fix: remove dts empty line (#446)

Co-authored-by: Anthony Fu <anthonyfu117@hotmail.com>

Author: sxzz

src/core/declaration.ts

@@ -127,8 +127,7 @@ declare module '@vue/runtime-core' {`
     code += `
   export interface GlobalComponents {
     ${declarations.component.join('\n    ')}
-  }
-`
+  }`
   }
   if (Object.keys(declarations.directive).length > 0) {
     code += `

test/__snapshots__/dts.test.ts.snap

@@ -1,6 +1,6 @@
 // Vitest Snapshot v1
 
-exports[`dts > getDeclaration 1`] = `
+exports[`dts > components only 1`] = `
 "// generated by unplugin-vue-components
 // We suggest you to commit this file into source control
 // Read more: https://github.com/vuejs/core/pull/3399
@@ -14,7 +14,40 @@ declare module '@vue/runtime-core' {
     RouterView: typeof import('vue-router')['RouterView']
     TestComp: typeof import('test/component/TestComp')['default']
   }
+}
+"
+`;
+
+exports[`dts > directive only 1`] = `
+"// generated by unplugin-vue-components
+// We suggest you to commit this file into source control
+// Read more: https://github.com/vuejs/core/pull/3399
+import '@vue/runtime-core'
 
+export {}
+
+declare module '@vue/runtime-core' {
+  export interface ComponentCustomProperties {
+    vLoading: typeof import('test/directive/Loading')['default']
+  }
+}
+"
+`;
+
+exports[`dts > getDeclaration 1`] = `
+"// generated by unplugin-vue-components
+// We suggest you to commit this file into source control
+// Read more: https://github.com/vuejs/core/pull/3399
+import '@vue/runtime-core'
+
+export {}
+
+declare module '@vue/runtime-core' {
+  export interface GlobalComponents {
+    RouterLink: typeof import('vue-router')['RouterLink']
+    RouterView: typeof import('vue-router')['RouterView']
+    TestComp: typeof import('test/component/TestComp')['default']
+  }
   export interface ComponentCustomProperties {
     vLoading: typeof import('test/directive/Loading')['default']
   }
@@ -74,7 +107,6 @@ declare module '@vue/runtime-core' {
     SomeComp: typeof import('test/component/SomeComp')['default']
     TestComp: typeof import('test/component/TestComp')['default']
   }
-
   export interface ComponentCustomProperties {
     vDirective: typeof import('foo')
     vLoading: typeof import('test/directive/Loading')['default']
@@ -98,7 +130,6 @@ declare module '@vue/runtime-core' {
     RouterView: typeof import('vue-router')['RouterView']
     TestComp: typeof import('test/component/TestComp')['default']
   }
-
   export interface ComponentCustomProperties {
     vLoading: typeof import('test/directive/Loading')['default']
   }

test/dts.test.ts

@@ -83,6 +83,31 @@ const _directive_loading = _resolveDirective("loading")`
     expect(contents).toContain('vSome')
   })
 
+  test('components only', async () => {
+    const ctx = new Context({
+      resolvers: resolver,
+      directives: true,
+    })
+    const code = 'const _component_test_comp = _resolveComponent("test-comp")'
+    await ctx.transform(code, '')
+
+    const declarations = getDeclaration(ctx, 'test.d.ts')
+    expect(declarations).toMatchSnapshot()
+  })
+
+  test('directive only', async () => {
+    const ctx = new Context({
+      resolvers: resolver,
+      directives: true,
+      types: [],
+    })
+    const code = 'const _directive_loading = _resolveDirective("loading")'
+    await ctx.transform(code, '')
+
+    const declarations = getDeclaration(ctx, 'test.d.ts')
+    expect(declarations).toMatchSnapshot()
+  })
+
   test('parseDeclaration', async () => {
     const code = `
 // generated by unplugin-vue-components