Import types in JS with var x = require('./mod') (#22161)

src/compiler/checker.ts

@@ -2049,6 +2049,18 @@ namespace ts {
                     if (initializer) {
                         namespace = getSymbolOfNode(initializer);
                     }
+                    if (namespace.valueDeclaration &&
+                        isVariableDeclaration(namespace.valueDeclaration) &&
+                        isCommonJsRequire(namespace.valueDeclaration.initializer)) {
+                        const moduleName = (namespace.valueDeclaration.initializer as CallExpression).arguments[0] as StringLiteral;
+                        const moduleSym = resolveExternalModuleName(moduleName, moduleName);
+                        if (moduleSym) {
+                            const resolvedModuleSymbol = resolveExternalModuleSymbol(moduleSym);
+                            if (resolvedModuleSymbol) {
+                                namespace = resolvedModuleSymbol;
+                            }
+                        }
+                    }
                 }
                 symbol = getSymbol(getExportsOfSymbol(namespace), right.escapedText, meaning);
                 if (!symbol) {
@@ -18133,7 +18145,7 @@ namespace ts {
 
             // In JavaScript files, calls to any identifier 'require' are treated as external module imports
             if (isInJavaScriptFile(node) && isCommonJsRequire(node)) {
-                return resolveExternalModuleTypeByLiteral(<StringLiteral>node.arguments[0]);
+                return resolveExternalModuleTypeByLiteral(node.arguments[0] as StringLiteral);
             }
 
             const returnType = getReturnTypeOfSignature(signature);

tests/baselines/reference/varRequireFromJavascript.errors.txt

@@ -0,0 +1,32 @@
+tests/cases/conformance/salsa/use.js(1,10): error TS2304: Cannot find name 'require'.
+
+
+==== tests/cases/conformance/salsa/use.js (1 errors) ====
+    var ex = require('./ex')
+             ~~~~~~~
+!!! error TS2304: Cannot find name 'require'.
+    
+    // values work
+    var crunch = new ex.Crunch(1);
+    crunch.n
+    
+    
+    // types work
+    /**
+     * @param {ex.Crunch} wrap
+     */
+    function f(wrap) {
+        wrap.n
+    }
+    
+==== tests/cases/conformance/salsa/ex.js (0 errors) ====
+    export class Crunch {
+        /** @param {number} n */
+        constructor(n) {
+            this.n = n
+        }
+        m() {
+            return this.n
+        }
+    }
+    

tests/baselines/reference/varRequireFromJavascript.symbols

@@ -0,0 +1,56 @@
+=== tests/cases/conformance/salsa/use.js ===
+var ex = require('./ex')
+>ex : Symbol(ex, Decl(use.js, 0, 3))
+>'./ex' : Symbol("tests/cases/conformance/salsa/ex", Decl(ex.js, 0, 0))
+
+// values work
+var crunch = new ex.Crunch(1);
+>crunch : Symbol(crunch, Decl(use.js, 3, 3))
+>ex.Crunch : Symbol(Crunch, Decl(ex.js, 0, 0))
+>ex : Symbol(ex, Decl(use.js, 0, 3))
+>Crunch : Symbol(Crunch, Decl(ex.js, 0, 0))
+
+crunch.n
+>crunch.n : Symbol(Crunch.n, Decl(ex.js, 2, 20))
+>crunch : Symbol(crunch, Decl(use.js, 3, 3))
+>n : Symbol(Crunch.n, Decl(ex.js, 2, 20))
+
+
+// types work
+/**
+ * @param {ex.Crunch} wrap
+ */
+function f(wrap) {
+>f : Symbol(f, Decl(use.js, 4, 8))
+>wrap : Symbol(wrap, Decl(use.js, 11, 11))
+
+    wrap.n
+>wrap.n : Symbol(Crunch.n, Decl(ex.js, 2, 20))
+>wrap : Symbol(wrap, Decl(use.js, 11, 11))
+>n : Symbol(Crunch.n, Decl(ex.js, 2, 20))
+}
+
+=== tests/cases/conformance/salsa/ex.js ===
+export class Crunch {
+>Crunch : Symbol(Crunch, Decl(ex.js, 0, 0))
+
+    /** @param {number} n */
+    constructor(n) {
+>n : Symbol(n, Decl(ex.js, 2, 16))
+
+        this.n = n
+>this.n : Symbol(Crunch.n, Decl(ex.js, 2, 20))
+>this : Symbol(Crunch, Decl(ex.js, 0, 0))
+>n : Symbol(Crunch.n, Decl(ex.js, 2, 20))
+>n : Symbol(n, Decl(ex.js, 2, 16))
+    }
+    m() {
+>m : Symbol(Crunch.m, Decl(ex.js, 4, 5))
+
+        return this.n
+>this.n : Symbol(Crunch.n, Decl(ex.js, 2, 20))
+>this : Symbol(Crunch, Decl(ex.js, 0, 0))
+>n : Symbol(Crunch.n, Decl(ex.js, 2, 20))
+    }
+}
+

tests/baselines/reference/varRequireFromJavascript.types

@@ -0,0 +1,61 @@
+=== tests/cases/conformance/salsa/use.js ===
+var ex = require('./ex')
+>ex : typeof "tests/cases/conformance/salsa/ex"
+>require('./ex') : typeof "tests/cases/conformance/salsa/ex"
+>require : any
+>'./ex' : "./ex"
+
+// values work
+var crunch = new ex.Crunch(1);
+>crunch : Crunch
+>new ex.Crunch(1) : Crunch
+>ex.Crunch : typeof Crunch
+>ex : typeof "tests/cases/conformance/salsa/ex"
+>Crunch : typeof Crunch
+>1 : 1
+
+crunch.n
+>crunch.n : number
+>crunch : Crunch
+>n : number
+
+
+// types work
+/**
+ * @param {ex.Crunch} wrap
+ */
+function f(wrap) {
+>f : (wrap: Crunch) => void
+>wrap : Crunch
+
+    wrap.n
+>wrap.n : number
+>wrap : Crunch
+>n : number
+}
+
+=== tests/cases/conformance/salsa/ex.js ===
+export class Crunch {
+>Crunch : Crunch
+
+    /** @param {number} n */
+    constructor(n) {
+>n : number
+
+        this.n = n
+>this.n = n : number
+>this.n : number
+>this : this
+>n : number
+>n : number
+    }
+    m() {
+>m : () => number
+
+        return this.n
+>this.n : number
+>this : this
+>n : number
+    }
+}
+

tests/baselines/reference/varRequireFromTypescript.errors.txt

@@ -0,0 +1,31 @@
+tests/cases/conformance/salsa/use.js(1,10): error TS2304: Cannot find name 'require'.
+
+
+==== tests/cases/conformance/salsa/use.js (1 errors) ====
+    var ex = require('./ex')
+             ~~~~~~~
+!!! error TS2304: Cannot find name 'require'.
+    
+    // values work
+    var crunch = new ex.Crunch(1);
+    crunch.n
+    
+    
+    // types work
+    /**
+     * @param {ex.Greatest} greatest
+     * @param {ex.Crunch} wrap
+     */
+    function f(greatest, wrap) {
+        greatest.day
+        wrap.n
+    }
+    
+==== tests/cases/conformance/salsa/ex.d.ts (0 errors) ====
+    export type Greatest = { day: 1 }
+    export class Crunch {
+        n: number
+        m(): number
+        constructor(n: number)
+    }
+    

tests/baselines/reference/varRequireFromTypescript.symbols

@@ -0,0 +1,57 @@
+=== tests/cases/conformance/salsa/use.js ===
+var ex = require('./ex')
+>ex : Symbol(ex, Decl(use.js, 0, 3))
+>'./ex' : Symbol("tests/cases/conformance/salsa/ex", Decl(ex.d.ts, 0, 0))
+
+// values work
+var crunch = new ex.Crunch(1);
+>crunch : Symbol(crunch, Decl(use.js, 3, 3))
+>ex.Crunch : Symbol(Crunch, Decl(ex.d.ts, 0, 33))
+>ex : Symbol(ex, Decl(use.js, 0, 3))
+>Crunch : Symbol(Crunch, Decl(ex.d.ts, 0, 33))
+
+crunch.n
+>crunch.n : Symbol(Crunch.n, Decl(ex.d.ts, 1, 21))
+>crunch : Symbol(crunch, Decl(use.js, 3, 3))
+>n : Symbol(Crunch.n, Decl(ex.d.ts, 1, 21))
+
+
+// types work
+/**
+ * @param {ex.Greatest} greatest
+ * @param {ex.Crunch} wrap
+ */
+function f(greatest, wrap) {
+>f : Symbol(f, Decl(use.js, 4, 8))
+>greatest : Symbol(greatest, Decl(use.js, 12, 11))
+>wrap : Symbol(wrap, Decl(use.js, 12, 20))
+
+    greatest.day
+>greatest.day : Symbol(day, Decl(ex.d.ts, 0, 24))
+>greatest : Symbol(greatest, Decl(use.js, 12, 11))
+>day : Symbol(day, Decl(ex.d.ts, 0, 24))
+
+    wrap.n
+>wrap.n : Symbol(Crunch.n, Decl(ex.d.ts, 1, 21))
+>wrap : Symbol(wrap, Decl(use.js, 12, 20))
+>n : Symbol(Crunch.n, Decl(ex.d.ts, 1, 21))
+}
+
+=== tests/cases/conformance/salsa/ex.d.ts ===
+export type Greatest = { day: 1 }
+>Greatest : Symbol(Greatest, Decl(ex.d.ts, 0, 0))
+>day : Symbol(day, Decl(ex.d.ts, 0, 24))
+
+export class Crunch {
+>Crunch : Symbol(Crunch, Decl(ex.d.ts, 0, 33))
+
+    n: number
+>n : Symbol(Crunch.n, Decl(ex.d.ts, 1, 21))
+
+    m(): number
+>m : Symbol(Crunch.m, Decl(ex.d.ts, 2, 13))
+
+    constructor(n: number)
+>n : Symbol(n, Decl(ex.d.ts, 4, 16))
+}
+

tests/baselines/reference/varRequireFromTypescript.types

@@ -0,0 +1,61 @@
+=== tests/cases/conformance/salsa/use.js ===
+var ex = require('./ex')
+>ex : typeof "tests/cases/conformance/salsa/ex"
+>require('./ex') : typeof "tests/cases/conformance/salsa/ex"
+>require : any
+>'./ex' : "./ex"
+
+// values work
+var crunch = new ex.Crunch(1);
+>crunch : Crunch
+>new ex.Crunch(1) : Crunch
+>ex.Crunch : typeof Crunch
+>ex : typeof "tests/cases/conformance/salsa/ex"
+>Crunch : typeof Crunch
+>1 : 1
+
+crunch.n
+>crunch.n : number
+>crunch : Crunch
+>n : number
+
+
+// types work
+/**
+ * @param {ex.Greatest} greatest
+ * @param {ex.Crunch} wrap
+ */
+function f(greatest, wrap) {
+>f : (greatest: { day: 1; }, wrap: Crunch) => void
+>greatest : { day: 1; }
+>wrap : Crunch
+
+    greatest.day
+>greatest.day : 1
+>greatest : { day: 1; }
+>day : 1
+
+    wrap.n
+>wrap.n : number
+>wrap : Crunch
+>n : number
+}
+
+=== tests/cases/conformance/salsa/ex.d.ts ===
+export type Greatest = { day: 1 }
+>Greatest : Greatest
+>day : 1
+
+export class Crunch {
+>Crunch : Crunch
+
+    n: number
+>n : number
+
+    m(): number
+>m : () => number
+
+    constructor(n: number)
+>n : number
+}
+

tests/cases/conformance/salsa/varRequireFromJavascript.ts

@@ -0,0 +1,30 @@
+// @allowJs: true
+// @checkJs: true
+// @strict: true
+// @noEmit: true
+// @Filename: ex.js
+export class Crunch {
+    /** @param {number} n */
+    constructor(n) {
+        this.n = n
+    }
+    m() {
+        return this.n
+    }
+}
+
+// @Filename: use.js
+var ex = require('./ex')
+
+// values work
+var crunch = new ex.Crunch(1);
+crunch.n
+
+
+// types work
+/**
+ * @param {ex.Crunch} wrap
+ */
+function f(wrap) {
+    wrap.n
+}

tests/cases/conformance/salsa/varRequireFromTypescript.ts

@@ -0,0 +1,29 @@
+// @allowJs: true
+// @checkJs: true
+// @strict: true
+// @noEmit: true
+// @Filename: ex.d.ts
+export type Greatest = { day: 1 }
+export class Crunch {
+    n: number
+    m(): number
+    constructor(n: number)
+}
+
+// @Filename: use.js
+var ex = require('./ex')
+
+// values work
+var crunch = new ex.Crunch(1);
+crunch.n
+
+
+// types work
+/**
+ * @param {ex.Greatest} greatest
+ * @param {ex.Crunch} wrap
+ */
+function f(greatest, wrap) {
+    greatest.day
+    wrap.n
+}