Improved error handling

Author: tmaxxdd

CHANGELOG.md

@@ -1,3 +1,7 @@
 ## 0.0.1
 
-* TODO: Describe initial release.
+### Added
+
+- `getLanguages` method
+- `getThemes` method
+- `getHighlights` method

example/lib/main.dart

@@ -13,7 +13,7 @@ class MyApp extends StatefulWidget {
 }
 
 class _MyAppState extends State<MyApp> {
-  final _highlightsPlugin = HighlightsPlugin();
+  final _highlightsPlugin = HighlightsPlugin(debug: true);
 
   String? _code;
   String? _language;

lib/highlights_plugin.dart

@@ -1,32 +1,63 @@
+import 'package:flutter/cupertino.dart';
 import 'package:highlights_plugin/model/code_highlight.dart';
 import 'package:highlights_plugin/model/phrase_location.dart';
-
+import 'package:highlights_plugin/method_index.dart' as methods;
 import 'highlights_interface.dart';
 import 'highlights_plugin_platform_interface.dart';
 
 class HighlightsPlugin implements HighlightsInterface {
+  HighlightsPlugin({this.debug = false}) {
+    // Setup before first `instance` getter call
+    HighlightsPluginPlatform.debug = debug;
+  }
+
+  final bool debug;
+
   @override
   Future<List<CodeHighlight>> getHighlights(
     String code,
     String language,
     String theme,
     List<PhraseLocation> emphasisLocations,
-  ) {
-    return HighlightsPluginPlatform.instance.getHighlights(
-      code,
-      language,
-      theme,
-      emphasisLocations,
-    );
+  ) async {
+    try {
+      return await HighlightsPluginPlatform.instance.getHighlights(
+        code,
+        language,
+        theme,
+        emphasisLocations,
+      );
+    } catch (e, st) {
+      _printDebugInfo(methods.getHighlights, e, st);
+      return [];
+    }
   }
 
   @override
-  Future<List<String>> getLanguages() {
-    return HighlightsPluginPlatform.instance.getLanguages();
+  Future<List<String>> getLanguages() async {
+    try {
+      return await HighlightsPluginPlatform.instance.getLanguages();
+    } catch (e, st) {
+      _printDebugInfo(methods.getLanguages, e, st);
+      return [];
+    }
   }
 
+  // TODO Create release 0.0.1 and 0.0.2
   @override
-  Future<List<String>> getThemes() {
-    return HighlightsPluginPlatform.instance.getThemes();
+  Future<List<String>> getThemes() async {
+    try {
+      return await HighlightsPluginPlatform.instance.getThemes();
+    } catch (e, st) {
+      _printDebugInfo(methods.getThemes, e, st);
+      return [];
+    }
+  }
+
+  void _printDebugInfo(String method, Object error, StackTrace stackTrace) {
+    if (debug) {
+      print('HighlightsPlugin $method error: $error');
+      debugPrintStack(stackTrace: stackTrace);
+    }
   }
 }

lib/highlights_plugin_method_channel.dart

@@ -13,12 +13,16 @@ import 'highlights_plugin_platform_interface.dart';
 /// An implementation of [HighlightsPluginPlatform] that uses method channels.
 class MethodChannelHighlightsPlugin extends HighlightsPluginPlatform
     implements HighlightsInterface {
+  MethodChannelHighlightsPlugin({required this.debug});
+
   /// The method channel used to interact with the native platform.
   @visibleForTesting
   final methodChannel = const MethodChannel('highlights_plugin');
 
-  List<String>? _languages;
-  List<String>? _themes;
+  final bool debug;
+
+  List<String>? _cachedLanguages;
+  List<String>? _cachedThemes;
 
   @override
   Future<List<CodeHighlight>> getHighlights(
@@ -44,7 +48,7 @@ class MethodChannelHighlightsPlugin extends HighlightsPluginPlatform
     if (data is List) {
       return data.map((e) => CodeHighlight.fromJson(e)).toList();
     } else {
-      print(
+      _debugPrint(
         '${index.getHighlights}: Expected List but got ${data.runtimeType}',
       );
       return [];
@@ -53,16 +57,16 @@ class MethodChannelHighlightsPlugin extends HighlightsPluginPlatform
 
   @override
   Future<List<String>> getLanguages() async {
-    if (_languages != null) return _languages!;
+    if (_cachedLanguages != null) return _cachedLanguages!;
 
     final result = await methodChannel.invokeMethod(index.getLanguages);
 
     if (result is List) {
       final output = result.map((data) => data.toString()).toList();
-      _languages = output;
+      _cachedLanguages = output;
       return output;
     } else {
-      print(
+      _debugPrint(
         '${index.getLanguages}: Expected List but got ${result.runtimeType}',
       );
       return [];
@@ -71,31 +75,39 @@ class MethodChannelHighlightsPlugin extends HighlightsPluginPlatform
 
   @override
   Future<List<String>> getThemes() async {
-    if (_themes != null) return _themes!;
+    if (_cachedThemes != null) return _cachedThemes!;
 
     final result = await methodChannel.invokeMethod(index.getThemes);
 
     if (result is List) {
       final output = result.map((e) => e.toString()).toList();
-      _themes = output;
+      _cachedThemes = output;
       return output;
     } else {
-      print('${index.getThemes}: Expected List but got ${result.runtimeType}');
+      _debugPrint(
+        '${index.getThemes}: Expected List but got ${result.runtimeType}',
+      );
       return [];
     }
   }
 
   Future<String> _getLanguage(String expected) async {
-    final data = _languages ?? (await getLanguages());
+    final data = _cachedLanguages ?? (await getLanguages());
     final result = data.getMatching(expected);
     return result ?? data.first;
   }
 
   Future<String> _getTheme(String expected) async {
-    final data = _themes ?? (await getThemes());
+    final data = _cachedThemes ?? (await getThemes());
     final result = data.getMatching(expected);
     return result ?? data.first;
   }
+
+  void _debugPrint(String message) {
+    if (debug) {
+      print(message);
+    }
+  }
 }
 
 extension on List<String> {

lib/highlights_plugin_platform_interface.dart

@@ -12,7 +12,10 @@ abstract class HighlightsPluginPlatform extends PlatformInterface
 
   static final Object _token = Object();
 
-  static HighlightsPluginPlatform _instance = MethodChannelHighlightsPlugin();
+  static bool debug = false;
+
+  static HighlightsPluginPlatform _instance =
+      MethodChannelHighlightsPlugin(debug: debug);
 
   /// The default instance of [HighlightsPluginPlatform] to use.
   ///