From dfb348447a70618c2324414141c3c92e7c63d889 Mon Sep 17 00:00:00 2001
From: Jan Florian Dietrich <luhmann@users.noreply.github.com>
Date: Wed, 29 Mar 2017 19:09:23 +0200
Subject: [PATCH] Use "compilerOptions" from projects tsconfig for jest

* .. if file is present
* .. if file is valid json
* .. if compilerOptions are set in tsconfig.json
* .. fall back to old value in other cases
---
 .../config/jest/typescriptTransform.js        | 26 ++++++++++++++-----
 packages/react-scripts/package.json           |  1 +
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/packages/react-scripts/config/jest/typescriptTransform.js b/packages/react-scripts/config/jest/typescriptTransform.js
index f503b65b..b6ac285e 100644
--- a/packages/react-scripts/config/jest/typescriptTransform.js
+++ b/packages/react-scripts/config/jest/typescriptTransform.js
@@ -1,21 +1,33 @@
 // Copyright 2004-present Facebook. All Rights Reserved.
 
+const fs = require('fs');
 const tsc = require('typescript');
+const tsconfigPath = require('app-root-path').resolve('/tsconfig.json');
+
+let compilerConfig = {
+  module: tsc.ModuleKind.CommonJS,
+  jsx: tsc.JsxEmit.React,
+}
+
+if (fs.existsSync(tsconfigPath)) {
+  try {
+    const tsconfig = require(tsconfigPath);
+
+    if (tsconfig && tsconfig.compilerOptions) {
+      compilerConfig = tsconfig.compilerOptions;
+    }
+  } catch (e) { /* Do nothing - default is set */ }
+}
 
 module.exports = {
   process(src, path) {
     if (path.endsWith('.ts') || path.endsWith('.tsx')) {
       return tsc.transpile(
         src,
-        {
-          module: tsc.ModuleKind.CommonJS,
-          jsx: tsc.JsxEmit.React,
-        },
-        path,
-        []
+        compilerConfig,
+        path, []
       );
     }
     return src;
   },
 };
-
diff --git a/packages/react-scripts/package.json b/packages/react-scripts/package.json
index 33e4f867..3a42086c 100644
--- a/packages/react-scripts/package.json
+++ b/packages/react-scripts/package.json
@@ -24,6 +24,7 @@
     "react-scripts-ts": "./bin/react-scripts-ts.js"
   },
   "dependencies": {
+    "app-root-path": "^2.0.1",
     "autoprefixer": "6.7.2",
     "case-sensitive-paths-webpack-plugin": "1.1.4",
     "chalk": "1.1.3",