refactor(ios): simplify external xctest startup

Author: V3RON

.nx/version-plans/version-plan-1778676000000.md

@@ -0,0 +1,5 @@
+---
+__default__: patch
+---
+
+Harness on iOS can now start from an externally prepared `.xctestrun` and derived data directory, so you can run XCTest-based flows on hosted device infrastructure without rebuilding the agent on the runner.

packages/platform-ios/src/xctest-agent.ts

@@ -104,6 +104,11 @@ type SimulatorXCTestAgentCacheContext = Omit<
   'artifactName' | 'destinationKind' | 'schemaVersion' | 'xctestrunRelativePath'
 >;
 
+type ExternalXCTestConfiguration = {
+  derivedDataPath: string;
+  xctestrunFilePath: string;
+};
+
 export type XCTestAgentController = {
   prepare: () => Promise<void>;
   ensureStarted: () => Promise<void>;
@@ -177,6 +182,23 @@ const assertExternalXCTestRunFileExists = (filePath: string) => {
   );
 };
 
+const getExternalXCTestConfiguration = (
+  fallbackDerivedDataPath: string
+): ExternalXCTestConfiguration | null => {
+  const xctestrunFilePath = getExternalXCTestRunFilePath();
+
+  if (!xctestrunFilePath) {
+    return null;
+  }
+
+  assertExternalXCTestRunFileExists(xctestrunFilePath);
+
+  return {
+    derivedDataPath: getExternalDerivedDataPath() ?? fallbackDerivedDataPath,
+    xctestrunFilePath,
+  };
+};
+
 const getXCTestAgentBuildManifestPath = (derivedDataPath: string): string =>
   path.join(derivedDataPath, 'build-manifest.json');
 
@@ -908,6 +930,7 @@ export const createXCTestAgentController = (options: {
     'xcodebuild.log'
   );
   let preparedDerivedDataPath = getXCTestAgentDerivedDataPath(target.kind);
+  let preparedXCTestRunFilePath: string | null = null;
   let prepared = false;
   let agentProcess: Subprocess | null = null;
   let agentClient: ReturnType<typeof createXCTestAgentClient> | null = null;
@@ -943,20 +966,20 @@ export const createXCTestAgentController = (options: {
       return;
     }
 
-    const externalXCTestRunFilePath = getExternalXCTestRunFilePath();
-    if (externalXCTestRunFilePath) {
-      assertExternalXCTestRunFileExists(externalXCTestRunFilePath);
+    const externalXCTestConfiguration = getExternalXCTestConfiguration(
+      preparedDerivedDataPath
+    );
 
-      const externalDerivedDataPath = getExternalDerivedDataPath();
-      if (externalDerivedDataPath) {
-        preparedDerivedDataPath = externalDerivedDataPath;
-      }
+    if (externalXCTestConfiguration) {
+      preparedDerivedDataPath = externalXCTestConfiguration.derivedDataPath;
+      preparedXCTestRunFilePath =
+        externalXCTestConfiguration.xctestrunFilePath;
 
       prepared = true;
       xctestAgentLogger.info(
         'Using external XCTest run file for %s target: %s',
         target.kind,
-        externalXCTestRunFilePath
+        preparedXCTestRunFilePath
       );
       return;
     }
@@ -973,6 +996,7 @@ export const createXCTestAgentController = (options: {
     });
 
     preparedDerivedDataPath = buildResult.derivedDataPath;
+    preparedXCTestRunFilePath = null;
     prepared = true;
   };
 
@@ -992,19 +1016,14 @@ export const createXCTestAgentController = (options: {
       target.kind
     );
     xctestAgentLogger.debug('Using XCTest agent port %d', port);
-    const externalXCTestRunFilePath = getExternalXCTestRunFilePath();
-    let xcodebuildRunInputArgs: string[];
-
-    if (externalXCTestRunFilePath) {
-      xcodebuildRunInputArgs = ['-xctestrun', externalXCTestRunFilePath];
-    } else {
-      xcodebuildRunInputArgs = [
-        '-project',
-        getXCTestAgentProjectFilePath(),
-        '-scheme',
-        XCTEST_AGENT_SCHEME_NAME,
-      ];
-    }
+    const xcodebuildRunInputArgs = preparedXCTestRunFilePath
+      ? ['-xctestrun', preparedXCTestRunFilePath]
+      : [
+          '-project',
+          getXCTestAgentProjectFilePath(),
+          '-scheme',
+          XCTEST_AGENT_SCHEME_NAME,
+        ];
 
     const xcodebuildArgs = [
       'test-without-building',