Improve module transform packages typings

packages/babel-helper-module-transforms/src/index.ts

@@ -27,7 +27,9 @@ import normalizeModuleAndLoadMetadata, {
   validateImportInteropOption,
 } from "./normalize-and-load-metadata";
 import type {
+  ImportInterop,
   InteropType,
+  Lazy,
   ModuleMetadata,
   SourceModuleMetadata,
 } from "./normalize-and-load-metadata";
@@ -38,6 +40,22 @@ export type { PluginOptions } from "./get-module-name";
 
 export { hasExports, isSideEffectImport, isModule, rewriteThis };
 
+export interface RewriteModuleStatementsAndPrepareHeaderOptions {
+  exportName?: string;
+  strict: boolean;
+  allowTopLevelThis?: boolean;
+  strictMode: boolean;
+  loose?: boolean;
+  importInterop?: ImportInterop;
+  noInterop?: boolean;
+  lazy?: Lazy;
+  esNamespaceOnly?: boolean;
+  filename: string | undefined;
+  constantReexports?: boolean | void;
+  enumerableModuleMeta?: boolean | void;
+  noIncompleteNsImportDetection?: boolean | void;
+}
+
 /**
  * Perform all of the generic ES6 module rewriting needed to handle initial
  * module processing. This function will rewrite the majority of the given
@@ -63,21 +81,7 @@ export function rewriteModuleStatementsAndPrepareHeader(
     constantReexports = loose,
     enumerableModuleMeta = loose,
     noIncompleteNsImportDetection,
-  }: {
-    exportName?;
-    strict;
-    allowTopLevelThis?;
-    strictMode;
-    loose?;
-    importInterop?: "none" | "babel" | "node";
-    noInterop?;
-    lazy?;
-    esNamespaceOnly?;
-    filename: string | undefined;
-    constantReexports?;
-    enumerableModuleMeta?;
-    noIncompleteNsImportDetection?: boolean;
-  },
+  }: RewriteModuleStatementsAndPrepareHeaderOptions,
 ) {
   validateImportInteropOption(importInterop);
   assert(isModule(path), "Cannot process module statements in a script");
@@ -138,9 +142,10 @@ export function rewriteModuleStatementsAndPrepareHeader(
  * Flag a set of statements as hoisted above all else so that module init
  * statements all run before user code.
  */
-export function ensureStatementsHoisted(statements) {
+export function ensureStatementsHoisted(statements: t.Statement[]) {
   // Force all of the header fields to be at the top of the file.
   statements.forEach(header => {
+    // @ts-ignore Fixme: handle _blockHoist property
     header._blockHoist = 3;
   });
 }
@@ -303,7 +308,7 @@ const buildReexportsFromMeta = (
  */
 function buildESModuleHeader(
   metadata: ModuleMetadata,
-  enumerableModuleMeta: boolean = false,
+  enumerableModuleMeta: boolean | void = false,
 ) {
   return (
     enumerableModuleMeta
@@ -321,7 +326,11 @@ function buildESModuleHeader(
 /**
  * Create a re-export initialization loop for a specific imported namespace.
  */
-function buildNamespaceReexport(metadata, namespace, constantReexports) {
+function buildNamespaceReexport(
+  metadata: ModuleMetadata,
+  namespace: t.Identifier | t.CallExpression,
+  constantReexports: boolean | void,
+) {
   return (
     constantReexports
       ? template.statement`
@@ -413,8 +422,8 @@ function buildExportNameListDeclaration(
 function buildExportInitializationStatements(
   programPath: NodePath,
   metadata: ModuleMetadata,
-  constantReexports: boolean = false,
-  noIncompleteNsImportDetection = false,
+  constantReexports: boolean | void = false,
+  noIncompleteNsImportDetection: boolean | void = false,
 ) {
   const initStatements: Array<[string, t.Statement | null]> = [];
 
@@ -514,7 +523,11 @@ const InitTemplate = {
   default: template.expression`EXPORTS.NAME = VALUE`,
 };
 
-function buildInitStatement(metadata: ModuleMetadata, exportNames, initExpr) {
+function buildInitStatement(
+  metadata: ModuleMetadata,
+  exportNames: string[],
+  initExpr: t.Expression,
+) {
   const { stringSpecifiers, exportName: EXPORTS } = metadata;
   return expressionStatement(
     exportNames.reduce((acc, exportName) => {

packages/babel-helper-module-transforms/src/normalize-and-load-metadata.ts

@@ -28,6 +28,14 @@ export type InteropType =
   | "node-namespace" // Node.js interop for namespace or default+named imports
   | "none"; // No interop, or named-only imports
 
+export type ImportInterop =
+  | "none"
+  | "babel"
+  | "node"
+  | ((source: string, filename?: string) => "none" | "babel" | "node");
+
+export type Lazy = boolean | string[] | ((source: string) => boolean);
+
 export interface SourceModuleMetadata {
   // A unique variable name to use for this namespace object. Centralized for simplicity.
   name: string;
@@ -45,7 +53,7 @@ export interface SourceModuleMetadata {
   reexportAll: null | {
     loc: t.SourceLocation | undefined | null;
   };
-  lazy?;
+  lazy?: Lazy;
 }
 
 export interface LocalExportMetadata {
@@ -75,7 +83,7 @@ export function isSideEffectImport(source: SourceModuleMetadata) {
 
 export function validateImportInteropOption(
   importInterop: any,
-): importInterop is "none" | "babel" | "node" | Function {
+): importInterop is ImportInterop {
   if (
     typeof importInterop !== "function" &&
     importInterop !== "none" &&
@@ -90,8 +98,8 @@ export function validateImportInteropOption(
 }
 
 function resolveImportInterop(
-  importInterop,
-  source,
+  importInterop: ImportInterop,
+  source: string,
   filename: string | undefined,
 ) {
   if (typeof importInterop === "function") {
@@ -113,6 +121,12 @@ export default function normalizeModuleAndLoadMetadata(
     lazy = false,
     esNamespaceOnly = false,
     filename,
+  }: {
+    importInterop: ImportInterop;
+    initializeReexports: boolean | void;
+    lazy: Lazy;
+    esNamespaceOnly: boolean;
+    filename: string;
   },
 ): ModuleMetadata {
   if (!exportName) {
@@ -219,8 +233,8 @@ function getModuleMetadata(
     initializeReexports,
   }: {
     // todo(flow-ts) changed from boolean, to match expected usage inside the function
-    lazy: boolean | string[] | Function;
-    initializeReexports: boolean;
+    lazy: boolean | string[] | ((source: string) => boolean);
+    initializeReexports: boolean | void;
   },
   stringSpecifiers: Set<string>,
 ) {
@@ -231,7 +245,7 @@ function getModuleMetadata(
   );
 
   const sourceData = new Map();
-  const getData = sourceNode => {
+  const getData = (sourceNode: t.StringLiteral) => {
     const source = sourceNode.value;
 
     let data = sourceData.get(source);
@@ -409,22 +423,26 @@ function getModuleMetadata(
   };
 }
 
+type ModuleBindingKind = "import" | "hoisted" | "block" | "var";
 /**
  * Get metadata about local variables that are exported.
  */
 function getLocalExportMetadata(
   programPath: NodePath<t.Program>,
-  initializeReexports: boolean,
+  initializeReexports: boolean | void,
   stringSpecifiers: Set<string>,
 ): Map<string, LocalExportMetadata> {
   const bindingKindLookup = new Map();
 
-  programPath.get("body").forEach((child: any) => {
-    let kind;
+  programPath.get("body").forEach(child => {
+    let kind: ModuleBindingKind;
     if (child.isImportDeclaration()) {
       kind = "import";
     } else {
-      if (child.isExportDefaultDeclaration()) child = child.get("declaration");
+      if (child.isExportDefaultDeclaration()) {
+        // @ts-ignore
+        child = child.get("declaration");
+      }
       if (child.isExportNamedDeclaration()) {
         if (child.node.declaration) {
           child = child.get("declaration");
@@ -460,7 +478,7 @@ function getLocalExportMetadata(
   });
 
   const localMetadata = new Map();
-  const getLocalMetadata = idPath => {
+  const getLocalMetadata = (idPath: NodePath<t.Identifier>) => {
     const localName = idPath.node.name;
     let metadata = localMetadata.get(localName);
 

packages/babel-helper-module-transforms/src/rewrite-live-references.ts

@@ -27,24 +27,24 @@ import type { ModuleMetadata } from "./normalize-and-load-metadata";
 interface RewriteReferencesVisitorState {
   exported: Map<any, any>;
   metadata: ModuleMetadata;
-  requeueInParent: (path) => void;
+  requeueInParent: (path: NodePath) => void;
   scope: Scope;
   imported: Map<any, any>;
   buildImportReference: (
-    [source, importName, localName]: readonly [any, any, any],
-    identNode,
+    [source, importName, localName]: readonly [string, string, string],
+    identNode: t.Identifier | t.CallExpression | t.JSXIdentifier,
   ) => any;
   seen: WeakSet<object>;
 }
 
 interface RewriteBindingInitVisitorState {
   exported: Map<any, any>;
   metadata: ModuleMetadata;
-  requeueInParent: (path) => void;
+  requeueInParent: (path: NodePath) => void;
   scope: Scope;
 }
 
-function isInType(path) {
+function isInType(path: NodePath) {
   do {
     switch (path.parent.type) {
       case "TSTypeAnnotation":
@@ -54,7 +54,13 @@ function isInType(path) {
       case "TypeAlias":
         return true;
       case "ExportSpecifier":
-        return path.parentPath.parent.exportKind === "type";
+        return (
+          (
+            path.parentPath.parent as
+              | t.ExportDefaultDeclaration
+              | t.ExportNamedDeclaration
+          ).exportKind === "type"
+        );
       default:
         if (path.parentPath.isStatement() || path.parentPath.isExpression()) {
           return false;
@@ -69,7 +75,7 @@ export default function rewriteLiveReferences(
 ) {
   const imported = new Map();
   const exported = new Map();
-  const requeueInParent = path => {
+  const requeueInParent = (path: NodePath) => {
     // Manually re-queue `exports.default =` expressions so that the ES3
     // transform has an opportunity to convert them. Ideally this would
     // happen automatically from the replaceWith above. See #4140 for
@@ -127,7 +133,13 @@ export default function rewriteLiveReferences(
       const meta = metadata.source.get(source);
 
       if (localName) {
-        if (meta.lazy) identNode = callExpression(identNode, []);
+        if (meta.lazy) {
+          identNode = callExpression(
+            // @ts-expect-error Fixme: we should handle the case when identNode is a JSXIdentifier
+            identNode,
+            [],
+          );
+        }
         return identNode;
       }
 
@@ -203,9 +215,9 @@ const rewriteBindingInitVisitor: Visitor<RewriteBindingInitVisitorState> = {
 };
 
 const buildBindingExportAssignmentExpression = (
-  metadata,
-  exportNames,
-  localExpr,
+  metadata: ModuleMetadata,
+  exportNames: string[],
+  localExpr: t.Expression,
 ) => {
   return (exportNames || []).reduce((expr, exportName) => {
     // class Foo {} export { Foo, Foo as Bar };
@@ -225,7 +237,7 @@ const buildBindingExportAssignmentExpression = (
   }, localExpr);
 };
 
-const buildImportThrow = localName => {
+const buildImportThrow = (localName: string) => {
   return template.expression.ast`
     (function() {
       throw new Error('"' + '${localName}' + '" is read-only.');
@@ -403,7 +415,7 @@ const rewriteReferencesVisitor: Visitor<RewriteReferencesVisitorState> = {
           const assignment = path.node;
 
           if (importData) {
-            assignment.left = buildImportReference(importData, assignment.left);
+            assignment.left = buildImportReference(importData, left.node);
 
             assignment.right = sequenceExpression([
               assignment.right,
@@ -437,7 +449,7 @@ const rewriteReferencesVisitor: Visitor<RewriteReferencesVisitorState> = {
 
         // Complex ({a, b, c} = {}); export { a, c };
         // =>   ({a, b, c} = {}), (exports.a = a, exports.c = c);
-        const items = [];
+        const items: t.Expression[] = [];
         programScopeIds.forEach(localName => {
           const exportedNames = exported.get(localName) || [];
           if (exportedNames.length > 0) {

packages/babel-helper-module-transforms/src/rewrite-this.ts

@@ -1,7 +1,6 @@
 import environmentVisitor from "@babel/helper-environment-visitor";
 import traverse from "@babel/traverse";
 import { numericLiteral, unaryExpression } from "@babel/types";
-import type * as t from "@babel/types";
 
 import type { NodePath, Visitor } from "@babel/traverse";
 export default function rewriteThis(programPath: NodePath) {
@@ -16,7 +15,7 @@ export default function rewriteThis(programPath: NodePath) {
 const rewriteThisVisitor: Visitor = traverse.visitors.merge([
   environmentVisitor,
   {
-    ThisExpression(path: NodePath<t.ThisExpression>) {
+    ThisExpression(path) {
       path.replaceWith(unaryExpression("void", numericLiteral(0), true));
     },
   },