Improve xcode version mismatch messaging

Summary:
This runs in a very hot loop (which I will change shortly)

However, there's also some simplification that we can do here:
- Only look for `Simulator.app` processes instead of all the processes. This limits the amount of string comparison to do. If there's a `Simulator.app` running, then we know a sim is running for that Xcode.
- Use piping to extract the launch path of the process, instead of then regex'ing this out.
- Use a simpler substring match to determine if paths have a different start.

Reviewed By: passy

Differential Revision: D33891296

fbshipit-source-id: e37d5f260fc6c6113be9c5268b7c8cffb4057b9a

desktop/flipper-server-core/src/devices/ios/__tests__/iOSDevice.node.tsx

@@ -7,7 +7,7 @@
  * @format
  */
 
-import {parseXcodeFromCoreSimPath} from '../iOSDeviceManager';
+import {checkXcodeVersionMismatch} from '../iOSDeviceManager';
 import {getLogger} from 'flipper-common';
 import {IOSBridge} from '../IOSBridge';
 import {FlipperServerImpl} from '../../../FlipperServerImpl';
@@ -36,46 +36,28 @@ afterEach(() => {
   setFlipperServerConfig(undefined);
 });
 
-const standardCoresimulatorLog =
+test('test checkXcodeVersionMismatch with correct Simulator.app', () => {
-  'username            1264   0.0  0.1  5989740  41648   ??  Ss    2:23PM   0:12.92 /Applications/Xcode_12.4.0_fb.app/Contents/Developer/Platforms/iPhoneOS.platform/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/Resources/RuntimeRoot/usr/libexec/mobileassetd';
+  const invalidVersion = checkXcodeVersionMismatch(
-
+    [
-const nonStandardCoresimulatorLog =
+      '/Applications/Xcode.app/Contents/Developer/Applications/Simulator.app/Contents/MacOS/Simulator',
-  'username            1264   0.0  0.1  5989740  41648   ??  Ss    2:23PM   0:12.92 /Some/Random/Path/Xcode_12.4.0_fb.app/Contents/Developer/Platforms/iPhoneOS.platform/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/Resources/RuntimeRoot/usr/libexec/mobileassetd';
+    ],
-
+    '/Applications/Xcode.app/Contents/Developer',
-const nonStandardSpecialCharacterAphanumericCoresimulatorLog =
+  );
-  'username            1264   0.0  0.1  5989740  41648   ??  Ss    2:23PM   0:12.92 /Some_R@d0m/Path-3455355/path(2)+connection/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS.simruntime/Contents/Resources/RuntimeRoot/usr/libexec/mobileassetd';
+  expect(invalidVersion).toEqual(undefined);
-
-test('test parseXcodeFromCoreSimPath from non standard locations', () => {
-  const match = parseXcodeFromCoreSimPath(nonStandardCoresimulatorLog);
-  expect(match && match.length > 0).toBeTruthy();
-  expect(
-    // @ts-ignore the null and non zero lenght check for match is already done above
-    match[0],
-  ).toEqual('/Some/Random/Path/Xcode_12.4.0_fb.app/Contents/Developer');
 });
 
-test('test parseXcodeFromCoreSimPath from non standard alphanumeric special character locations', () => {
+test('test checkXcodeVersionMismatch with an incorrect Simulator.app', () => {
-  const match = parseXcodeFromCoreSimPath(
+  const invalidVersion = checkXcodeVersionMismatch(
-    nonStandardSpecialCharacterAphanumericCoresimulatorLog,
+    [
+      '/Applications/Xcode_Incorrect.app/Contents/Developer/Applications/Simulator.app/Contents/MacOS/Simulator',
+    ],
+    '/Applications/Xcode.app/Contents/Developer',
   );
-  expect(match && match.length > 0).toBeTruthy();
+  expect(invalidVersion).toEqual(
-  expect(
+    '/Applications/Xcode_Incorrect.app/Contents/Developer',
-    // @ts-ignore the null and non zero lenght check for match is already done above
-    match[0],
-  ).toEqual(
-    '/Some_R@d0m/Path-3455355/path(2)+connection/Xcode.app/Contents/Developer',
   );
 });
 
-test('test parseXcodeFromCoreSimPath from standard locations', () => {
-  const match = parseXcodeFromCoreSimPath(standardCoresimulatorLog);
-  expect(match && match.length > 0).toBeTruthy();
-  expect(
-    // @ts-ignore the null and non zero lenght check for match is already done above
-    match[0],
-  ).toEqual('/Applications/Xcode_12.4.0_fb.app/Contents/Developer');
-});
-
 test('test getAllPromisesForQueryingDevices when xcode detected', () => {
   const flipperServer = new FlipperServerImpl(
     getFlipperServerConfig(),

desktop/flipper-server-core/src/devices/ios/iOSDeviceManager.tsx

@@ -231,21 +231,27 @@ export class IOSDeviceManager {
     try {
       let {stdout: xcodeCLIVersion} = await exec('xcode-select -p');
       xcodeCLIVersion = xcodeCLIVersion!.toString().trim();
-      const {stdout} = await exec('ps aux | grep CoreSimulator');
+      const {stdout} = await exec(
-      for (const line of stdout!.toString().split('\n')) {
+        "pgrep Simulator | xargs ps | grep Simulator.app | awk '{print $NF}'",
-        const match = parseXcodeFromCoreSimPath(line);
+      );
-        const runningVersion =
+      for (const runningSimulatorApp of stdout!.toString().split('\n')) {
-          match && match.length > 0 ? match[0].trim() : null;
+        if (!runningSimulatorApp) {
-        if (runningVersion && runningVersion !== xcodeCLIVersion) {
+          continue;
-          const errorMessage = `Xcode version mismatch: Simulator is running from "${runningVersion}" while Xcode CLI is "${xcodeCLIVersion}". Running "xcode-select --switch ${runningVersion}" can fix this. For example: "sudo xcode-select -s /Applications/Xcode.app/Contents/Developer"`;
-          this.flipperServer.emit('notification', {
-            type: 'error',
-            title: 'Xcode version mismatch',
-            description: '' + errorMessage,
-          });
-          this.xcodeVersionMismatchFound = true;
-          break;
         }
+        if (runningSimulatorApp.startsWith(xcodeCLIVersion)) {
+          continue;
+        }
+        const runningVersion =
+          runningSimulatorApp.split('/Contents/Developer')[0] +
+          '/Contents/Developer';
+        const errorMessage = `Xcode version mismatch: Simulator is running from "${runningVersion}" while Xcode CLI is "${xcodeCLIVersion}". Running "xcode-select --switch ${runningVersion}" can fix this. For example: "sudo xcode-select -s /Applications/Xcode.app/Contents/Developer"`;
+        this.flipperServer.emit('notification', {
+          type: 'error',
+          title: 'Xcode version mismatch',
+          description: '' + errorMessage,
+        });
+        this.xcodeVersionMismatchFound = true;
+        break;
       }
     } catch (e) {
       console.error('Failed to determine Xcode version:', e);
@@ -253,15 +259,28 @@ export class IOSDeviceManager {
   }
 }
 
+export function checkXcodeVersionMismatch(
+  runningSimulatorApps: Array<string>,
+  xcodeCLIVersion: string,
+): string | undefined {
+  for (const runningSimulatorApp of runningSimulatorApps) {
+    if (!runningSimulatorApp) {
+      continue;
+    }
+    if (runningSimulatorApp.startsWith(xcodeCLIVersion)) {
+      continue;
+    }
+    return (
+      runningSimulatorApp.split('/Contents/Developer')[0] +
+      '/Contents/Developer'
+    );
+  }
+  return undefined;
+}
+
 function getActiveDevices(
   idbPath: string,
   isPhysicalDeviceEnabled: boolean,
 ): Promise<Array<IOSDeviceParams>> {
   return new IDBBridge(idbPath, isPhysicalDeviceEnabled).getActiveDevices(true);
 }
-
-export function parseXcodeFromCoreSimPath(
-  line: string,
-): RegExpMatchArray | null {
-  return line.match(/\/[\/\w@)(\-\+]*\/Xcode[^/]*\.app\/Contents\/Developer/);
-}