Fix issues with JavaScript importing JavaScript. (denoland#4120)

Fixes denoland#3852
Fixes denoland#4117

cli/js/compiler_host.ts

@@ -47,18 +47,18 @@ export const defaultBundlerOptions: ts.CompilerOptions = {
 
 /** Default options used by the compiler Host when compiling. */
 export const defaultCompileOptions: ts.CompilerOptions = {
- allowJs: true,
+ allowJs: false,
  allowNonTsExtensions: true,
- strict: true,
  checkJs: false,
  esModuleInterop: true,
+ jsx: ts.JsxEmit.React,
  module: ts.ModuleKind.ESNext,
  outDir: OUT_DIR,
  resolveJsonModule: true,
  sourceMap: true,
+ strict: true,
  stripComments: true,
- target: ts.ScriptTarget.ESNext,
- jsx: ts.JsxEmit.React
+ target: ts.ScriptTarget.ESNext
 };
 
 /** Options that need to be used when doing a runtime (non bundled) compilation */

cli/js/compiler_util.ts

@@ -304,7 +304,11 @@ export const ignoredDiagnostics = [
  // support JSON imports. Allegedly this was fixed in
  // Microsoft/TypeScript#26825 but that doesn't seem to be working here,
  // so we will ignore complaints about this compiler setting.
- 5070
+ 5070,
+ // TS7016: Could not find a declaration file for module '...'. '...'
+ // implicitly has an 'any' type. This is due to `allowJs` being off by
+ // default but importing of a JavaScript module.
+ 7016
 ];
 
 /** When doing a host configuration, processing the response and logging out

cli/tests/038_checkjs.tsconfig.json

@@ -1,5 +1,6 @@
 {
  "compilerOptions": {
+ "allowJs": true,
  "checkJs": true
  }
 }

cli/tests/fix_js_import_js.ts

@@ -0,0 +1,3 @@
+import { isMod4 } from "./subdir/mod6.js";
+
+console.log(isMod4);

cli/tests/fix_js_import_js.ts.out

@@ -0,0 +1 @@
+true

cli/tests/integration_tests.rs

@@ -1160,6 +1160,11 @@ itest!(cafile_info {
  http_server: true,
 });
 
+itest!(fix_js_import_js {
+ args: "run --reload fix_js_import_js.ts",
+ output: "fix_js_import_js.ts.out",
+});
+
 itest!(fix_js_imports {
  args: "run --reload fix_js_imports.ts",
  output: "fix_js_imports.ts.out",

cli/tests/subdir/mod6.js

@@ -0,0 +1 @@
+export { isMod4 } from "./mod4.js";