test: typescript utils

Author: sean-perkins

packages/cli/src/angular/utils/typescript-utils.test.ts

@@ -40,9 +40,26 @@ describe("getOrCreateConstructor", () => {
 
 describe("addImportToClass", () => {
   it("should add an import to a class", () => {
+    const sourceFileContent = `export class Foo { }`;
+
+    const project = new Project({ useInMemoryFileSystem: true });
+    const sourceFile = project.createSourceFile("foo.ts", sourceFileContent);
+
+    addImportToClass(sourceFile, "Component", "@angular/core");
+
+    expect(dedent(sourceFile.getText())).toBe(
+      dedent(`
+    import { Component } from "@angular/core";
+
+    export class Foo { }
+    `),
+    );
+  });
+
+  it("should add an import to an existing import declaration", () => {
     const sourceFileContent = `
-      export class Foo {
-      }
+    import { Injectable } from "@angular/core";
+    export class Foo { }
     `;
 
     const project = new Project({ useInMemoryFileSystem: true });
@@ -52,11 +69,42 @@ describe("addImportToClass", () => {
 
     expect(dedent(sourceFile.getText())).toBe(
       dedent(`
-    import { Component } from "@angular/core";
+    import { Injectable, Component } from "@angular/core";
+    export class Foo { }
+    `),
+    );
+  });
 
-    export class Foo {
-    }
+  it("should add multiple imports", () => {
+    const sourceFileContent = `export class Foo { }`;
+
+    const project = new Project({ useInMemoryFileSystem: true });
+    const sourceFile = project.createSourceFile("foo.ts", sourceFileContent);
+
+    addImportToClass(sourceFile, ["Component", "Injectable"], "@angular/core");
+
+    expect(dedent(sourceFile.getText())).toBe(
+      dedent(`
+    import { Component, Injectable } from "@angular/core";
+
+    export class Foo { }
     `),
     );
   });
+
+  it('should do nothing if the source file does not have a class', () => {
+    const sourceFileContent = `
+        export function foo() { }
+      `;
+
+    const project = new Project({ useInMemoryFileSystem: true });
+    const sourceFile = project.createSourceFile("foo.ts", sourceFileContent);
+
+    addImportToClass(sourceFile, "Component", "@angular/core");
+
+    expect(dedent(sourceFile.getText())).toBe(
+      dedent(`
+      export function foo() { }
+      `));
+  });
 });