^^^^
+    10 │   quxAny<U extends any>() {}
+    11 │ }
+
+  i All types are subtypes of any and unknown.
+
+  i Suggested fix: Remove the constraint.
+
+    9 │ class·BazAny<T·extends·any>·{
+      │                -----------   
+
+```
+
+```
+invalid.ts:10:12 lint/complexity/noUselessTypeConstraint  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  ! Constraining a type parameter to any or unknown is useless.
+
+     9 │ class BazAny<T extends any> {
+  > 10 │   quxAny<U extends any>() {}
+       │            ^^^^^^^^^^^
+    11 │ }
+    12 │ 
+
+  i All types are subtypes of any and unknown.
+
+  i Suggested fix: Remove the constraint.
+
+    10 │ ··quxAny<U·extends·any>()·{}
+       │            -----------      
+
+```
+
+```
+invalid.ts:13:20 lint/complexity/noUselessTypeConstraint  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  ! Constraining a type parameter to any or unknown is useless.
+
+    11 │ }
+    12 │ 
+  > 13 │ const QuuxAny = <T extends any>() => {};
+       │                    ^^^^^^^^^^^
+    14 │ 
+    15 │ function QuuzAny<T extends any>() {}
+
+  i All types are subtypes of any and unknown.
+
+  i Suggested fix: Remove the constraint.
+
+    13 │ const·QuuxAny·=·<T·extends·any>()·=>·{};
+       │                    -----------          
+
+```
+
+```
+invalid.ts:15:20 lint/complexity/noUselessTypeConstraint  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
+
+  ! Constraining a type parameter to any or unknown is useless.
+
+    13 │ const QuuxAny = <T extends any>() => {};
+    14 │ 
+  > 15 │ function QuuzAny<T extends any>() {}
+       │                    ^^^^^^^^^^^
+    16 │ 
+
+  i All types are subtypes of any and unknown.
+
+  i Suggested fix: Remove the constraint.
+
+    15 │ function·QuuzAny<T·extends·any>()·{}
+       │                    -----------      
+
+```
+
+
diff --git a/crates/rome_js_analyze/tests/specs/complexity/noUselessTypeConstraint/valid.ts b/crates/rome_js_analyze/tests/specs/complexity/noUselessTypeConstraint/valid.ts
@@ -0,0 +1,11 @@
+interface FooAny0<T> {
+	field: T;
+}
+
+interface FooNotAny0<T extends string> {
+	field: T;
+}
+
+type Bar<T> = {};
+
+type Bar2<T extends string> = {};
diff --git a/crates/rome_js_analyze/tests/specs/complexity/noUselessTypeConstraint/valid.ts.snap b/crates/rome_js_analyze/tests/specs/complexity/noUselessTypeConstraint/valid.ts.snap
@@ -0,0 +1,21 @@
+---
+source: crates/rome_js_analyze/tests/spec_tests.rs
+expression: valid.ts
+---
+# Input
+```js
+interface FooAny0<T> {
+	field: T;
+}
+
+interface FooNotAny0<T extends string> {
+	field: T;
+}
+
+type Bar<T> = {};
+
+type Bar2<T extends string> = {};
+
+```
+
+