fix: use ts compiler or babel depending on environment

Author: lmiller1990

lib/process.js

@@ -2,13 +2,15 @@ const { parse, compileTemplate } = require('@vue/compiler-sfc')
 const { transform } = require('@babel/core')
 const convertSourceMap = require('convert-source-map')
 const babelTransformer = require('babel-jest')
+const { transpileModule } = require('typescript')
 
 const generateSourceMap = require('./generate-source-map')
 const typescriptTransformer = require('./transformers/typescript')
 const coffeescriptTransformer = require('./transformers/coffee')
 const _processStyle = require('./process-style')
 const processCustomBlocks = require('./process-custom-blocks')
 const getVueJestConfig = require('./utils').getVueJestConfig
+const getTsJestConfig = require('./utils').getTsJestConfig
 const logResultErrors = require('./utils').logResultErrors
 const stripInlineSourceMap = require('./utils').stripInlineSourceMap
 const getCustomTransformer = require('./utils').getCustomTransformer
@@ -68,10 +70,19 @@ function processTemplate(template, filename, config) {
 
   logResultErrors(result)
 
-  const babelify = transform(result.code, { filename: 'file.js' })
+  const tsconfig = getTsJestConfig(config)
 
-  return {
-    code: babelify.code
+  if (tsconfig) {
+    // they are using TypeScript.
+    const { outputText } = transpileModule(result.code, { tsconfig })
+    return { code: outputText }
+  } else {
+    // babel
+    const babelify = transform(result.code, { filename: 'file.js' })
+
+    return {
+      code: babelify.code
+    }
   }
 }