[gen_l10n] Fix plural parsing for translated messages (#53954)

dev/tools/localization/gen_l10n.dart

@@ -85,7 +85,7 @@ String generateNumberFormattingLogic(Message message) {
   return formatStatements.isEmpty ? '@(none)' : formatStatements.join('');
 }
 
-String generatePluralMethod(Message message) {
+String generatePluralMethod(Message message, AppResourceBundle bundle) {
   if (message.placeholders.isEmpty) {
     throw L10nException(
       'Unable to find placeholders for the plural message: ${message.resourceId}.\n'
@@ -96,7 +96,7 @@ String generatePluralMethod(Message message) {
 
   // To make it easier to parse the plurals message, temporarily replace each
   // "{placeholder}" parameter with "#placeholder#".
-  String easyMessage = message.value;
+  String easyMessage = bundle.translationFor(message);
   for (final Placeholder placeholder in message.placeholders)
     easyMessage = easyMessage.replaceAll('{${placeholder.name}}', '#${placeholder.name}#');
 
@@ -168,7 +168,7 @@ String generateMethod(Message message, AppResourceBundle bundle) {
   }
 
   if (message.isPlural) {
-    return generatePluralMethod(message);
+    return generatePluralMethod(message, bundle);
   }
 
   if (message.placeholdersRequireFormatting) {

packages/flutter_tools/test/integration.shard/gen_l10n_test.dart

@@ -92,37 +92,40 @@ void main() {
       '#l10n 13 (Hello GB fallback World)\n'
       '#l10n 14 (--- zh ---)\n'
       '#l10n 15 (你好世界)\n'
-      '#l10n 16 (--- scriptCode: zh_Hans ---)\n'
-      '#l10n 17 (简体你好世界)\n'
-      '#l10n 18 (--- scriptCode - zh_Hant ---)\n'
-      '#l10n 19 (繁體你好世界)\n'
-      '#l10n 20 (--- scriptCode - zh_Hant_TW ---)\n'
-      '#l10n 21 (台灣繁體你好世界)\n'
-      '#l10n 22 (--- General formatting tests ---)\n'
-      '#l10n 23 (Hello World)\n'
-      '#l10n 24 (Hello _NEWLINE_ World)\n'
-      '#l10n 25 (Hello World)\n'
+      '#l10n 16 (你好)\n'
+      '#l10n 17 (你好世界)\n'
+      '#l10n 18 (你好2个其他世界)\n'
+      '#l10n 19 (--- scriptCode: zh_Hans ---)\n'
+      '#l10n 20 (简体你好世界)\n'
+      '#l10n 21 (--- scriptCode - zh_Hant ---)\n'
+      '#l10n 22 (繁體你好世界)\n'
+      '#l10n 23 (--- scriptCode - zh_Hant_TW ---)\n'
+      '#l10n 24 (台灣繁體你好世界)\n'
+      '#l10n 25 (--- General formatting tests ---)\n'
       '#l10n 26 (Hello World)\n'
-      '#l10n 27 (Hello World on Friday, January 1, 1960)\n'
-      '#l10n 28 (Hello world argument on 1/1/1960 at 00:00)\n'
-      '#l10n 29 (Hello World from 1960 to 2020)\n'
-      '#l10n 30 (Hello for 123)\n'
-      '#l10n 31 (Hello for price USD123.00)\n'
-      '#l10n 32 (Hello)\n'
-      '#l10n 33 (Hello World)\n'
-      '#l10n 34 (Hello two worlds)\n'
+      '#l10n 27 (Hello _NEWLINE_ World)\n'
+      '#l10n 28 (Hello World)\n'
+      '#l10n 29 (Hello World)\n'
+      '#l10n 30 (Hello World on Friday, January 1, 1960)\n'
+      '#l10n 31 (Hello world argument on 1/1/1960 at 00:00)\n'
+      '#l10n 32 (Hello World from 1960 to 2020)\n'
+      '#l10n 33 (Hello for 123)\n'
+      '#l10n 34 (Hello for price USD123.00)\n'
       '#l10n 35 (Hello)\n'
-      '#l10n 36 (Hello new World)\n'
-      '#l10n 37 (Hello two new worlds)\n'
-      '#l10n 38 (Hello on Friday, January 1, 1960)\n'
-      '#l10n 39 (Hello World, on Friday, January 1, 1960)\n'
-      '#l10n 40 (Hello two worlds, on Friday, January 1, 1960)\n'
-      '#l10n 41 (Hello other 0 worlds, with a total of 100 citizens)\n'
-      '#l10n 42 (Hello World of 101 citizens)\n'
-      '#l10n 43 (Hello two worlds with 102 total citizens)\n'
-      '#l10n 44 ([Hello] -World- #123#)\n'
-      '#l10n 45 (Flutter\'s amazing!)\n'
-      '#l10n 46 (Flutter is "amazing"!)\n'
+      '#l10n 36 (Hello World)\n'
+      '#l10n 37 (Hello two worlds)\n'
+      '#l10n 38 (Hello)\n'
+      '#l10n 39 (Hello new World)\n'
+      '#l10n 40 (Hello two new worlds)\n'
+      '#l10n 41 (Hello on Friday, January 1, 1960)\n'
+      '#l10n 42 (Hello World, on Friday, January 1, 1960)\n'
+      '#l10n 43 (Hello two worlds, on Friday, January 1, 1960)\n'
+      '#l10n 44 (Hello other 0 worlds, with a total of 100 citizens)\n'
+      '#l10n 45 (Hello World of 101 citizens)\n'
+      '#l10n 46 (Hello two worlds with 102 total citizens)\n'
+      '#l10n 47 ([Hello] -World- #123#)\n'
+      '#l10n 48 (Flutter\'s amazing!)\n'
+      '#l10n 49 (Flutter is "amazing"!)\n'
       '#l10n END\n'
     );
   });

packages/flutter_tools/test/integration.shard/test_data/gen_l10n_project.dart

@@ -126,6 +126,9 @@ class Home extends StatelessWidget {
           callback: (BuildContext context) {
             results.add('--- zh ---');
             results.add(AppLocalizations.of(context).helloWorld);
+            results.add(AppLocalizations.of(context).helloWorlds(0));
+            results.add(AppLocalizations.of(context).helloWorlds(1));
+            results.add(AppLocalizations.of(context).helloWorlds(2));
           },
         ),
         LocaleBuilder(
@@ -402,13 +405,14 @@ void main() {
 }
 ''';
 
-  // Only tests `helloWorld`. The rest of the messages are added out of
-  // necessity since every base class requires an override for every
-  // message.
+  // Only tests `helloWorld` and `helloWorlds`. The rest of the messages
+  // are added out of necessity since every base class requires an
+  // override for every message.
   final String appZh = r'''
 {
   "@@locale": "zh",
   "helloWorld": "你好世界",
+  "helloWorlds": "{count,plural, =0{你好} =1{你好世界} other{你好{count}个其他世界}}",
   "helloNewlineWorld": "Hello \n World",
   "hello": "Hello {world}",
   "greeting": "{hello} {world}",
@@ -417,7 +421,6 @@ void main() {
   "helloOn": "Hello {world} on {date} at {time}",
   "helloFor": "Hello for {value}",
   "helloCost": "Hello for {price} {value}",
-  "helloWorlds": "{count,plural, =0{Hello} =1{Hello World} =2{Hello two worlds} few{Hello {count} worlds} many{Hello all {count} worlds} other{Hello other {count} worlds}}",
   "helloAdjectiveWorlds": "{count,plural, =0{Hello} =1{Hello {adjective} World} =2{Hello two {adjective} worlds} other{Hello other {count} {adjective} worlds}}",
   "helloWorldsOn": "{count,plural, =0{Hello on {date}} =1{Hello World, on {date}} =2{Hello two worlds, on {date}} other{Hello other {count} worlds, on {date}}}",
   "helloWorldPopulation": "{count,plural, =1{Hello World of {population} citizens} =2{Hello two worlds with {population} total citizens} many{Hello all {count} worlds, with a total of {population} citizens} other{Hello other {count} worlds, with a total of {population} citizens}}",