fix(60908): Unexpected "'Type' is declared but its value is never read." error with jsdoc @import syntax

src/compiler/binder.ts

@@ -176,6 +176,7 @@ import {
     isInTopLevelContext,
     isJSDocConstructSignature,
     isJSDocEnumTag,
+    isJSDocImportTag,
     isJSDocTemplateTag,
     isJSDocTypeAlias,
     isJSDocTypeAssertion,
@@ -1108,6 +1109,9 @@ function createBinder(): (file: SourceFile, options: CompilerOptions) => void {
             if (canHaveFlowNode(node) && node.flowNode) {
                 node.flowNode = undefined;
             }
+            if (isJSDocImportTag(node)) {
+                return;
+            }
             bindEachChild(node);
             bindJSDoc(node);
             inAssignmentPattern = saveInAssignmentPattern;

tests/baselines/reference/importTag23.symbols

@@ -0,0 +1,25 @@
+//// [tests/cases/conformance/jsdoc/importTag23.ts] ////
+
+=== types.d.ts ===
+export type T = {
+>T : Symbol(T, Decl(types.d.ts, 0, 0))
+
+    a: number;
+>a : Symbol(a, Decl(types.d.ts, 0, 17))
+
+};
+
+=== foo.js ===
+/** @import { T } from "./types.d.ts" */
+
+export default async function f() {
+>f : Symbol(f, Decl(foo.js, 0, 0))
+
+	/** @type {T[]} */
+	const types = [];
+>types : Symbol(types, Decl(foo.js, 4, 6))
+
+	return types;
+>types : Symbol(types, Decl(foo.js, 4, 6))
+}
+

tests/baselines/reference/importTag23.types

@@ -0,0 +1,32 @@
+//// [tests/cases/conformance/jsdoc/importTag23.ts] ////
+
+=== types.d.ts ===
+export type T = {
+>T : T
+>  : ^
+
+    a: number;
+>a : number
+>  : ^^^^^^
+
+};
+
+=== foo.js ===
+/** @import { T } from "./types.d.ts" */
+
+export default async function f() {
+>f : () => Promise<T[]>
+>  : ^^^^^^^^^^^^^^^^^^
+
+	/** @type {T[]} */
+	const types = [];
+>types : T[]
+>      : ^^^
+>[] : undefined[]
+>   : ^^^^^^^^^^^
+
+	return types;
+>types : T[]
+>      : ^^^
+}
+

tests/baselines/reference/importTag24.errors.txt

@@ -0,0 +1,38 @@
+a.js(3,10): error TS6133: 'f1' is declared but its value is never read.
+a.js(11,10): error TS6133: 'f3' is declared but its value is never read.
+a.js(19,10): error TS6133: 'f4' is declared but its value is never read.
+a.js(19,17): error TS2322: Type 'number' is not assignable to type 'string'.
+
+
+==== types.d.ts (0 errors) ====
+    export type Foo = string;
+
+==== a.js (4 errors) ====
+    /** @import { Foo } from './types.d.ts') */
+
+    function f1() { return undefined; }
+             ~~
+!!! error TS6133: 'f1' is declared but its value is never read.
+
+    export function f2() {
+        /** @type {Set<Foo>} */
+        const foo = new Set([ 'a', 'b' ]);
+        return foo;
+    }
+
+    function f3() { return undefined; }
+             ~~
+!!! error TS6133: 'f3' is declared but its value is never read.
+
+    /** @type {Set<Foo>} */
+    export const foo = new Set([ 'a', 'b' ]);
+
+    /**
+     * @returns {Foo}
+     */
+    function f4() { return 1; }
+             ~~
+!!! error TS6133: 'f4' is declared but its value is never read.
+                    ~~~~~~
+!!! error TS2322: Type 'number' is not assignable to type 'string'.
+

tests/baselines/reference/importTag24.symbols

@@ -0,0 +1,40 @@
+//// [tests/cases/conformance/jsdoc/importTag24.ts] ////
+
+=== types.d.ts ===
+export type Foo = string;
+>Foo : Symbol(Foo, Decl(types.d.ts, 0, 0))
+
+=== a.js ===
+/** @import { Foo } from './types.d.ts') */
+
+function f1() { return undefined; }
+>f1 : Symbol(f1, Decl(a.js, 0, 0))
+>undefined : Symbol(undefined)
+
+export function f2() {
+>f2 : Symbol(f2, Decl(a.js, 2, 35))
+
+    /** @type {Set<Foo>} */
+    const foo = new Set([ 'a', 'b' ]);
+>foo : Symbol(foo, Decl(a.js, 6, 9))
+>Set : Symbol(Set, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --), Decl(lib.esnext.collection.d.ts, --, --))
+
+    return foo;
+>foo : Symbol(foo, Decl(a.js, 6, 9))
+}
+
+function f3() { return undefined; }
+>f3 : Symbol(f3, Decl(a.js, 8, 1))
+>undefined : Symbol(undefined)
+
+/** @type {Set<Foo>} */
+export const foo = new Set([ 'a', 'b' ]);
+>foo : Symbol(foo, Decl(a.js, 13, 12))
+>Set : Symbol(Set, Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.collection.d.ts, --, --), Decl(lib.es2015.iterable.d.ts, --, --), Decl(lib.es2015.symbol.wellknown.d.ts, --, --), Decl(lib.esnext.collection.d.ts, --, --))
+
+/**
+ * @returns {Foo}
+ */
+function f4() { return 1; }
+>f4 : Symbol(f4, Decl(a.js, 13, 41))
+

tests/baselines/reference/importTag24.types

@@ -0,0 +1,74 @@
+//// [tests/cases/conformance/jsdoc/importTag24.ts] ////
+
+=== Performance Stats ===
+Type Count: 1,000
+Instantiation count: 2,500
+
+=== types.d.ts ===
+export type Foo = string;
+>Foo : string
+>    : ^^^^^^
+
+=== a.js ===
+/** @import { Foo } from './types.d.ts') */
+
+function f1() { return undefined; }
+>f1 : () => any
+>   : ^^^^^^^^^
+>undefined : undefined
+>          : ^^^^^^^^^
+
+export function f2() {
+>f2 : () => Set<string>
+>   : ^^^^^^^^^^^^^^^^^
+
+    /** @type {Set<Foo>} */
+    const foo = new Set([ 'a', 'b' ]);
+>foo : Set<string>
+>    : ^^^^^^^^^^^
+>new Set([ 'a', 'b' ]) : Set<string>
+>                      : ^^^^^^^^^^^
+>Set : SetConstructor
+>    : ^^^^^^^^^^^^^^
+>[ 'a', 'b' ] : string[]
+>             : ^^^^^^^^
+>'a' : "a"
+>    : ^^^
+>'b' : "b"
+>    : ^^^
+
+    return foo;
+>foo : Set<string>
+>    : ^^^^^^^^^^^
+}
+
+function f3() { return undefined; }
+>f3 : () => any
+>   : ^^^^^^^^^
+>undefined : undefined
+>          : ^^^^^^^^^
+
+/** @type {Set<Foo>} */
+export const foo = new Set([ 'a', 'b' ]);
+>foo : Set<string>
+>    : ^^^^^^^^^^^
+>new Set([ 'a', 'b' ]) : Set<string>
+>                      : ^^^^^^^^^^^
+>Set : SetConstructor
+>    : ^^^^^^^^^^^^^^
+>[ 'a', 'b' ] : string[]
+>             : ^^^^^^^^
+>'a' : "a"
+>    : ^^^
+>'b' : "b"
+>    : ^^^
+
+/**
+ * @returns {Foo}
+ */
+function f4() { return 1; }
+>f4 : () => Foo
+>   : ^^^^^^^^^
+>1 : 1
+>  : ^
+

tests/cases/conformance/jsdoc/importTag23.ts

@@ -0,0 +1,18 @@
+// @noUnusedLocals: true
+// @allowJs: true
+// @checkJs: true
+// @noEmit: true
+
+// @filename: types.d.ts
+export type T = {
+    a: number;
+};
+
+// @filename: foo.js
+/** @import { T } from "./types.d.ts" */
+
+export default async function f() {
+	/** @type {T[]} */
+	const types = [];
+	return types;
+}

tests/cases/conformance/jsdoc/importTag24.ts

@@ -0,0 +1,33 @@
+// @checkJs: true
+// @allowJs: true
+// @noEmit: true
+// @lib: esnext
+// @moduleResolution: bundler
+// @module: preserve
+// @noUnusedLocals: true
+// @noUnusedParameters: true
+// @allowImportingTsExtensions: true
+
+// @filename: types.d.ts
+export type Foo = string;
+
+// @filename: a.js
+/** @import { Foo } from './types.d.ts') */
+
+function f1() { return undefined; }
+
+export function f2() {
+    /** @type {Set<Foo>} */
+    const foo = new Set([ 'a', 'b' ]);
+    return foo;
+}
+
+function f3() { return undefined; }
+
+/** @type {Set<Foo>} */
+export const foo = new Set([ 'a', 'b' ]);
+
+/**
+ * @returns {Foo}
+ */
+function f4() { return 1; }