[Spellcheck][Android] - Fix empty paragraph platform error, and concurrent spell check platform error (Resolves #2640) (#2641)

Author: matthew-carroll

super_editor_spellcheck/example/android/settings.gradle

@@ -18,7 +18,7 @@ pluginManagement {
 
 plugins {
     id "dev.flutter.flutter-plugin-loader" version "1.0.0"
-    id "com.android.application" version "8.1.0" apply false
+    id "com.android.application" version "8.2.1" apply false
     id "org.jetbrains.kotlin.android" version "1.8.22" apply false
 }
 

super_editor_spellcheck/example/pubspec.lock

@@ -37,10 +37,10 @@ packages:
     dependency: transitive
     description:
       name: attributed_text
-      sha256: d16c10850371421a778474ac24c24b4ab8708e3e53f3796f8d9ea2a41a25a59a
+      sha256: "9d8bdc6e54387f31e52d2dcc3d93d656072582a44bcaa855c9ea8b3b2fa7abd3"
       url: "https://pub.dev"
     source: hosted
-    version: "0.4.2"
+    version: "0.4.4"
   boolean_selector:
     dependency: transitive
     description:
@@ -147,6 +147,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "3.0.2"
+  flutter_plugin_android_lifecycle:
+    dependency: transitive
+    description:
+      name: flutter_plugin_android_lifecycle
+      sha256: "5a1e6fb2c0561958d7e4c33574674bda7b77caaca7a33b758876956f2902eea3"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.0.27"
   flutter_test:
     dependency: "direct dev"
     description: flutter
@@ -498,7 +506,7 @@ packages:
       path: "../../super_editor"
       relative: true
     source: path
-    version: "0.3.0-dev.15"
+    version: "0.3.0-dev.23"
   super_editor_spellcheck:
     dependency: "direct main"
     description:
@@ -510,10 +518,10 @@ packages:
     dependency: transitive
     description:
       name: super_keyboard
-      sha256: c8e303cd7bc1fc62732213f0f2660273a078be23eae7a4219d0ab3dd0b0ccb9a
+      sha256: "06662d12c88f0d0f0979d1a27729007a9b5e389e3b9a8adf2531e4c562df2540"
       url: "https://pub.dev"
     source: hosted
-    version: "0.1.0"
+    version: "0.1.1"
   super_text_layout:
     dependency: transitive
     description:
@@ -707,5 +715,5 @@ packages:
     source: hosted
     version: "3.1.2"
 sdks:
-  dart: ">=3.5.0 <4.0.0"
-  flutter: ">=3.19.0"
+  dart: ">=3.6.0 <4.0.0"
+  flutter: ">=3.27.0"

super_editor_spellcheck/lib/src/super_editor/spelling_and_grammar_plugin.dart

@@ -400,19 +400,36 @@ class SpellingAndGrammarReaction implements EditReaction {
     final textErrors = <TextError>{};
     final spellingSuggestions = <TextRange, SpellingError>{};
 
+    final plainText = _filterIgnoredRanges(textNode);
+    if (plainText.isEmpty) {
+      // On Android it appears that running spell check on an empty string breaks
+      // spell check for the remainder of the app session, so don't even try.
+      // https://github.com/superlistapp/super_editor/issues/2640
+      return;
+    }
+
     // Track this spelling and grammar request to make sure we don't process
     // the response out of order with other requests.
     _asyncRequestIds[textNode.id] ??= 0;
     final requestId = _asyncRequestIds[textNode.id]! + 1;
     _asyncRequestIds[textNode.id] = requestId;
 
-    final plainText = _filterIgnoredRanges(textNode);
-
     if (isSpellCheckEnabled) {
-      final suggestions = await _spellCheckService.fetchSpellCheckSuggestions(
-        PlatformDispatcher.instance.locale,
-        plainText,
-      );
+      // Android can't execute concurrent spell checks and returns `null` when we try to run a 2nd+ spell check
+      // at the same time. We'll retry our spell check up to this number of times before giving up.
+      // https://github.com/superlistapp/super_editor/issues/2640
+      const maxTryCount = 5;
+
+      List<SuggestionSpan>? suggestions;
+      int tryCount = 0;
+      do {
+        suggestions = await _spellCheckService.fetchSpellCheckSuggestions(
+          PlatformDispatcher.instance.locale,
+          plainText,
+        );
+        tryCount += 1;
+      } while (suggestions == null && tryCount < maxTryCount);
+
       if (suggestions != null) {
         for (final suggestion in suggestions) {
           final misspelledWord = plainText.substring(suggestion.range.start, suggestion.range.end);