[pigeon] implemented primitive datatypes

packages/pigeon/CHANGELOG.md

@@ -4,6 +4,7 @@
 * [front-end] Added a more explicit error for static fields.
 * [front-end] Added more errors for incorrect usage of Pigeon (previously they were just ignored).
 * Moved Pigeon to using a custom codec which allows collection types to contain custom classes.
+* Started allowing primitive data types as arguments and return types.
 
 ## 0.3.0
 

packages/pigeon/lib/dart_generator.dart

@@ -121,19 +121,14 @@ final BinaryMessenger$nullTag _binaryMessenger;
       }
       String argSignature = '';
       String sendArgument = 'null';
-      String? encodedDeclaration;
       if (func.argType != 'void') {
         argSignature = '${func.argType} arg';
-        sendArgument = 'encoded';
-        encodedDeclaration = 'final Object encoded = arg.encode();';
+        sendArgument = 'arg';
       }
       indent.write(
         'Future<${func.returnType}> ${func.name}($argSignature) async ',
       );
       indent.scoped('{', '}', () {
-        if (encodedDeclaration != null) {
-          indent.writeln(encodedDeclaration);
-        }
         final String channelName = makeChannelName(api, func);
         indent.writeln(
             'final BasicMessageChannel<Object$nullTag> channel = BasicMessageChannel<Object$nullTag>(');
@@ -144,7 +139,7 @@ final BinaryMessenger$nullTag _binaryMessenger;
         });
         final String returnStatement = func.returnType == 'void'
             ? '// noop'
-            : 'return ${func.returnType}.decode(replyMap[\'${Keys.result}\']$unwrapOperator);';
+            : 'return (replyMap[\'${Keys.result}\'] as ${func.returnType}$nullTag)$unwrapOperator;';
         indent.format('''
 final Map<Object$nullTag, Object$nullTag>$nullTag replyMap =\n\t\tawait channel.send($sendArgument) as Map<Object$nullTag, Object$nullTag>$nullTag;
 if (replyMap == null) {
@@ -237,7 +232,7 @@ void _writeFlutterApi(
                   'assert(message != null, \'Argument for $channelName was null. Expected $argType.\');',
                 );
                 indent.writeln(
-                  'final $argType input = $argType.decode(message$unwrapOperator);',
+                  'final $argType input = (message as $argType$nullTag)$unwrapOperator;',
                 );
                 call = 'api.${func.name}(input)';
               }
@@ -254,7 +249,7 @@ void _writeFlutterApi(
                 } else {
                   indent.writeln('final $returnType output = $call;');
                 }
-                const String returnExpression = 'output.encode()';
+                const String returnExpression = 'output';
                 final String returnStatement = isMockHandler
                     ? 'return <Object$nullTag, Object$nullTag>{\'${Keys.result}\': $returnExpression};'
                     : 'return $returnExpression;';

packages/pigeon/lib/generator_tools.dart

@@ -262,6 +262,20 @@ class EnumeratedClass {
   final int enumeration;
 }
 
+/// Supported basic datatypes.
+const List<String> validTypes = <String>[
+  'String',
+  'bool',
+  'int',
+  'double',
+  'Uint8List',
+  'Int32List',
+  'Int64List',
+  'Float64List',
+  'List',
+  'Map',
+];
+
 /// Custom codecs' custom types are enumerated from 255 down to this number to
 /// avoid collisions with the StandardMessageCodec.
 const int _minimumCodecFieldKey = 128;
@@ -274,8 +288,10 @@ Iterable<EnumeratedClass> getCodecClasses(Api api) sync* {
     names.add(method.returnType);
     names.add(method.argType);
   }
-  final List<String> sortedNames =
-      names.where((String element) => element != 'void').toList();
+  final List<String> sortedNames = names
+      .where((String element) =>
+          element != 'void' && !validTypes.contains(element))
+      .toList();
   sortedNames.sort();
   int enumeration = _minimumCodecFieldKey;
   const int maxCustomClassesPerApi = 255 - _minimumCodecFieldKey;

packages/pigeon/lib/java_generator.dart

@@ -113,6 +113,22 @@ void _writeCodec(Indent indent, Api api) {
   });
 }
 
+/// This performs Dart to Java type conversions.  If performs a passthrough of
+/// the input if it can't be converted.
+// TODO(gaaclarke): Remove this method and unify it with `_javaTypeForDartType`.
+String _javaTypeForDartTypePassthrough(String type) {
+  const Map<String, String> map = <String, String>{
+    'int': 'Integer',
+    'bool': 'Boolean',
+    'double': 'Double',
+    'Int32List': 'int[]',
+    'Uint8List': 'byte[]',
+    'Int64List': 'long[]',
+    'Float64List': 'double[]',
+  };
+  return map[type] ?? type;
+}
+
 void _writeHostApi(Indent indent, Api api) {
   assert(api.location == ApiLocation.host);
 
@@ -121,11 +137,13 @@ void _writeHostApi(Indent indent, Api api) {
   indent.write('public interface ${api.name} ');
   indent.scoped('{', '}', () {
     for (final Method method in api.methods) {
-      final String returnType =
-          method.isAsynchronous ? 'void' : method.returnType;
+      final String argType = _javaTypeForDartTypePassthrough(method.argType);
+      final String returnType = method.isAsynchronous
+          ? 'void'
+          : _javaTypeForDartTypePassthrough(method.returnType);
       final List<String> argSignature = <String>[];
       if (method.argType != 'void') {
-        argSignature.add('${method.argType} arg');
+        argSignature.add('$argType arg');
       }
       if (method.isAsynchronous) {
         final String returnType =
@@ -162,21 +180,27 @@ static MessageCodec<Object> getCodec() {
           indent.scoped('{', '} else {', () {
             indent.write('channel.setMessageHandler((message, reply) -> ');
             indent.scoped('{', '});', () {
-              final String argType = method.argType;
-              final String returnType = method.returnType;
+              final String argType =
+                  _javaTypeForDartTypePassthrough(method.argType);
+              final String returnType =
+                  _javaTypeForDartTypePassthrough(method.returnType);
               indent.writeln('Map<String, Object> wrapped = new HashMap<>();');
               indent.write('try ');
               indent.scoped('{', '}', () {
                 final List<String> methodArgument = <String>[];
                 if (argType != 'void') {
                   indent.writeln('@SuppressWarnings("ConstantConditions")');
-                  indent.writeln(
-                      '$argType input = $argType.fromMap((Map<String, Object>)message);');
+                  indent.writeln('$argType input = ($argType)message;');
+                  indent.write('if (input == null) ');
+                  indent.scoped('{', '}', () {
+                    indent.writeln(
+                        'throw new NullPointerException("Message unexpectedly null.");');
+                  });
                   methodArgument.add('input');
                 }
                 if (method.isAsynchronous) {
                   final String resultValue =
-                      method.returnType == 'void' ? 'null' : 'result.toMap()';
+                      method.returnType == 'void' ? 'null' : 'result';
                   methodArgument.add(
                     'result -> { '
                     'wrapped.put("${Keys.result}", $resultValue); '
@@ -193,8 +217,7 @@ static MessageCodec<Object> getCodec() {
                   indent.writeln('wrapped.put("${Keys.result}", null);');
                 } else {
                   indent.writeln('$returnType output = $call;');
-                  indent.writeln(
-                      'wrapped.put("${Keys.result}", output.toMap());');
+                  indent.writeln('wrapped.put("${Keys.result}", output);');
                 }
               });
               indent.write('catch (Error | RuntimeException exception) ');
@@ -242,16 +265,18 @@ static MessageCodec<Object> getCodec() {
 ''');
     for (final Method func in api.methods) {
       final String channelName = makeChannelName(api, func);
-      final String returnType =
-          func.returnType == 'void' ? 'Void' : func.returnType;
+      final String returnType = func.returnType == 'void'
+          ? 'Void'
+          : _javaTypeForDartTypePassthrough(func.returnType);
+      final String argType = _javaTypeForDartTypePassthrough(func.argType);
       String sendArgument;
       if (func.argType == 'void') {
         indent.write('public void ${func.name}(Reply<$returnType> callback) ');
         sendArgument = 'null';
       } else {
         indent.write(
-            'public void ${func.name}(${func.argType} argInput, Reply<$returnType> callback) ');
-        sendArgument = 'inputMap';
+            'public void ${func.name}($argType argInput, Reply<$returnType> callback) ');
+        sendArgument = 'argInput';
       }
       indent.scoped('{', '}', () {
         indent.writeln('BasicMessageChannel<Object> channel =');
@@ -261,18 +286,13 @@ static MessageCodec<Object> getCodec() {
             'new BasicMessageChannel<>(binaryMessenger, "$channelName", getCodec());');
         indent.dec();
         indent.dec();
-        if (func.argType != 'void') {
-          indent.writeln('Map<String, Object> inputMap = argInput.toMap();');
-        }
         indent.write('channel.send($sendArgument, channelReply -> ');
         indent.scoped('{', '});', () {
           if (func.returnType == 'void') {
             indent.writeln('callback.reply(null);');
           } else {
-            indent.writeln('Map outputMap = (Map)channelReply;');
             indent.writeln('@SuppressWarnings("ConstantConditions")');
-            indent.writeln(
-                '${func.returnType} output = ${func.returnType}.fromMap(outputMap);');
+            indent.writeln('$returnType output = ($returnType)channelReply;');
             indent.writeln('callback.reply(output);');
           }
         });