From a2fef9cbfb2fb3d7dbbe5fde932babeb0eb81791 Mon Sep 17 00:00:00 2001
From: esvyridov <esvyridov@solvd.com>
Date: Wed, 11 Dec 2019 16:24:36 +0300
Subject: [PATCH 1/2] Support JSONC format for jsconfig.json

---
 packages/react-scripts/config/modules.js | 38 +++++++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/packages/react-scripts/config/modules.js b/packages/react-scripts/config/modules.js
index 38c95b91e44..a4112015e32 100644
--- a/packages/react-scripts/config/modules.js
+++ b/packages/react-scripts/config/modules.js
@@ -110,6 +110,10 @@ function getModules() {
   // Check if TypeScript is setup
   const hasTsConfig = fs.existsSync(paths.appTsConfig);
   const hasJsConfig = fs.existsSync(paths.appJsConfig);
+  const hasTsSetup = fs.existsSync(
+    path.join(paths.appNodeModules, 'typescript')
+  );
+  const isYarn = fs.existsSync(paths.yarnLockFile);
 
   if (hasTsConfig && hasJsConfig) {
     throw new Error(
@@ -130,7 +134,39 @@ function getModules() {
     // Otherwise we'll check if there is jsconfig.json
     // for non TS projects.
   } else if (hasJsConfig) {
-    config = require(paths.appJsConfig);
+    if (hasTsSetup) {
+      const ts = require(resolve.sync('typescript', {
+        basedir: paths.appNodeModules,
+      }));
+
+      config = ts.readConfigFile(paths.appTsConfig, ts.sys.readFile).config;
+    } else {
+      try {
+        config = require(paths.appJsConfig);
+      } catch (err) {
+        console.error(
+          chalk.bold.red(
+            `It looks like your jsconfig.json file has comments but ${chalk.bold(
+              'typescript'
+            )} is not installed.`,
+            `If you want to support JSONC you have to install ${chalk.bold(
+              'typescript'
+            )} as a dependency.`
+          )
+        );
+        console.log(
+          chalk.bold(
+            'Please install',
+            chalk.cyan.bold('typescript'),
+            'by running',
+            chalk.cyan.bold(
+              isYarn ? 'yarn add typescript' : 'npm install typescript'
+            ) + '.'
+          )
+        );
+        process.exit(1);
+      }
+    }
   }
 
   config = config || {};

From 2676656cf711ce7e0c8a63b5f56fa33e96866dcc Mon Sep 17 00:00:00 2001
From: esvyridov <esvyridov@solvd.com>
Date: Mon, 16 Dec 2019 22:05:05 +0300
Subject: [PATCH 2/2] Remove hasTsSetup, optimize error message

---
 packages/react-scripts/config/modules.js | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/packages/react-scripts/config/modules.js b/packages/react-scripts/config/modules.js
index a4112015e32..6a2e69a1de4 100644
--- a/packages/react-scripts/config/modules.js
+++ b/packages/react-scripts/config/modules.js
@@ -110,9 +110,6 @@ function getModules() {
   // Check if TypeScript is setup
   const hasTsConfig = fs.existsSync(paths.appTsConfig);
   const hasJsConfig = fs.existsSync(paths.appJsConfig);
-  const hasTsSetup = fs.existsSync(
-    path.join(paths.appNodeModules, 'typescript')
-  );
   const isYarn = fs.existsSync(paths.yarnLockFile);
 
   if (hasTsConfig && hasJsConfig) {
@@ -134,15 +131,19 @@ function getModules() {
     // Otherwise we'll check if there is jsconfig.json
     // for non TS projects.
   } else if (hasJsConfig) {
-    if (hasTsSetup) {
+    // Trying to parse jsconfig.json
+    // using TypeScript
+    try {
       const ts = require(resolve.sync('typescript', {
         basedir: paths.appNodeModules,
       }));
 
-      config = ts.readConfigFile(paths.appTsConfig, ts.sys.readFile).config;
-    } else {
+      config = ts.readConfigFile(paths.appJsConfig, ts.sys.readFile).config;
+    } catch (err) {
+      // Trying to parse jsconfig.json
       try {
         config = require(paths.appJsConfig);
+        // If error we assume jsconfig.json has comments
       } catch (err) {
         console.error(
           chalk.bold.red(
@@ -160,7 +161,7 @@ function getModules() {
             chalk.cyan.bold('typescript'),
             'by running',
             chalk.cyan.bold(
-              isYarn ? 'yarn add typescript' : 'npm install typescript'
+              (isYarn ? 'yarn add' : 'npm install') + ' typescript'
             ) + '.'
           )
         );