Update: add proper scope analysis (fixes #535) (#540)

* Update: add proper scope analysis (fixes #535)

* add computed-properties-in-type fixture

* add computed-properties-in-interface fixture

* add function-overload fixture

* add method-overload fixture

* add class-properties fixture

* add decorators fixture

* update visitor-keys

* add declare-global fixture

* fix typo

* add test for typeof in array destructuring

* add namespace fixture

* add declare-module fixture

* fix crash

* add declare-function.ts fixture

* add abstract-class fixture

* add typeof-in-call-signature fixture

* add test for #416

* add test for #435

* add test for #437

* add test for #443

* add test for #459

* add test for #466

* add test for #471

* add test for #487

* add test for #535

* add test for #536

* add test for #476

* fix test to use `expect()`

package.json

@@ -7,6 +7,7 @@
   "version": "20.1.1",
   "files": [
     "parser.js",
+    "analyze-scope.js",
     "visitor-keys.js"
   ],
   "engines": {
@@ -43,7 +44,9 @@
     "typescript": "*"
   },
   "dependencies": {
+    "eslint-scope": "^4.0.0",
     "eslint-visitor-keys": "^1.0.0",
+    "lodash": "^4.17.11",
     "typescript-estree": "5.0.0"
   },
   "devDependencies": {

parser.js

@@ -11,6 +11,7 @@
 const parse = require("typescript-estree").parse;
 const astNodeTypes = require("typescript-estree").AST_NODE_TYPES;
 const traverser = require("eslint/lib/util/traverser");
+const analyzeScope = require("./analyze-scope");
 const visitorKeys = require("./visitor-keys");
 
 //------------------------------------------------------------------------------
@@ -33,16 +34,45 @@ exports.parseForESLint = function parseForESLint(code, options) {
     }
 
     const ast = parse(code, options);
+    const extraOptions = {
+        sourceType: ast.sourceType
+    };
+
     traverser.traverse(ast, {
         enter: node => {
-            if (node.type === "DeclareFunction" || node.type === "FunctionExpression" || node.type === "FunctionDeclaration") {
-                if (!node.body) {
-                    node.type = `TSEmptyBody${node.type}`;
-                }
+            switch (node.type) {
+                // Just for backword compatibility.
+                case "DeclareFunction":
+                    if (!node.body) {
+                        node.type = `TSEmptyBody${node.type}`;
+                    }
+                    break;
+
+                // Function#body cannot be null in ESTree spec.
+                case "FunctionExpression":
+                case "FunctionDeclaration":
+                    if (!node.body) {
+                        node.type = `TSEmptyBody${node.type}`;
+                    }
+                    break;
+
+                // Import/Export declarations cannot appear in script.
+                // But if those appear only in namespace/module blocks, `ast.sourceType` was `"script"`.
+                // This doesn't modify `ast.sourceType` directly for backrard compatibility.
+                case "ImportDeclaration":
+                case "ExportAllDeclaration":
+                case "ExportDefaultDeclaration":
+                case "ExportNamedDeclaration":
+                    extraOptions.sourceType = "module";
+                    break;
+
+                // no default
             }
         }
     });
-    return { ast, visitorKeys };
+
+    const scopeManager = analyzeScope(ast, options, extraOptions);
+    return { ast, scopeManager, visitorKeys };
 };
 
 exports.parse = function(code, options) {

tests/fixtures/scope-analysis/535.ts

@@ -0,0 +1,3 @@
+function foo({ bar }: { bar: string }) {
+    bar;
+}

tests/fixtures/scope-analysis/abstract-class.ts

@@ -0,0 +1,4 @@
+abstract class A {
+    abstract a: string
+    abstract f(): number
+}

tests/fixtures/scope-analysis/class-properties.ts

@@ -0,0 +1,5 @@
+const s = Symbol()
+class A {
+    a: typeof s
+    [s]: number
+}

tests/fixtures/scope-analysis/computed-properties-in-interface.ts

@@ -0,0 +1,5 @@
+const s1 = Symbol(), s2 = Symbol()
+interface A {
+    [s1]: number
+    [s2](s1: number, s2: number): number;
+}

tests/fixtures/scope-analysis/computed-properties-in-type.ts

@@ -0,0 +1,5 @@
+const s1 = Symbol(), s2 = Symbol()
+type A = {
+    [s1]: number
+    [s2](s1: number, s2: number): number;
+}

tests/fixtures/scope-analysis/declare-function.ts

@@ -0,0 +1,2 @@
+declare function f(a: number): number
+f

tests/fixtures/scope-analysis/declare-global.ts

@@ -0,0 +1,7 @@
+declare global {
+    let C: number
+}
+
+C = 1
+
+export {}

tests/fixtures/scope-analysis/declare-module.ts

@@ -0,0 +1,6 @@
+const a = 1
+declare module "foo" {
+    export const a: number
+    export const b: typeof a
+}
+a

tests/fixtures/scope-analysis/decorators.ts

@@ -0,0 +1,13 @@
+function dec(target: any) {
+}
+function gec() {
+    return (target: any, propertyKey: string) => {}
+}
+
+@dec
+class C {
+    @gec() field: string
+    @gec() method(): string {
+        return ""
+    }
+}

tests/fixtures/scope-analysis/enum.ts

@@ -0,0 +1,6 @@
+const a: number = 1
+enum E {
+    A = a,
+    B = a + 1,
+    C = A + B
+}

tests/fixtures/scope-analysis/function-overload-2.ts

@@ -0,0 +1,2 @@
+function f(): void
+function f(a: number): void

tests/fixtures/scope-analysis/function-overload.ts

@@ -0,0 +1,5 @@
+function f(): void
+function f(a: number): void
+function f(a?: number): void {
+    // do something.
+}

tests/fixtures/scope-analysis/ignore-type-only-stuff.ts

@@ -0,0 +1,9 @@
+type A = number
+interface B {
+    prop1: A
+}
+interface C extends B {
+    method(a: { b: A }): { c: A }
+}
+
+var a: C

tests/fixtures/scope-analysis/method-overload.ts

@@ -0,0 +1,8 @@
+const s = Symbol()
+class A {
+    f(): void
+    f(a: typeof s): void
+    f(a?: any): void {
+        // do something.
+    }
+}

tests/fixtures/scope-analysis/namespace.ts

@@ -0,0 +1,7 @@
+const a = 1
+namespace N {
+    export const a = 2
+    a
+}
+a
+N.a

tests/fixtures/scope-analysis/type-annotations.ts

@@ -0,0 +1,7 @@
+type A = number
+var a: { b: A }
+class C {
+    f(a: { b: A }): { b: A } {
+        return {b: 1}
+    }
+}

tests/fixtures/scope-analysis/type-assertions.ts

@@ -0,0 +1,3 @@
+type A = number;
+a = <A> b;
+a = b as A;

tests/fixtures/scope-analysis/typeof-in-assertions.ts

@@ -0,0 +1,3 @@
+var obj = { value: 1 }
+a = <typeof obj>b;
+a = b as typeof obj;

tests/fixtures/scope-analysis/typeof-in-call-signature.ts

@@ -0,0 +1,5 @@
+const obj = { value: 1 }
+interface A {
+    <T extends typeof obj>(a: typeof obj, b: T): typeof obj
+    new <T extends typeof obj>(a: typeof obj, b: T): typeof obj
+}

tests/fixtures/scope-analysis/typeof-in-return-type.ts

@@ -0,0 +1,3 @@
+function f(a: number): typeof a { // this `a` is the parameter `a`.
+    return 1
+}

tests/fixtures/scope-analysis/typeof-in-type-parameters.ts

@@ -0,0 +1,3 @@
+function g<T extends typeof g>(g: T): number {
+    return 1
+}

tests/fixtures/scope-analysis/typeof-in-var.ts

@@ -0,0 +1,4 @@
+var obj = { value: 1 }
+var obj2: typeof obj = { value: 2 }
+var { value }: typeof obj = { value: 2 }
+var [element]: (typeof obj)[] = [{ value: 2 }]

tests/fixtures/scope-analysis/typeof.ts

@@ -0,0 +1,2 @@
+var obj = { value: 1 }
+type B = typeof obj