Bug 1556131 - P3. Enable check on automation. r=njn

Differential Revision: https://phabricator.services.mozilla.com/D34475

--HG--
extra : moz-landing-system : lando

browser/components/preferences/in-content/tests/browser_layersacceleration.js

@@ -1,5 +1,11 @@
 add_task(async function() {
-  SpecialPowers.pushPrefEnv({set: [
+  // We must temporarily disable `Once` StaticPrefs check for the duration of
+  // this test (see bug 1556131). We must do so in a separate operation as
+  // pushPrefEnv doesn't set the preferences in the order one could expect.
+  await SpecialPowers.pushPrefEnv({set: [
+    ["preferences.force-disable.check.once.policy", true],
+  ]});
+  await SpecialPowers.pushPrefEnv({set: [
     ["gfx.direct2d.disabled", false],
     ["layers.acceleration.disabled", false],
   ]});

browser/components/preferences/in-content/tests/browser_performance.js

@@ -2,6 +2,12 @@ const DEFAULT_HW_ACCEL_PREF = Services.prefs.getDefaultBranch(null).getBoolPref(
 const DEFAULT_PROCESS_COUNT = Services.prefs.getDefaultBranch(null).getIntPref("dom.ipc.processCount");
 
 add_task(async function() {
+  // We must temporarily disable `Once` StaticPrefs check for the duration of
+  // this test (see bug 1556131). We must do so in a separate operation as
+  // pushPrefEnv doesn't set the preferences in the order one could expect.
+  await SpecialPowers.pushPrefEnv({set: [
+    ["preferences.force-disable.check.once.policy", true],
+  ]});
   await SpecialPowers.pushPrefEnv({set: [
     ["layers.acceleration.disabled", DEFAULT_HW_ACCEL_PREF],
     ["dom.ipc.processCount", DEFAULT_PROCESS_COUNT],

browser/components/preferences/in-content/tests/browser_performance_e10srollout.js

@@ -2,6 +2,12 @@ const DEFAULT_HW_ACCEL_PREF = Services.prefs.getDefaultBranch(null).getBoolPref(
 const DEFAULT_PROCESS_COUNT = Services.prefs.getDefaultBranch(null).getIntPref("dom.ipc.processCount");
 
 add_task(async function() {
+  // We must temporarily disable `Once` StaticPrefs check for the duration of
+  // this test (see bug 1556131). We must do so in a separate operation as
+  // pushPrefEnv doesn't set the preferences in the order one could expect.
+  await SpecialPowers.pushPrefEnv({set: [
+    ["preferences.force-disable.check.once.policy", true],
+  ]});
   await SpecialPowers.pushPrefEnv({set: [
     ["layers.acceleration.disabled", DEFAULT_HW_ACCEL_PREF],
     ["dom.ipc.processCount", DEFAULT_PROCESS_COUNT],

browser/components/preferences/in-content/tests/browser_performance_non_e10s.js

@@ -2,6 +2,12 @@ const DEFAULT_HW_ACCEL_PREF = Services.prefs.getDefaultBranch(null).getBoolPref(
 const DEFAULT_PROCESS_COUNT = Services.prefs.getDefaultBranch(null).getIntPref("dom.ipc.processCount");
 
 add_task(async function() {
+  // We must temporarily disable `Once` StaticPrefs check for the duration of
+  // this test (see bug 1556131). We must do so in a separate operation as
+  // pushPrefEnv doesn't set the preferences in the order one could expect.
+  await SpecialPowers.pushPrefEnv({set: [
+    ["preferences.force-disable.check.once.policy", true],
+  ]});
   await SpecialPowers.pushPrefEnv({set: [
     ["layers.acceleration.disabled", DEFAULT_HW_ACCEL_PREF],
     ["dom.ipc.processCount", DEFAULT_PROCESS_COUNT],

modules/libpref/Preferences.cpp

@@ -87,6 +87,7 @@
 #include "PLDHashTable.h"
 #include "plstr.h"
 #include "prlink.h"
+#include "xpcpublic.h"
 
 #ifdef DEBUG
 #  include <map>
@@ -1705,7 +1706,9 @@ static void NotifyCallbacks(const char* aPrefName, const PrefWrapper* aPref) {
   }
 
 #ifdef DEBUG
-  if (XRE_IsParentProcess() && StaticPrefs::preferences_check_once_policy()) {
+  if (XRE_IsParentProcess() &&
+      !StaticPrefs::preferences_force_disable_check_once_policy() &&
+      (StaticPrefs::preferences_check_once_policy() || xpc::IsInAutomation())) {
     // Check that we aren't modifying a `Once` pref using that prefName.
     // We have about 100 `Once` StaticPrefs defined. std::map performs a search
     // in O(log n), so this is fast enough for our case.
@@ -5517,26 +5520,27 @@ void StaticPrefs::InitOncePrefs() {
   // and that maybe instead they should have been made `Live`.
 #define PREF(name, cpp_type, value)
 #ifdef DEBUG
-#  define VARCACHE_PREF(policy, name, id, cpp_type, value)                     \
-    if (UpdatePolicy::policy == UpdatePolicy::Once) {                          \
-      StaticPrefs::sVarCache_##id = PreferencesInternalMethods::GetPref(       \
-          name, StripAtomic<cpp_type>(value));                                 \
-      auto checkPref = [&]() {                                                 \
-        if (!sOncePrefRead) {                                                  \
-          return;                                                              \
-        }                                                                      \
-        StripAtomic<cpp_type> staticPrefValue = StaticPrefs::id();             \
-        StripAtomic<cpp_type> preferenceValue =                                \
-            PreferencesInternalMethods::GetPref(Get##id##PrefName(),           \
-                                                StripAtomic<cpp_type>(value)); \
-        MOZ_ASSERT(                                                            \
-            staticPrefValue == preferenceValue,                                \
-            "Preference '" name "' got modified since StaticPrefs::" #id       \
-            " got initialized. Consider using a `Live` StaticPrefs instead");  \
-      };                                                                       \
-      gOnceStaticPrefsAntiFootgun->insert(                                     \
-          std::pair<const char*, AntiFootgunCallback>(Get##id##PrefName(),     \
-                                                      std::move(checkPref)));  \
+#  define VARCACHE_PREF(policy, name, id, cpp_type, value)                    \
+    if (UpdatePolicy::policy == UpdatePolicy::Once) {                         \
+      StaticPrefs::sVarCache_##id = PreferencesInternalMethods::GetPref(      \
+          name, StripAtomic<cpp_type>(value));                                \
+      auto checkPref = [&]() {                                                \
+        if (!sOncePrefRead) {                                                 \
+          return;                                                             \
+        }                                                                     \
+        StripAtomic<cpp_type> staticPrefValue = StaticPrefs::id();            \
+        StripAtomic<cpp_type> preferenceValue =                               \
+            PreferencesInternalMethods::GetPref(                              \
+                StaticPrefs::Get##id##PrefName(),                             \
+                StripAtomic<cpp_type>(value));                                \
+        MOZ_ASSERT(                                                           \
+            staticPrefValue == preferenceValue,                               \
+            "Preference '" name "' got modified since StaticPrefs::" #id      \
+            " got initialized. Consider using a `Live` StaticPrefs instead"); \
+      };                                                                      \
+      gOnceStaticPrefsAntiFootgun->insert(                                    \
+          std::pair<const char*, AntiFootgunCallback>(Get##id##PrefName(),    \
+                                                      std::move(checkPref))); \
     }
 #else
 #  define VARCACHE_PREF(policy, name, id, cpp_type, value)               \

modules/libpref/init/StaticPrefList.h

@@ -6795,6 +6795,16 @@ VARCACHE_PREF(
   preferences_check_once_policy,
   bool, false
 )
+
+// If set to true, StaticPrefs Once policy check will be skipped during
+// automation regression test. Use with care. This pref must be set back to
+// false as soon as specific test has completed.
+VARCACHE_PREF(
+  Live,
+  "preferences.force-disable.check.once.policy",
+  preferences_force_disable_check_once_policy,
+  bool, false
+)
 #endif
 
 //---------------------------------------------------------------------------