feat!: use type-only imports by default (#168)

BREAKING CHANGE: Since this package operates exclusively on types, it should be safe to use type-only imports. To restore the previous behavior, set `useTypeImports: false`. See https://www.typescriptlang.org/docs/handbook/modules/reference.html#type-only-imports-and-exports
mrgrain · Nov 18, 2023 · a07e971 · a07e971
1 parent abd7e4f
commit a07e971
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Showing 5 changed files with 16 additions and 16 deletions.
diff --git a/src/renderer/typescript.ts b/src/renderer/typescript.ts
@@ -43,7 +43,7 @@ export interface TypeScriptRendererOptions {
    * Use explicit `type` imports when importing referenced modules.
    *
    * @see https://www.typescriptlang.org/docs/handbook/modules.html#importing-types
-   * @default false
+   * @default true
    */
   readonly useTypeImports?: boolean;
 }
@@ -59,7 +59,7 @@ export class TypeScriptRenderer {
     this.options = {
       importLocations: options.importLocations ?? {},
       indent: options.indent ?? 2,
-      useTypeImports: options.useTypeImports ?? false,
+      useTypeImports: options.useTypeImports ?? true,
     };
     this.buffer = new CodeBuffer(' '.repeat(this.options.indent));
   }

diff --git a/test/projen/__snapshots__/projen-struct.test.ts.snap b/test/projen/__snapshots__/projen-struct.test.ts.snap
diff --git a/test/projen/__snapshots__/ts-interface.test.ts.snap b/test/projen/__snapshots__/ts-interface.test.ts.snap
diff --git a/test/projen/projen-struct.test.ts b/test/projen/projen-struct.test.ts
@@ -576,7 +576,7 @@ test('can import type from the same package at the top level', () => {
   const renderedFile = synthSnapshot(project)['src/MyInterface.ts'];
 
   // ASSERT
-  expect(renderedFile).toContain("import { more, OtherInterface } from './';");
+  expect(renderedFile).toContain("import type { more, OtherInterface } from './';");
 });
 
 test('can import type from the same package when nested', () => {
@@ -608,7 +608,7 @@ test('can import type from the same package when nested', () => {
 
   // ASSERT
   expect(renderedFile).toContain(
-    "import { more, OtherInterface } from '../../../';",
+    "import type { more, OtherInterface } from '../../../';",
   );
 });
 
@@ -641,7 +641,7 @@ test("can import type from the same package when in a location that's not matchi
   const renderedFile = synthSnapshot(project)['src/sub/MyInterface.ts'];
 
   // ASSERT
-  expect(renderedFile).toContain("import { more, OtherInterface } from '../';");
+  expect(renderedFile).toContain("import type { more, OtherInterface } from '../';");
 });
 
 test('can import type from an other package', () => {
@@ -665,7 +665,7 @@ test('can import type from an other package', () => {
   const renderedFile = synthSnapshot(project)['src/MyInterface.ts'];
 
   // ASSERT
-  expect(renderedFile).toContain("import { typescript } from 'projen';");
+  expect(renderedFile).toContain("import type { typescript } from 'projen';");
 });
 
 test('can override import locations', () => {
@@ -707,8 +707,8 @@ test('can override import locations', () => {
   const renderedFile = synthSnapshot(project)['src/MyInterface.ts'];
 
   // ASSERT
-  expect(renderedFile).toContain("import { more, OtherInterface } from 'bar';");
-  expect(renderedFile).toContain("import { typescript } from 'banana';");
+  expect(renderedFile).toContain("import type { more, OtherInterface } from 'bar';");
+  expect(renderedFile).toContain("import type { typescript } from 'banana';");
 });
 
 test('can use struct as type in add', () => {
@@ -744,7 +744,7 @@ test('can use struct as type in add', () => {
   expect(renderedNestedFile).toMatchSnapshot();
   expect(renderedNestedFile).toContain('@default .projenRC.ts');
   expect(renderedBaseFile).toMatchSnapshot();
-  expect(renderedBaseFile).toContain("import { MyInterface } from './'");
+  expect(renderedBaseFile).toContain("import type { MyInterface } from './'");
   expect(renderedBaseFile).toContain(
     'readonly projenrcTsOptions: MyInterface;',
   );
@@ -782,7 +782,7 @@ test('can use struct as type in update', () => {
 
   // ASSERT
   expect(renderedNestedFile).toContain('@default .projenRC.ts');
-  expect(renderedBaseFile).toContain("import { MyInterface } from './'");
+  expect(renderedBaseFile).toContain("import type { MyInterface } from './'");
   expect(renderedBaseFile).toContain(
     'readonly projenrcTsOptions?: MyInterface',
   );
@@ -833,7 +833,7 @@ test('can use an empty struct as type with name', () => {
   const renderedFile = synthSnapshot(project)['src/MyInterface.ts'];
 
   // ASSERT
-  expect(renderedFile).toContain("import { sub } from 'pkg';");
+  expect(renderedFile).toContain("import type { sub } from 'pkg';");
   expect(renderedFile).toContain('readonly nestedProp: sub.MyOtherInterface');
 });
 

diff --git a/test/projen/ts-interface.test.ts b/test/projen/ts-interface.test.ts
@@ -45,7 +45,7 @@ test('can import from an external package', () => {
 
   // ASSERT
   expect(renderedFile).toContain(
-    "import { javascript, typescript } from 'projen';",
+    "import type { javascript, typescript } from 'projen';",
   );
 });
 
@@ -69,7 +69,7 @@ test('can import from the same package', () => {
   const renderedFile = synthSnapshot(project)['interface.ts'];
 
   // ASSERT
-  expect(renderedFile).toContain("import { more, OtherInterface } from '../';");
+  expect(renderedFile).toContain("import type { more, OtherInterface } from '../';");
 });
 
 test('can override package imports', () => {
@@ -90,7 +90,7 @@ test('can override package imports', () => {
 
   // ASSERT
   expect(renderedFile).toContain(
-    "import { javascript, typescript } from 'banana';",
+    "import type { javascript, typescript } from 'banana';",
   );
 });