chore(TypeScript): fix unit tests and coverage

src/parser/template.ts

@@ -1,10 +1,12 @@
 import * as _ from '../util/underscore'
 import * as path from 'path'
 import { anySeries } from '../util/promise'
-import * as fs from 'fs'
+import { stat, readFile } from 'fs'
 
-const statFileAsync = <(filepath: string) => Promise<object>>_.promisify(fs.stat)
-const readFileAsync = <(filepath: string, encoding: string) => Promise<string>>_.promisify(fs.readFile)
+export const fs = {
+  stat: _.promisify(stat) as ((filepath: string) => Promise<object>),
+  readFile: _.promisify(readFile) as ((filepath: string, encoding: string) => Promise<string>)
+}
 
 export async function resolve (filepath, root, options) {
   if (!path.extname(filepath)) {
@@ -15,7 +17,7 @@ export async function resolve (filepath, root, options) {
   const paths = root.map(root => path.resolve(root, filepath))
   return anySeries(paths, async path => {
     try {
-      await statFileAsync(path)
+      await fs.stat(path)
       return path
     } catch (e) {
       e.message = `${e.code}: Failed to lookup ${filepath} in: ${root}`
@@ -25,5 +27,5 @@ export async function resolve (filepath, root, options) {
 }
 
 export async function read (filepath): Promise<string> {
-  return readFileAsync(filepath, 'utf8')
+  return fs.readFile(filepath, 'utf8')
 }