feat(utils): loadPathAliases

Signed-off-by: Lexus Drumgold <unicornware@flexdevelopment.llc>

src/utils/__mocks__/load-compiler-options.ts

@@ -0,0 +1,18 @@
+/**
+ * @file Mock Utilities - loadCompilerOptions
+ * @module mlly/utils/mocks/loadCompilerOptions
+ */
+
+/**
+ * `loadCompilerOptions` module type.
+ */
+type Actual = typeof import('../load-compiler-options')
+
+/**
+ * `loadCompilerOptions` module.
+ *
+ * @const {Actual} actual
+ */
+const actual: Actual = await vi.importActual<Actual>('../load-compiler-options')
+
+export default vi.fn(actual.default)

src/utils/__tests__/load-path-aliases.spec.ts

@@ -0,0 +1,39 @@
+/**
+ * @file Unit Tests - loadPathAliases
+ * @module tsconfig-utils/utils/tests/unit/loadPathAliases
+ */
+
+import type { Spy } from '#tests/interfaces'
+import getTsconfigJson from '#tests/utils/get-tsconfig-json'
+import type { Paths } from '@flex-development/tsconfig-types'
+import loadCompilerOptions from '../load-compiler-options'
+import testSubject from '../load-path-aliases'
+
+vi.mock('../load-compiler-options')
+
+describe('unit:utils/loadPathAliases', () => {
+  let id: string
+  let loadCompilerOptionsMock: Spy<typeof loadCompilerOptions>
+
+  beforeAll(() => {
+    id = 'tsconfig.json'
+    loadCompilerOptionsMock =
+      loadCompilerOptions as unknown as typeof loadCompilerOptionsMock
+  })
+
+  it('should return Paths object', () => {
+    // Arrange
+    const paths: Paths = getTsconfigJson(id)!.compilerOptions!.paths!
+
+    // Act + Expect
+    expect(testSubject(id)).to.deep.equal(paths)
+  })
+
+  it('should return empty object if compilerOptions.paths is NIL', () => {
+    // Arrange
+    loadCompilerOptionsMock.mockReturnValueOnce({})
+
+    // Act + Expect
+    expect(testSubject(id)).to.deep.equal({})
+  })
+})

src/utils/index.ts

@@ -5,3 +5,4 @@
 
 export { default as loadCompilerOptions } from './load-compiler-options'
 export { default as loadTsconfig } from './load-tsconfig'
+export { default as loadPathAliases } from './load-path-aliases'

src/utils/load-path-aliases.ts

@@ -0,0 +1,26 @@
+/**
+ * @file Utilities - loadPathAliases
+ * @module tsconfig-utils/utils/loadPathAliases
+ */
+
+import type { LoadTsconfigOptions } from '#src/interfaces'
+import type { Paths } from '@flex-development/tsconfig-types'
+import type { URL } from 'node:url'
+import loadCompilerOptions from './load-compiler-options'
+
+/**
+ * Loads a [path alias configuration][1] from a [tsconfig][2] file.
+ *
+ * [1]: https://www.typescriptlang.org/tsconfig#paths
+ * [2]: https://www.typescriptlang.org/tsconfig
+ *
+ * @param {URL | string} id - Module id of tsconfig file
+ * @param {LoadTsconfigOptions} [options={}] - Tsconfig loading options
+ * @return {Paths} Path alias configuration object
+ */
+const loadPathAliases = (
+  id: URL | string,
+  options: LoadTsconfigOptions = {}
+): Paths => loadCompilerOptions(id, options).paths ?? {}
+
+export default loadPathAliases