From b1e2d1cb1964aa32b8ef9cecfcf5ce9a3f49a3da Mon Sep 17 00:00:00 2001
From: Lawrence Chen <lawrencecchen@users.noreply.github.com>
Date: Wed, 18 Mar 2026 01:40:04 -0700
Subject: [PATCH 1/6] Pass display harness manifest path into UI test

---
 .github/workflows/ci.yml                             | 1 +
 .github/workflows/test-e2e.yml                       | 1 +
 cmuxUITests/DisplayResolutionRegressionUITests.swift | 9 +++++----
 3 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e93274d3..04849f71 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -513,6 +513,7 @@ jobs:
           CMUX_UI_TEST_DISPLAY_START_PATH="$START_PATH" \
           CMUX_UI_TEST_DISPLAY_DONE_PATH="$DONE_PATH" \
           CMUX_UI_TEST_DISPLAY_LOG_PATH="$LOG_PATH" \
+          CMUX_UI_TEST_DISPLAY_HARNESS_MANIFEST_PATH="$MANIFEST_PATH" \
           xcodebuild -project GhosttyTabs.xcodeproj -scheme cmux -configuration Debug \
             -clonedSourcePackagesDirPath "$SOURCE_PACKAGES_DIR" \
             -disableAutomaticPackageResolution \
diff --git a/.github/workflows/test-e2e.yml b/.github/workflows/test-e2e.yml
index 6f651725..c56f833e 100644
--- a/.github/workflows/test-e2e.yml
+++ b/.github/workflows/test-e2e.yml
@@ -257,6 +257,7 @@ jobs:
               CMUX_UI_TEST_DISPLAY_START_PATH="$START_PATH"
               CMUX_UI_TEST_DISPLAY_DONE_PATH="$DONE_PATH"
               CMUX_UI_TEST_DISPLAY_LOG_PATH="$LOG_PATH"
+              CMUX_UI_TEST_DISPLAY_HARNESS_MANIFEST_PATH="$MANIFEST_PATH"
             )
           fi
 
diff --git a/cmuxUITests/DisplayResolutionRegressionUITests.swift b/cmuxUITests/DisplayResolutionRegressionUITests.swift
index 579ae221..f508e09f 100644
--- a/cmuxUITests/DisplayResolutionRegressionUITests.swift
+++ b/cmuxUITests/DisplayResolutionRegressionUITests.swift
@@ -2,7 +2,7 @@ import XCTest
 import Foundation
 
 final class DisplayResolutionRegressionUITests: XCTestCase {
-    private let displayHarnessManifestPath = "/tmp/cmux-ui-test-display-harness.json"
+    private let defaultDisplayHarnessManifestPath = "/tmp/cmux-ui-test-display-harness.json"
     private var launchTag = ""
     private var diagnosticsPath = ""
     private var displayReadyPath = ""
@@ -118,7 +118,7 @@ final class DisplayResolutionRegressionUITests: XCTestCase {
 
     private func prepareDisplayHarnessIfNeeded() throws {
         let env = ProcessInfo.processInfo.environment
-        if let externalHarness = loadExternalHarnessFromEnvironment(env) ?? loadExternalHarnessFromManifest() {
+        if let externalHarness = loadExternalHarnessFromEnvironment(env) ?? loadExternalHarnessFromManifest(env) {
             displayReadyPath = externalHarness.readyPath
             displayIDPath = externalHarness.displayIDPath
             displayStartPath = externalHarness.startPath
@@ -150,8 +150,9 @@ final class DisplayResolutionRegressionUITests: XCTestCase {
         )
     }
 
-    private func loadExternalHarnessFromManifest() -> ExternalDisplayHarness? {
-        let manifestURL = URL(fileURLWithPath: displayHarnessManifestPath)
+    private func loadExternalHarnessFromManifest(_ env: [String: String]) -> ExternalDisplayHarness? {
+        let manifestPath = env["CMUX_UI_TEST_DISPLAY_HARNESS_MANIFEST_PATH"] ?? defaultDisplayHarnessManifestPath
+        let manifestURL = URL(fileURLWithPath: manifestPath)
         guard let data = try? Data(contentsOf: manifestURL) else {
             return nil
         }

From 95cd26c0b6a850892ae68c172339ca77025e15af Mon Sep 17 00:00:00 2001
From: Lawrence Chen <lawrencecchen@users.noreply.github.com>
Date: Wed, 18 Mar 2026 01:46:32 -0700
Subject: [PATCH 2/6] Restore stable display harness manifest path

---
 .github/workflows/ci.yml       | 2 +-
 .github/workflows/test-e2e.yml | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 04849f71..fc905d66 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -473,7 +473,7 @@ jobs:
           START_PATH="${PREFIX}.start"
           DONE_PATH="${PREFIX}.done"
           LOG_PATH="${PREFIX}.log"
-          MANIFEST_PATH="${HARNESS_DIR}/cmux-ui-test-display-harness.json"
+          MANIFEST_PATH="/tmp/cmux-ui-test-display-harness.json"
 
           rm -f "$READY_PATH" "$DISPLAY_ID_PATH" "$START_PATH" "$DONE_PATH" "$LOG_PATH" "$MANIFEST_PATH"
 
diff --git a/.github/workflows/test-e2e.yml b/.github/workflows/test-e2e.yml
index c56f833e..7e5105ae 100644
--- a/.github/workflows/test-e2e.yml
+++ b/.github/workflows/test-e2e.yml
@@ -216,7 +216,7 @@ jobs:
             START_PATH="${PREFIX}.start"
             DONE_PATH="${PREFIX}.done"
             LOG_PATH="${PREFIX}.log"
-            MANIFEST_PATH="${HARNESS_DIR}/cmux-ui-test-display-harness.json"
+            MANIFEST_PATH="/tmp/cmux-ui-test-display-harness.json"
 
             rm -f "$READY_PATH" "$DISPLAY_ID_PATH" "$START_PATH" "$DONE_PATH" "$LOG_PATH" "$MANIFEST_PATH"
 

From 1c6d5568f7a25d3e4a3c98b848f6bb1b89e5e6ba Mon Sep 17 00:00:00 2001
From: Lawrence Chen <lawrencecchen@users.noreply.github.com>
Date: Wed, 18 Mar 2026 03:13:23 -0700
Subject: [PATCH 3/6] Move display harness rendezvous files to /tmp

---
 .github/workflows/ci.yml       | 4 +---
 .github/workflows/test-e2e.yml | 4 +---
 2 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fc905d66..d1fdec6d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -465,9 +465,7 @@ jobs:
         run: |
           set -euo pipefail
           SOURCE_PACKAGES_DIR="$PWD/.ci-source-packages"
-          HARNESS_DIR="${RUNNER_TEMP}/cmux-display-churn-${GITHUB_RUN_ID}-${GITHUB_RUN_ATTEMPT}"
-          mkdir -p "$HARNESS_DIR"
-          PREFIX="${HARNESS_DIR}/cmux-display-churn"
+          PREFIX="/tmp/cmux-display-churn-${GITHUB_RUN_ID}-${GITHUB_RUN_ATTEMPT}"
           READY_PATH="${PREFIX}.ready"
           DISPLAY_ID_PATH="${PREFIX}.id"
           START_PATH="${PREFIX}.start"
diff --git a/.github/workflows/test-e2e.yml b/.github/workflows/test-e2e.yml
index 7e5105ae..e538b6c5 100644
--- a/.github/workflows/test-e2e.yml
+++ b/.github/workflows/test-e2e.yml
@@ -208,9 +208,7 @@ jobs:
           DISPLAY_ENV_PREFIX=()
 
           if [ "$TEST_FILTER" = "DisplayResolutionRegressionUITests" ]; then
-            HARNESS_DIR="${RUNNER_TEMP}/cmux-display-churn-${{ github.run_id }}-${{ github.run_attempt }}"
-            mkdir -p "$HARNESS_DIR"
-            PREFIX="${HARNESS_DIR}/cmux-display-churn"
+            PREFIX="/tmp/cmux-display-churn-${{ github.run_id }}-${{ github.run_attempt }}"
             READY_PATH="${PREFIX}.ready"
             DISPLAY_ID_PATH="${PREFIX}.id"
             START_PATH="${PREFIX}.start"

From 7fb1f50966def2a4d37a7f7c9c62f967b28c4592 Mon Sep 17 00:00:00 2001
From: Lawrence Chen <lawrencecchen@users.noreply.github.com>
Date: Wed, 18 Mar 2026 03:22:04 -0700
Subject: [PATCH 4/6] Launch display helper from inside the UI test sandbox

---
 .github/workflows/ci.yml                      | 47 ++-----------------
 .github/workflows/test-e2e.yml                | 47 ++-----------------
 .../DisplayResolutionRegressionUITests.swift  | 28 ++++++++---
 3 files changed, 28 insertions(+), 94 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d1fdec6d..8018dbf9 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -465,53 +465,12 @@ jobs:
         run: |
           set -euo pipefail
           SOURCE_PACKAGES_DIR="$PWD/.ci-source-packages"
-          PREFIX="/tmp/cmux-display-churn-${GITHUB_RUN_ID}-${GITHUB_RUN_ATTEMPT}"
-          READY_PATH="${PREFIX}.ready"
-          DISPLAY_ID_PATH="${PREFIX}.id"
-          START_PATH="${PREFIX}.start"
-          DONE_PATH="${PREFIX}.done"
-          LOG_PATH="${PREFIX}.log"
-          MANIFEST_PATH="/tmp/cmux-ui-test-display-harness.json"
-
-          rm -f "$READY_PATH" "$DISPLAY_ID_PATH" "$START_PATH" "$DONE_PATH" "$LOG_PATH" "$MANIFEST_PATH"
+          HELPER_PATH="/tmp/create-virtual-display"
 
           clang -framework Foundation -framework CoreGraphics \
-            -o /tmp/create-virtual-display scripts/create-virtual-display.m
+            -o "$HELPER_PATH" scripts/create-virtual-display.m
 
-          /tmp/create-virtual-display \
-            --modes 1920x1080,1728x1117,1600x900,1440x810 \
-            --ready-path "$READY_PATH" \
-            --display-id-path "$DISPLAY_ID_PATH" \
-            --start-path "$START_PATH" \
-            --done-path "$DONE_PATH" \
-            --iterations 40 \
-            --interval-ms 40 \
-            >"$LOG_PATH" 2>&1 &
-          VDISPLAY_PID=$!
-          trap 'kill "$VDISPLAY_PID" >/dev/null 2>&1 || true; rm -f "$MANIFEST_PATH"' EXIT
-
-          for _ in {1..120}; do
-            [ -f "$READY_PATH" ] && break
-            sleep 0.25
-          done
-          [ -f "$READY_PATH" ] || {
-            echo "Display harness failed to start" >&2
-            cat "$LOG_PATH" >&2 || true
-            exit 1
-          }
-
-          cat >"$MANIFEST_PATH" <<EOF
-          {"readyPath":"$READY_PATH","displayIDPath":"$DISPLAY_ID_PATH","startPath":"$START_PATH","donePath":"$DONE_PATH","logPath":"$LOG_PATH"}
-          EOF
-          echo "Display harness manifest: $MANIFEST_PATH"
-          cat "$MANIFEST_PATH"
-
-          CMUX_UI_TEST_DISPLAY_READY_PATH="$READY_PATH" \
-          CMUX_UI_TEST_DISPLAY_ID_PATH="$DISPLAY_ID_PATH" \
-          CMUX_UI_TEST_DISPLAY_START_PATH="$START_PATH" \
-          CMUX_UI_TEST_DISPLAY_DONE_PATH="$DONE_PATH" \
-          CMUX_UI_TEST_DISPLAY_LOG_PATH="$LOG_PATH" \
-          CMUX_UI_TEST_DISPLAY_HARNESS_MANIFEST_PATH="$MANIFEST_PATH" \
+          CMUX_UI_TEST_DISPLAY_HELPER_BINARY_PATH="$HELPER_PATH" \
           xcodebuild -project GhosttyTabs.xcodeproj -scheme cmux -configuration Debug \
             -clonedSourcePackagesDirPath "$SOURCE_PACKAGES_DIR" \
             -disableAutomaticPackageResolution \
diff --git a/.github/workflows/test-e2e.yml b/.github/workflows/test-e2e.yml
index e538b6c5..2fc23e61 100644
--- a/.github/workflows/test-e2e.yml
+++ b/.github/workflows/test-e2e.yml
@@ -208,54 +208,13 @@ jobs:
           DISPLAY_ENV_PREFIX=()
 
           if [ "$TEST_FILTER" = "DisplayResolutionRegressionUITests" ]; then
-            PREFIX="/tmp/cmux-display-churn-${{ github.run_id }}-${{ github.run_attempt }}"
-            READY_PATH="${PREFIX}.ready"
-            DISPLAY_ID_PATH="${PREFIX}.id"
-            START_PATH="${PREFIX}.start"
-            DONE_PATH="${PREFIX}.done"
-            LOG_PATH="${PREFIX}.log"
-            MANIFEST_PATH="/tmp/cmux-ui-test-display-harness.json"
-
-            rm -f "$READY_PATH" "$DISPLAY_ID_PATH" "$START_PATH" "$DONE_PATH" "$LOG_PATH" "$MANIFEST_PATH"
+            HELPER_PATH="/tmp/create-virtual-display"
 
             clang -framework Foundation -framework CoreGraphics \
-              -o /tmp/create-virtual-display scripts/create-virtual-display.m
-
-            /tmp/create-virtual-display \
-              --modes 1920x1080,1728x1117,1600x900,1440x810 \
-              --ready-path "$READY_PATH" \
-              --display-id-path "$DISPLAY_ID_PATH" \
-              --start-path "$START_PATH" \
-              --done-path "$DONE_PATH" \
-              --iterations 40 \
-              --interval-ms 40 \
-              >"$LOG_PATH" 2>&1 &
-            DISPLAY_VDISPLAY_PID=$!
-            trap 'kill "${DISPLAY_VDISPLAY_PID:-}" >/dev/null 2>&1 || true; rm -f "$MANIFEST_PATH"' EXIT
-
-            for _ in {1..120}; do
-              [ -f "$READY_PATH" ] && break
-              sleep 0.25
-            done
-            [ -f "$READY_PATH" ] || {
-              echo "Display harness failed to start" >&2
-              cat "$LOG_PATH" >&2 || true
-              exit 1
-            }
-
-            cat >"$MANIFEST_PATH" <<EOF
-          {"readyPath":"$READY_PATH","displayIDPath":"$DISPLAY_ID_PATH","startPath":"$START_PATH","donePath":"$DONE_PATH","logPath":"$LOG_PATH"}
-          EOF
-            echo "Display harness manifest: $MANIFEST_PATH"
-            cat "$MANIFEST_PATH"
+              -o "$HELPER_PATH" scripts/create-virtual-display.m
 
             DISPLAY_ENV_PREFIX=(
-              CMUX_UI_TEST_DISPLAY_READY_PATH="$READY_PATH"
-              CMUX_UI_TEST_DISPLAY_ID_PATH="$DISPLAY_ID_PATH"
-              CMUX_UI_TEST_DISPLAY_START_PATH="$START_PATH"
-              CMUX_UI_TEST_DISPLAY_DONE_PATH="$DONE_PATH"
-              CMUX_UI_TEST_DISPLAY_LOG_PATH="$LOG_PATH"
-              CMUX_UI_TEST_DISPLAY_HARNESS_MANIFEST_PATH="$MANIFEST_PATH"
+              CMUX_UI_TEST_DISPLAY_HELPER_BINARY_PATH="$HELPER_PATH"
             )
           fi
 
diff --git a/cmuxUITests/DisplayResolutionRegressionUITests.swift b/cmuxUITests/DisplayResolutionRegressionUITests.swift
index f508e09f..a504c634 100644
--- a/cmuxUITests/DisplayResolutionRegressionUITests.swift
+++ b/cmuxUITests/DisplayResolutionRegressionUITests.swift
@@ -19,14 +19,17 @@ final class DisplayResolutionRegressionUITests: XCTestCase {
         continueAfterFailure = false
 
         let token = UUID().uuidString
+        let tempPrefix = FileManager.default.temporaryDirectory
+            .appendingPathComponent("cmux-ui-test-display-\(token)")
+            .path
         launchTag = "ui-tests-display-resolution-\(token.prefix(8))"
         diagnosticsPath = "/tmp/cmux-ui-test-display-churn-\(token).json"
-        displayReadyPath = "/tmp/cmux-ui-test-display-ready-\(token)"
-        displayIDPath = "/tmp/cmux-ui-test-display-id-\(token)"
-        displayStartPath = "/tmp/cmux-ui-test-display-start-\(token)"
-        displayDonePath = "/tmp/cmux-ui-test-display-done-\(token)"
-        helperBinaryPath = "/tmp/cmux-ui-test-display-helper-\(token)"
-        helperLogPath = "/tmp/cmux-ui-test-display-helper-\(token).log"
+        displayReadyPath = "\(tempPrefix).ready"
+        displayIDPath = "\(tempPrefix).id"
+        displayStartPath = "\(tempPrefix).start"
+        displayDonePath = "\(tempPrefix).done"
+        helperBinaryPath = "\(tempPrefix)-helper"
+        helperLogPath = "\(tempPrefix)-helper.log"
 
         removeTestArtifacts()
     }
@@ -118,6 +121,11 @@ final class DisplayResolutionRegressionUITests: XCTestCase {
 
     private func prepareDisplayHarnessIfNeeded() throws {
         let env = ProcessInfo.processInfo.environment
+        if let helperBinaryPath = loadPrebuiltHelperBinaryPath(env) {
+            self.helperBinaryPath = helperBinaryPath
+            try launchDisplayHelper()
+            return
+        }
         if let externalHarness = loadExternalHarnessFromEnvironment(env) ?? loadExternalHarnessFromManifest(env) {
             displayReadyPath = externalHarness.readyPath
             displayIDPath = externalHarness.displayIDPath
@@ -133,6 +141,14 @@ final class DisplayResolutionRegressionUITests: XCTestCase {
         try launchDisplayHelper()
     }
 
+    private func loadPrebuiltHelperBinaryPath(_ env: [String: String]) -> String? {
+        guard let helperBinaryPath = env["CMUX_UI_TEST_DISPLAY_HELPER_BINARY_PATH"],
+              !helperBinaryPath.isEmpty else {
+            return nil
+        }
+        return helperBinaryPath
+    }
+
     private func loadExternalHarnessFromEnvironment(_ env: [String: String]) -> ExternalDisplayHarness? {
         guard let readyPath = env["CMUX_UI_TEST_DISPLAY_READY_PATH"], !readyPath.isEmpty,
               let displayIDPath = env["CMUX_UI_TEST_DISPLAY_ID_PATH"], !displayIDPath.isEmpty,

From fbe209cb33daf1007087f11068b85a32e06c04e8 Mon Sep 17 00:00:00 2001
From: Lawrence Chen <lawrencecchen@users.noreply.github.com>
Date: Wed, 18 Mar 2026 03:30:32 -0700
Subject: [PATCH 5/6] Read the prebuilt display helper path from the harness
 manifest

---
 .github/workflows/ci.yml                      |  9 ++++-
 .github/workflows/test-e2e.yml                | 10 ++++--
 .../DisplayResolutionRegressionUITests.swift  | 33 ++++++++++++++-----
 3 files changed, 39 insertions(+), 13 deletions(-)

diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8018dbf9..78dea457 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -466,11 +466,18 @@ jobs:
           set -euo pipefail
           SOURCE_PACKAGES_DIR="$PWD/.ci-source-packages"
           HELPER_PATH="/tmp/create-virtual-display"
+          MANIFEST_PATH="/tmp/cmux-ui-test-display-harness.json"
+
+          rm -f "$MANIFEST_PATH"
+          trap 'rm -f "$MANIFEST_PATH"' EXIT
 
           clang -framework Foundation -framework CoreGraphics \
             -o "$HELPER_PATH" scripts/create-virtual-display.m
 
-          CMUX_UI_TEST_DISPLAY_HELPER_BINARY_PATH="$HELPER_PATH" \
+          cat >"$MANIFEST_PATH" <<EOF
+          {"helperBinaryPath":"$HELPER_PATH"}
+          EOF
+
           xcodebuild -project GhosttyTabs.xcodeproj -scheme cmux -configuration Debug \
             -clonedSourcePackagesDirPath "$SOURCE_PACKAGES_DIR" \
             -disableAutomaticPackageResolution \
diff --git a/.github/workflows/test-e2e.yml b/.github/workflows/test-e2e.yml
index 2fc23e61..9e06603e 100644
--- a/.github/workflows/test-e2e.yml
+++ b/.github/workflows/test-e2e.yml
@@ -209,13 +209,17 @@ jobs:
 
           if [ "$TEST_FILTER" = "DisplayResolutionRegressionUITests" ]; then
             HELPER_PATH="/tmp/create-virtual-display"
+            MANIFEST_PATH="/tmp/cmux-ui-test-display-harness.json"
+
+            rm -f "$MANIFEST_PATH"
+            trap 'rm -f "$MANIFEST_PATH"' EXIT
 
             clang -framework Foundation -framework CoreGraphics \
               -o "$HELPER_PATH" scripts/create-virtual-display.m
 
-            DISPLAY_ENV_PREFIX=(
-              CMUX_UI_TEST_DISPLAY_HELPER_BINARY_PATH="$HELPER_PATH"
-            )
+            cat >"$MANIFEST_PATH" <<EOF
+            {"helperBinaryPath":"$HELPER_PATH"}
+            EOF
           fi
 
           # Start recording right before the test (after build/resolve).
diff --git a/cmuxUITests/DisplayResolutionRegressionUITests.swift b/cmuxUITests/DisplayResolutionRegressionUITests.swift
index a504c634..1cc5aecf 100644
--- a/cmuxUITests/DisplayResolutionRegressionUITests.swift
+++ b/cmuxUITests/DisplayResolutionRegressionUITests.swift
@@ -127,10 +127,23 @@ final class DisplayResolutionRegressionUITests: XCTestCase {
             return
         }
         if let externalHarness = loadExternalHarnessFromEnvironment(env) ?? loadExternalHarnessFromManifest(env) {
-            displayReadyPath = externalHarness.readyPath
-            displayIDPath = externalHarness.displayIDPath
-            displayStartPath = externalHarness.startPath
-            displayDonePath = externalHarness.donePath
+            if let helperBinaryPath = externalHarness.helperBinaryPath, !helperBinaryPath.isEmpty {
+                self.helperBinaryPath = helperBinaryPath
+                try launchDisplayHelper()
+                return
+            }
+            guard let readyPath = externalHarness.readyPath, !readyPath.isEmpty,
+                  let displayIDPath = externalHarness.displayIDPath, !displayIDPath.isEmpty,
+                  let startPath = externalHarness.startPath, !startPath.isEmpty,
+                  let donePath = externalHarness.donePath, !donePath.isEmpty else {
+                throw NSError(domain: "DisplayResolutionRegressionUITests", code: 3, userInfo: [
+                    NSLocalizedDescriptionKey: "Incomplete external display harness configuration"
+                ])
+            }
+            displayReadyPath = readyPath
+            self.displayIDPath = displayIDPath
+            displayStartPath = startPath
+            displayDonePath = donePath
             if let logPath = externalHarness.logPath, !logPath.isEmpty {
                 helperLogPath = logPath
             }
@@ -162,7 +175,8 @@ final class DisplayResolutionRegressionUITests: XCTestCase {
             displayIDPath: displayIDPath,
             startPath: startPath,
             donePath: donePath,
-            logPath: env["CMUX_UI_TEST_DISPLAY_LOG_PATH"]
+            logPath: env["CMUX_UI_TEST_DISPLAY_LOG_PATH"],
+            helperBinaryPath: nil
         )
     }
 
@@ -394,10 +408,11 @@ final class DisplayResolutionRegressionUITests: XCTestCase {
     }
 
     private struct ExternalDisplayHarness: Decodable {
-        let readyPath: String
-        let displayIDPath: String
-        let startPath: String
-        let donePath: String
+        let readyPath: String?
+        let displayIDPath: String?
+        let startPath: String?
+        let donePath: String?
         let logPath: String?
+        let helperBinaryPath: String?
     }
 }

From e99bc40285ea7995368b645eb516b6fa3afac54a Mon Sep 17 00:00:00 2001
From: Lawrence Chen <lawrencecchen@users.noreply.github.com>
Date: Wed, 18 Mar 2026 03:49:24 -0700
Subject: [PATCH 6/6] Fix test target build after split test sync

---
 .../AppDelegateShortcutRoutingTests.swift     | 10 ++---
 cmuxTests/BrowserConfigTests.swift            | 37 -------------------
 cmuxTests/BrowserPanelTests.swift             |  8 ++--
 cmuxTests/WindowAndDragTests.swift            | 37 +++++++++++++++++++
 cmuxTests/WorkspaceManualUnreadTests.swift    |  3 +-
 cmuxTests/WorkspaceUnitTests.swift            |  1 -
 6 files changed, 48 insertions(+), 48 deletions(-)

diff --git a/cmuxTests/AppDelegateShortcutRoutingTests.swift b/cmuxTests/AppDelegateShortcutRoutingTests.swift
index 8bc58a59..efb38674 100644
--- a/cmuxTests/AppDelegateShortcutRoutingTests.swift
+++ b/cmuxTests/AppDelegateShortcutRoutingTests.swift
@@ -6,7 +6,7 @@ import XCTest
 @testable import cmux
 #endif
 
-private let lastSurfaceCloseShortcutDefaultsKey = "closeWorkspaceOnLastSurfaceShortcut"
+private let appDelegateLastSurfaceCloseShortcutDefaultsKey = "closeWorkspaceOnLastSurfaceShortcut"
 
 @MainActor
 final class AppDelegateShortcutRoutingTests: XCTestCase {
@@ -725,13 +725,13 @@ final class AppDelegateShortcutRoutingTests: XCTestCase {
         }
 
         let defaults = UserDefaults.standard
-        let originalSetting = defaults.object(forKey: lastSurfaceCloseShortcutDefaultsKey)
-        defaults.set(false, forKey: lastSurfaceCloseShortcutDefaultsKey)
+        let originalSetting = defaults.object(forKey: appDelegateLastSurfaceCloseShortcutDefaultsKey)
+        defaults.set(false, forKey: appDelegateLastSurfaceCloseShortcutDefaultsKey)
         defer {
             if let originalSetting {
-                defaults.set(originalSetting, forKey: lastSurfaceCloseShortcutDefaultsKey)
+                defaults.set(originalSetting, forKey: appDelegateLastSurfaceCloseShortcutDefaultsKey)
             } else {
-                defaults.removeObject(forKey: lastSurfaceCloseShortcutDefaultsKey)
+                defaults.removeObject(forKey: appDelegateLastSurfaceCloseShortcutDefaultsKey)
             }
         }
 
diff --git a/cmuxTests/BrowserConfigTests.swift b/cmuxTests/BrowserConfigTests.swift
index 487c680c..b60ccef8 100644
--- a/cmuxTests/BrowserConfigTests.swift
+++ b/cmuxTests/BrowserConfigTests.swift
@@ -2737,43 +2737,6 @@ final class CmuxWebViewDragRoutingTests: XCTestCase {
     }
 }
 
-#if compiler(>=6.2)
-@available(macOS 26.0, *)
-private struct DragConfigurationOperationsSnapshot: Equatable {
-    let allowCopy: Bool
-    let allowMove: Bool
-    let allowDelete: Bool
-    let allowAlias: Bool
-}
-
-@available(macOS 26.0, *)
-private enum DragConfigurationSnapshotError: Error {
-    case missingBoolField(primary: String, fallback: String?)
-}
-
-@available(macOS 26.0, *)
-private func dragConfigurationOperationsSnapshot<T>(from operations: T) throws -> DragConfigurationOperationsSnapshot {
-    let mirror = Mirror(reflecting: operations)
-
-    func readBool(_ primary: String, fallback: String? = nil) throws -> Bool {
-        if let value = mirror.descendant(primary) as? Bool {
-            return value
-        }
-        if let fallback, let value = mirror.descendant(fallback) as? Bool {
-            return value
-        }
-        throw DragConfigurationSnapshotError.missingBoolField(primary: primary, fallback: fallback)
-    }
-
-    return try DragConfigurationOperationsSnapshot(
-        allowCopy: readBool("allowCopy", fallback: "_allowCopy"),
-        allowMove: readBool("allowMove", fallback: "_allowMove"),
-        allowDelete: readBool("allowDelete", fallback: "_allowDelete"),
-        allowAlias: readBool("allowAlias", fallback: "_allowAlias")
-    )
-}
-
-
 final class BrowserLinkOpenSettingsTests: XCTestCase {
     private var suiteName: String!
     private var defaults: UserDefaults!
diff --git a/cmuxTests/BrowserPanelTests.swift b/cmuxTests/BrowserPanelTests.swift
index 104cecbf..5c61be3d 100644
--- a/cmuxTests/BrowserPanelTests.swift
+++ b/cmuxTests/BrowserPanelTests.swift
@@ -13,7 +13,7 @@ import UserNotifications
 @testable import cmux
 #endif
 
-func drainMainQueue() {
+private func drainBrowserPanelMainQueue() {
     let expectation = XCTestExpectation(description: "drain main queue")
     DispatchQueue.main.async {
         expectation.fulfill()
@@ -22,7 +22,7 @@ func drainMainQueue() {
 }
 
 @MainActor
-func makeTemporaryBrowserProfile(named prefix: String) throws -> BrowserProfileDefinition {
+private func makeTemporaryBrowserPanelProfile(named prefix: String) throws -> BrowserProfileDefinition {
     try XCTUnwrap(
         BrowserProfileStore.shared.createProfile(
             named: "\(prefix)-\(UUID().uuidString)"
@@ -107,7 +107,7 @@ final class BrowserPanelOmnibarPillBackgroundColorTests: XCTestCase {
 @MainActor
 final class BrowserPanelProfileIsolationTests: XCTestCase {
     func testStaleDidFinishDoesNotRecordVisitIntoSwitchedProfileHistory() throws {
-        let alternateProfile = try makeTemporaryBrowserProfile(named: "Switched")
+        let alternateProfile = try makeTemporaryBrowserPanelProfile(named: "Switched")
         let defaultStore = BrowserHistoryStore.shared
         let alternateStore = BrowserProfileStore.shared.historyStore(for: alternateProfile.id)
         defaultStore.clearHistory()
@@ -137,7 +137,7 @@ final class BrowserPanelProfileIsolationTests: XCTestCase {
         alternateStore.clearHistory()
 
         staleDelegate.webView?(staleWebView, didFinish: nil)
-        drainMainQueue()
+        drainBrowserPanelMainQueue()
 
         XCTAssertTrue(
             defaultStore.entries.isEmpty,
diff --git a/cmuxTests/WindowAndDragTests.swift b/cmuxTests/WindowAndDragTests.swift
index e618949f..6964c45f 100644
--- a/cmuxTests/WindowAndDragTests.swift
+++ b/cmuxTests/WindowAndDragTests.swift
@@ -299,6 +299,42 @@ final class FocusFlashPatternTests: XCTestCase {
 }
 
 
+@available(macOS 26.0, *)
+private struct DragConfigurationOperationsSnapshot: Equatable {
+    let allowCopy: Bool
+    let allowMove: Bool
+    let allowDelete: Bool
+    let allowAlias: Bool
+}
+
+@available(macOS 26.0, *)
+private enum DragConfigurationSnapshotError: Error {
+    case missingBoolField(primary: String, fallback: String?)
+}
+
+@available(macOS 26.0, *)
+private func dragConfigurationOperationsSnapshot<T>(from operations: T) throws -> DragConfigurationOperationsSnapshot {
+    let mirror = Mirror(reflecting: operations)
+
+    func readBool(_ primary: String, fallback: String? = nil) throws -> Bool {
+        if let value = mirror.descendant(primary) as? Bool {
+            return value
+        }
+        if let fallback, let value = mirror.descendant(fallback) as? Bool {
+            return value
+        }
+        throw DragConfigurationSnapshotError.missingBoolField(primary: primary, fallback: fallback)
+    }
+
+    return try DragConfigurationOperationsSnapshot(
+        allowCopy: readBool("allowCopy", fallback: "_allowCopy"),
+        allowMove: readBool("allowMove", fallback: "_allowMove"),
+        allowDelete: readBool("allowDelete", fallback: "_allowDelete"),
+        allowAlias: readBool("allowAlias", fallback: "_allowAlias")
+    )
+}
+
+#if compiler(>=6.2)
 @MainActor
 final class InternalTabDragConfigurationTests: XCTestCase {
     func testDisablesExternalOperationsForInternalTabDrags() throws {
@@ -1080,3 +1116,4 @@ final class MarkdownPanelPointerObserverViewTests: XCTestCase {
         XCTAssertNil(overlay.hitTest(NSPoint(x: 40, y: 30)))
     }
 }
+#endif
diff --git a/cmuxTests/WorkspaceManualUnreadTests.swift b/cmuxTests/WorkspaceManualUnreadTests.swift
index 1610dc34..6fbe30c3 100644
--- a/cmuxTests/WorkspaceManualUnreadTests.swift
+++ b/cmuxTests/WorkspaceManualUnreadTests.swift
@@ -7,6 +7,7 @@ import AppKit
 @testable import cmux
 #endif
 
+@MainActor
 final class WorkspaceManualUnreadTests: XCTestCase {
     func testShouldClearManualUnreadWhenFocusMovesToDifferentPanel() {
         let previousFocusedPanelId = UUID()
@@ -281,7 +282,7 @@ final class CommandPaletteSwitcherSearchIndexerTests: XCTestCase {
         XCTAssertFalse(keywords.contains("cmd-palette-indexing"))
     }
 
-    func testSurfaceDetailOutranksWorkspaceDetailForPathToken() {
+    func testSurfaceDetailOutranksWorkspaceDetailForPathToken() throws {
         let metadata = CommandPaletteSwitcherSearchMetadata(
             directories: ["/tmp/worktrees/cmux"],
             branches: ["feature/cmd-palette"],
diff --git a/cmuxTests/WorkspaceUnitTests.swift b/cmuxTests/WorkspaceUnitTests.swift
index 5bd83682..719baa43 100644
--- a/cmuxTests/WorkspaceUnitTests.swift
+++ b/cmuxTests/WorkspaceUnitTests.swift
@@ -1896,4 +1896,3 @@ final class SidebarWorkspaceShortcutHintMetricsTests: XCTestCase {
         XCTAssertGreaterThan(widened, base)
     }
 }
-#endif