From c2cd79b547a5737cb98587225e62ce01094c5ef6 Mon Sep 17 00:00:00 2001
From: Gabriel Brown <gbrown@ksensetech.com>
Date: Tue, 18 Aug 2026 02:53:01 -0400
Subject: [PATCH] Serialize display recovery checks

---
 config/dot/quickshell/services/Displays.qml | 25 ++++++++++++++-------
 tests/quickshell/displays-contract.sh       | 18 ++++++++++++++-
 2 files changed, 34 insertions(+), 9 deletions(-)

diff --git a/config/dot/quickshell/services/Displays.qml b/config/dot/quickshell/services/Displays.qml
index 20fd834..19c40b8 100644
--- a/config/dot/quickshell/services/Displays.qml
+++ b/config/dot/quickshell/services/Displays.qml
@@ -85,7 +85,8 @@ Singleton {
             if (!root.awaitingConfirmation)
                 return;
             if (root.revertQueued) {
-                root.performRevert();
+                if (!query.running)
+                    root.performRevert();
                 return;
             }
             if (exitCode !== 0) {
@@ -93,6 +94,7 @@ Singleton {
                 return;
             }
             verifyTimer.attempts = 0;
+            verifyTimer.ticks = 0;
             verifyTimer.restart();
         }
     }
@@ -104,17 +106,20 @@ Singleton {
             // success without applying a value, so exact readback decides.
             root.revertVerificationActive = true;
             revertVerifyTimer.attempts = 0;
+            revertVerifyTimer.ticks = 0;
             revertVerifyTimer.restart();
         }
     }
 
     Component.onCompleted: root.refresh()
 
-    function refresh(): void {
+    function refresh(): bool {
         if (!query.running) {
             query.generation = root.operationGeneration;
             query.running = true;
+            return true;
         }
+        return false;
     }
 
     function parse(text: string, generation: int): void {
@@ -411,26 +416,29 @@ Singleton {
     Timer {
         id: verifyTimer
         property int attempts: 0
+        property int ticks: 0
         interval: 120
         repeat: true
         onTriggered: {
-            attempts++;
-            if (attempts > 25) {
+            ticks++;
+            if (ticks > 50) {
                 root.revertWithMessage("The display did not apply that setting, so Panama restored the previous one.");
                 return;
             }
-            root.refresh();
+            if (root.refresh())
+                attempts++;
         }
     }
 
     Timer {
         id: revertVerifyTimer
         property int attempts: 0
+        property int ticks: 0
         interval: 120
         repeat: true
         onTriggered: {
-            attempts++;
-            if (attempts > 25) {
+            ticks++;
+            if (ticks > 50) {
                 stop();
                 root.revertVerificationActive = false;
                 root.revertGeneration = -1;
@@ -439,7 +447,8 @@ Singleton {
                 root.lastError = "The previous display setting could not be verified. Open Displays and restore it manually.";
                 return;
             }
-            root.refresh();
+            if (root.refresh())
+                attempts++;
         }
     }
 
diff --git a/tests/quickshell/displays-contract.sh b/tests/quickshell/displays-contract.sh
index ec0acd0..a7fda87 100755
--- a/tests/quickshell/displays-contract.sh
+++ b/tests/quickshell/displays-contract.sh
@@ -225,8 +225,24 @@ KINDS
 now="$(status)"
 [[ "$(jq -r .scale <<<"$now")" == "$original_scale" ]] || fail 'a refused change still altered the scale'
 
-# ── An unconfirmed change reverts on its own and stores nothing ──────────────
+# An immediate Revert may race both the apply process and its first readback.
+# It must queue until both are clear, then verify the original generation.
 target_scale=$(awk -v s="$original_scale" 'BEGIN { print (s == 1.25) ? 1.5 : 1.25 }')
+[[ "$(run ipc call displays-test applyScale "$target_scale")" == "true" ]] \
+    || fail 'the immediate-revert fixture could not apply'
+run ipc call displays-test revertChange >/dev/null
+immediate_reverted=false
+for _ in $(seq 1 60); do
+    if display_is_restored && [[ "$(status | jq -r .awaiting)" == "false" ]]; then
+        immediate_reverted=true
+        break
+    fi
+    sleep 0.2
+done
+[[ "$immediate_reverted" == true ]] \
+    || fail 'an immediate Revert raced the apply/readback and did not restore the display'
+
+# ── An unconfirmed change reverts on its own and stores nothing ──────────────
 [[ "$(run ipc call displays-test applyScale "$target_scale")" == "true" ]] \
     || fail 'a valid scale change was refused'