Make the 'time to update' message depend up on the channel. (#24173)

Fixes #24158

packages/flutter_tools/lib/src/version.dart

@@ -207,20 +207,34 @@ class FlutterVersion {
   /// The amount of time we wait before pinging the server to check for the
   /// availability of a newer version of Flutter.
   @visibleForTesting
-  static const Duration kCheckAgeConsideredUpToDate = Duration(days: 3);
+  static const Duration checkAgeConsideredUpToDate = Duration(days: 3);
 
   /// We warn the user if the age of their Flutter installation is greater than
-  /// this duration.
+  /// this duration. The durations are slightly longer than the expected release
+  /// cadence for each channel, to give the user a grace period before they get
+  /// notified.
   ///
-  /// This is set to 5 weeks because releases are currently around every 4 weeks.
+  /// For example, for the beta channel, this is set to five weeks because
+  /// beta releases happen approximately every month.
   @visibleForTesting
-  static const Duration kVersionAgeConsideredUpToDate = Duration(days: 35);
+  static Duration versionAgeConsideredUpToDate(String channel) {
+    switch (channel) {
+      case 'stable':
+        return const Duration(days: 365 ~/ 2); // Six months
+      case 'beta':
+        return const Duration(days: 7 * 8); // Eight weeks
+      case 'dev':
+        return const Duration(days: 7 * 4); // Four weeks
+      default:
+        return const Duration(days: 7 * 3); // Three weeks
+    }
+  }
 
   /// The amount of time we wait between issuing a warning.
   ///
   /// This is to avoid annoying users who are unable to upgrade right away.
   @visibleForTesting
-  static const Duration kMaxTimeSinceLastWarning = Duration(days: 1);
+  static const Duration maxTimeSinceLastWarning = Duration(days: 1);
 
   /// The amount of time we pause for to let the user read the message about
   /// outdated Flutter installation.
@@ -238,7 +252,7 @@ class FlutterVersion {
   static Future<void> resetFlutterVersionFreshnessCheck() async {
     try {
       await Cache.instance.getStampFileFor(
-        VersionCheckStamp.kFlutterVersionCheckStampFile,
+        VersionCheckStamp.flutterVersionCheckStampFile,
       ).delete();
     } on FileSystemException {
       // Ignore, since we don't mind if the file didn't exist in the first place.
@@ -258,7 +272,7 @@ class FlutterVersion {
 
     final DateTime localFrameworkCommitDate = DateTime.parse(frameworkCommitDate);
     final Duration frameworkAge = _clock.now().difference(localFrameworkCommitDate);
-    final bool installationSeemsOutdated = frameworkAge > kVersionAgeConsideredUpToDate;
+    final bool installationSeemsOutdated = frameworkAge > versionAgeConsideredUpToDate(channel);
 
     // Get whether there's a newer version on the remote. This only goes
     // to the server if we haven't checked recently so won't happen on every
@@ -273,8 +287,8 @@ class FlutterVersion {
 
     // Do not load the stamp before the above server check as it may modify the stamp file.
     final VersionCheckStamp stamp = await VersionCheckStamp.load();
-    final DateTime lastTimeWarningWasPrinted = stamp.lastTimeWarningWasPrinted ?? _clock.ago(kMaxTimeSinceLastWarning * 2);
-    final bool beenAWhileSinceWarningWasPrinted = _clock.now().difference(lastTimeWarningWasPrinted) > kMaxTimeSinceLastWarning;
+    final DateTime lastTimeWarningWasPrinted = stamp.lastTimeWarningWasPrinted ?? _clock.ago(maxTimeSinceLastWarning * 2);
+    final bool beenAWhileSinceWarningWasPrinted = _clock.now().difference(lastTimeWarningWasPrinted) > maxTimeSinceLastWarning;
 
     // We show a warning if either we know there is a new remote version, or we couldn't tell but the local
     // version is outdated.
@@ -327,7 +341,7 @@ class FlutterVersion {
   /// Gets the release date of the latest available Flutter version.
   ///
   /// This method sends a server request if it's been more than
-  /// [kCheckAgeConsideredUpToDate] since the last version check.
+  /// [checkAgeConsideredUpToDate] since the last version check.
   ///
   /// Returns null if the cached version is out-of-date or missing, and we are
   /// unable to reach the server to get the latest version.
@@ -339,7 +353,7 @@ class FlutterVersion {
       final Duration timeSinceLastCheck = _clock.now().difference(versionCheckStamp.lastTimeVersionWasChecked);
 
       // Don't ping the server too often. Return cached value if it's fresh.
-      if (timeSinceLastCheck < kCheckAgeConsideredUpToDate)
+      if (timeSinceLastCheck < checkAgeConsideredUpToDate)
         return versionCheckStamp.lastKnownRemoteVersion;
     }
 
@@ -381,10 +395,10 @@ class VersionCheckStamp {
 
   /// The prefix of the stamp file where we cache Flutter version check data.
   @visibleForTesting
-  static const String kFlutterVersionCheckStampFile = 'flutter_version_check';
+  static const String flutterVersionCheckStampFile = 'flutter_version_check';
 
   static Future<VersionCheckStamp> load() async {
-    final String versionCheckStamp = Cache.instance.getStampFor(kFlutterVersionCheckStampFile);
+    final String versionCheckStamp = Cache.instance.getStampFor(flutterVersionCheckStampFile);
 
     if (versionCheckStamp != null) {
       // Attempt to parse stamp JSON.
@@ -435,8 +449,8 @@ class VersionCheckStamp {
     if (newTimeWarningWasPrinted != null)
       jsonData['lastTimeWarningWasPrinted'] = '$newTimeWarningWasPrinted';
 
-    const JsonEncoder kPrettyJsonEncoder = JsonEncoder.withIndent('  ');
-    Cache.instance.setStampFor(kFlutterVersionCheckStampFile, kPrettyJsonEncoder.convert(jsonData));
+    const JsonEncoder prettyJsonEncoder = JsonEncoder.withIndent('  ');
+    Cache.instance.setStampFor(flutterVersionCheckStampFile, prettyJsonEncoder.convert(jsonData));
   }
 
   Map<String, String> toJson({

packages/flutter_tools/test/channel_test.dart

@@ -188,7 +188,7 @@ void main() {
       )).thenAnswer((_) => Future<Process>.value(createMockProcess()));
 
       final File versionCheckFile = Cache.instance.getStampFileFor(
-        VersionCheckStamp.kFlutterVersionCheckStampFile,
+        VersionCheckStamp.flutterVersionCheckStampFile,
       );
 
       /// Create a bogus "leftover" version check file to make sure it gets