add pathTransform test

Author: Ethan-Arrowood

src/cli.ts

@@ -102,7 +102,7 @@ And the user wants the outputs to be in MultiSchema/Out, then this code will be
   MultiSchema/Out/bar/fuzz/c.json
   MultiSchema/Out/bar/d.json
 */
-function pathTransform(o: string, i: string): string {
+export function pathTransform(o: string, i: string): string {
   const outPathList = o.split('/')
   const inPathList = i.split('/')
 
@@ -123,15 +123,6 @@ async function processDir(argIn: string, argOut: string | undefined, argv: Parti
         processFile(file, argOut, argv)
       } else {
         let outPath = pathTransform(argOut, file)
-        // const outPathList = argOut.split('/')
-        // const inPathList = file.split('/')
-
-        // const intersection = outPathList.filter(x => inPathList.includes(x))
-        // const difference = outPathList
-        //   .filter(x => !inPathList.includes(x))
-        //   .concat(inPathList.filter(x => !outPathList.includes(x)))
-
-        // let outPath = join(...intersection, ...difference)
         if (!isDir(dirname(outPath))) {
           _mkdirp.sync(dirname(outPath))
         }

test/testCLI.ts

@@ -2,6 +2,7 @@ import {serial as test} from 'ava'
 import {execSync} from 'child_process'
 import {readFileSync, unlinkSync, readdirSync, rmdirSync, existsSync, lstatSync} from 'fs'
 import {resolve, join} from 'path'
+import {pathTransform} from '../src/cli'
 
 export function run() {
   test('pipe in, pipe out', t => {
@@ -113,6 +114,15 @@ export function run() {
     })
     rmdirSync('./test/resources/MultiSchema2/out', {recursive: true})
   })
+
+  test('validate pathTransform function', t => {
+    const inputPaths = ['MultiSchema/foo/a.json', 'MultiSchema/bar/fuzz/c.json', 'MultiSchema/bar/d.json']
+    const outputPath = 'MultiSchema/Out'
+
+    t.is(pathTransform(outputPath, inputPaths[0]), 'MultiSchema/Out/foo/a.json')
+    t.is(pathTransform(outputPath, inputPaths[1]), 'MultiSchema/Out/bar/d.json')
+    t.is(pathTransform(outputPath, inputPaths[2]), 'MultiSchema/Out/bar/fuzz/c.json')
+  })
 }
 
 function getPaths(path: string, paths: string[] = []) {