fix: do not require ts-jest and typescript

Author: lmiller1990

lib/utils.js

@@ -1,5 +1,6 @@
 const constants = require('./constants')
 const loadPartialConfig = require('@babel/core').loadPartialConfig
+const { resolveSync: resolveTsConfigSync } = require('tsconfig')
 const chalk = require('chalk')
 const path = require('path')
 const fs = require('fs')
@@ -64,6 +65,11 @@ const getBabelOptions = function loadBabelOptions(filename, options = {}) {
 }
 
 const getTsJestConfig = function getTsJestConfig(config) {
+  const isUsingTs = resolveTsConfigSync(process.cwd())
+  if (!isUsingTs) {
+    return null
+  }
+
   const createTransformer = require('ts-jest').createTransformer
   const tr = createTransformer()
   const configSet = tr.configsFor(config)

package.json

@@ -80,7 +80,7 @@
     "chalk": "^2.1.0",
     "convert-source-map": "^1.6.0",
     "extract-from-css": "^0.4.4",
-    "ts-jest": "^24.0.0"
+    "tsconfig": "^7.0.0"
   },
   "repository": {
     "type": "git",

yarn.lock

@@ -1076,6 +1076,16 @@
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/@types/stack-utils/-/stack-utils-1.0.1.tgz#0a851d3bd96498fa25c33ab7278ed3bd65f06c3e"
 
+"@types/strip-bom@^3.0.0":
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/@types/strip-bom/-/strip-bom-3.0.0.tgz#14a8ec3956c2e81edb7520790aecf21c290aebd2"
+  integrity sha1-FKjsOVbC6B7bdSB5CuzyHCkK69I=
+
+"@types/strip-json-comments@0.0.30":
+  version "0.0.30"
+  resolved "https://registry.yarnpkg.com/@types/strip-json-comments/-/strip-json-comments-0.0.30.tgz#9aa30c04db212a9a0649d6ae6fd50accc40748a1"
+  integrity sha512-7NQmHra/JILCd1QqpSzl8+mJRc8ZHz3uDm8YV1Ks9IhK0epEiTw8aIErbvH9PI+6XbqhyIQy3462nEsn7UVzjQ==
+
 "@types/yargs-parser@*":
   version "15.0.0"
   resolved "https://registry.yarnpkg.com/@types/yargs-parser/-/yargs-parser-15.0.0.tgz#cb3f9f741869e20cce330ffbeb9271590483882d"
@@ -7758,7 +7768,7 @@ strip-indent@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/strip-indent/-/strip-indent-2.0.0.tgz#5ef8db295d01e6ed6cbf7aab96998d7822527b68"
 
-strip-json-comments@^2.0.1, strip-json-comments@~2.0.1:
+strip-json-comments@^2.0.0, strip-json-comments@^2.0.1, strip-json-comments@~2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/strip-json-comments/-/strip-json-comments-2.0.1.tgz#3c531942e908c2697c0ec344858c286c7ca0a60a"
 
@@ -8001,6 +8011,16 @@ ts-jest@^24.0.0:
     semver "^5.5"
     yargs-parser "10.x"
 
+tsconfig@^7.0.0:
+  version "7.0.0"
+  resolved "https://registry.yarnpkg.com/tsconfig/-/tsconfig-7.0.0.tgz#84538875a4dc216e5c4a5432b3a4dec3d54e91b7"
+  integrity sha512-vZXmzPrL+EmC4T/4rVlT2jNVMWCi/O4DIiSj3UHg1OE5kCKbk4mfrXc6dZksLgRM/TZlKnousKH9bbTazUWRRw==
+  dependencies:
+    "@types/strip-bom" "^3.0.0"
+    "@types/strip-json-comments" "0.0.30"
+    strip-bom "^3.0.0"
+    strip-json-comments "^2.0.0"
+
 tslib@^1.10.0, tslib@^1.9.0:
   version "1.11.1"
   resolved "https://registry.yarnpkg.com/tslib/-/tslib-1.11.1.tgz#eb15d128827fbee2841549e171f45ed338ac7e35"