Fix import clause overload and apply prettier

Switch helper_types.ts back to SyntaxKind.TypeKeyword to match google#213.

Also run npm run fix:prettier to apply the requested TS/MD formatting updates.

Author: cochinescu

README.md

@@ -59,9 +59,9 @@ const p: WithContext<Person> = {
 
 ### Merging multiple concrete types
 
-Some Schema.org objects can legitimately carry multiple concrete `@type`
-values. For those advanced cases, `schema-dts` exports leaf types alongside the
-usual union aliases, plus a `MergeLeafTypes` helper for combining them:
+Some Schema.org objects can legitimately carry multiple concrete `@type` values.
+For those advanced cases, `schema-dts` exports leaf types alongside the usual
+union aliases, plus a `MergeLeafTypes` helper for combining them:
 
 ```ts
 import type {

packages/schema-dts-gen/src/ts/helper_types.ts

@@ -99,7 +99,7 @@ export function HelperTypes(context: Context, {hasRole}: {hasRole: boolean}) {
     factory.createImportDeclaration(
       /*modifiers=*/ [],
       factory.createImportClause(
-        /*isTypeOnly=*/ true,
+        SyntaxKind.TypeKeyword,
         /*name=*/ undefined,
         factory.createNamedImports([
           factory.createImportSpecifier(

packages/schema-dts-lib/index.ts

@@ -25,9 +25,8 @@ type UnionToIntersection<T> = (
   ? I
   : never;
 
-type CheckLeaf<T extends LeafLike> = UnionToIntersection<T['@type']> extends never
-  ? LeafTypesError<T>
-  : T;
+type CheckLeaf<T extends LeafLike> =
+  UnionToIntersection<T['@type']> extends never ? LeafTypesError<T> : T;
 
 type OmitTypeProperty<T extends LeafLike> = T extends unknown
   ? Omit<T, '@type'>

packages/schema-dts/README.md

@@ -82,23 +82,22 @@ import type {
   WithContext,
 } from 'schema-dts';
 
-const app: WithContext<
-  MergeLeafTypes<[ProductLeaf, SoftwareApplicationLeaf]>
-> = {
-  '@context': 'https://schema.org',
-  '@type': ['Product', 'SoftwareApplication'],
-  name: 'My App',
-  offers: {
-    '@type': 'Offer',
-    price: 89,
-    priceCurrency: 'USD',
-  },
-  operatingSystem: 'Any',
-};
+const app: WithContext<MergeLeafTypes<[ProductLeaf, SoftwareApplicationLeaf]>> =
+  {
+    '@context': 'https://schema.org',
+    '@type': ['Product', 'SoftwareApplication'],
+    name: 'My App',
+    offers: {
+      '@type': 'Offer',
+      price: 89,
+      priceCurrency: 'USD',
+    },
+    operatingSystem: 'Any',
+  };
 ```
 
-`MergeLeafTypes` is intended for concrete leaf types like `ProductLeaf`, not
-for union aliases like `Product`.
+`MergeLeafTypes` is intended for concrete leaf types like `ProductLeaf`, not for
+union aliases like `Product`.
 
 ### Graphs and IDs