[pigeon] Added error-prone to CI and fixed its issue. (#312)

packages/pigeon/CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.1.23
+
+* More Java linter and linter fixes.
+
 ## 0.1.22
 
 * Java code generator enhancements:

packages/pigeon/ci/.gitignore

@@ -0,0 +1 @@
+*

packages/pigeon/lib/dart_generator.dart

@@ -65,9 +65,9 @@ if (replyMap == null) {
 \t\tdetails: null,
 \t);
 } else if (replyMap['error'] != null) {
-\tfinal Map<Object$nullTag, Object$nullTag> error = replyMap['${Keys.error}'] as Map<Object$nullTag, Object$nullTag>;
+\tfinal Map<Object$nullTag, Object$nullTag> error = (replyMap['${Keys.error}'] as Map<Object$nullTag, Object$nullTag>$nullTag)$unwrapOperator;
 \tthrow PlatformException(
-\t\tcode: error['${Keys.errorCode}'] as String,
+\t\tcode: (error['${Keys.errorCode}'] as String$nullTag)$unwrapOperator,
 \t\tmessage: error['${Keys.errorMessage}'] as String$nullTag,
 \t\tdetails: error['${Keys.errorDetails}'],
 \t);
@@ -161,10 +161,10 @@ void _writeFlutterApi(
                 } else {
                   indent.writeln('final $returnType output = $call;');
                 }
-                const String returnExpresion = 'output.encode()';
+                const String returnExpression = 'output.encode()';
                 final String returnStatement = isMockHandler
-                    ? 'return <Object$nullTag, Object$nullTag>{\'${Keys.result}\': $returnExpresion};'
+                    ? 'return <Object$nullTag, Object$nullTag>{\'${Keys.result}\': $returnExpression};'
-                    : 'return $returnExpresion;';
+                    : 'return $returnExpression;';
                 indent.writeln(returnStatement);
               }
             });
@@ -197,7 +197,7 @@ void generateDart(DartOptions opt, Root root, StringSink sink) {
   indent.writeln('// $generatedCodeWarning');
   indent.writeln('// $seeAlsoWarning');
   indent.writeln(
-    '// ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import',
+    '// ignore_for_file: public_member_api_docs, non_constant_identifier_names, avoid_as, unused_import, unnecessary_parenthesis, prefer_null_aware_operators',
   );
   indent.writeln('// @dart = ${opt.isNullSafe ? '2.12' : '2.8'}');
   indent.writeln('import \'dart:async\';');

packages/pigeon/lib/generator_tools.dart

@@ -8,7 +8,7 @@ import 'dart:mirrors';
 import 'ast.dart';
 
 /// The current version of pigeon. This must match the version in pubspec.yaml.
-const String pigeonVersion = '0.1.22';
+const String pigeonVersion = '0.1.23';
 
 /// Read all the content from [stdin] to a String.
 String readStdin() {

packages/pigeon/lib/java_generator.dart

@@ -56,7 +56,7 @@ void _writeHostApi(Indent indent, Api api) {
     }
     indent.addln('');
     indent.writeln(
-        '/** Sets up an instance of `${api.name}` to handle messages through the `binaryMessenger` */');
+        '/** Sets up an instance of `${api.name}` to handle messages through the `binaryMessenger`. */');
     indent.write(
         'static void setup(BinaryMessenger binaryMessenger, ${api.name} api) ');
     indent.scoped('{', '}', () {
@@ -108,7 +108,7 @@ void _writeHostApi(Indent indent, Api api) {
                       'wrapped.put("${Keys.result}", output.toMap());');
                 }
               });
-              indent.write('catch (Exception exception) ');
+              indent.write('catch (Error | RuntimeException exception) ');
               indent.scoped('{', '}', () {
                 indent.writeln(
                     'wrapped.put("${Keys.error}", wrapError(exception));');
@@ -298,7 +298,7 @@ void generateJava(JavaOptions options, Root root, StringSink sink) {
     }
 
     indent.format('''
-private static Map<String, Object> wrapError(Exception exception) {
+private static Map<String, Object> wrapError(Throwable exception) {
 \tMap<String, Object> errorMap = new HashMap<>();
 \terrorMap.put("${Keys.errorMessage}", exception.toString());
 \terrorMap.put("${Keys.errorCode}", exception.getClass().getSimpleName());

packages/pigeon/lib/pigeon_lib.dart

@@ -305,7 +305,7 @@ options:
     ..addOption('objc_prefix',
         help: 'Prefix for generated Objective-C classes and protocols.');
 
-  /// Convert command-line arugments to [PigeonOptions].
+  /// Convert command-line arguments to [PigeonOptions].
   static PigeonOptions parseArgs(List<String> args) {
     final ArgResults results = _argParser.parse(args);
 

packages/pigeon/pubspec.yaml

@@ -1,5 +1,5 @@
 name: pigeon
-version: 0.1.22 # This must match the version in lib/generator_tools.dart
+version: 0.1.23 # This must match the version in lib/generator_tools.dart
 description: Code generator tool to make communication between Flutter and the host platform type-safe and easier.
 homepage: https://github.com/flutter/packages/tree/master/packages/pigeon
 dependencies:

packages/pigeon/run_tests.sh

@@ -11,6 +11,16 @@ set -ex
 JAVA_LINTER=checkstyle-8.41-all.jar
 JAVA_FORMATTER=google-java-format-1.3-all-deps.jar
 GOOGLE_CHECKS=google_checks.xml
+JAVA_ERROR_PRONE=error_prone_core-2.5.1-with-dependencies.jar
+DATAFLOW_SHADED=dataflow-shaded-3.7.1.jar
+JFORMAT_STRING=jFormatString-3.0.0.jar
+JAVA_VERSION=$(java -version 2>&1 | head -1 | cut -d'"' -f2 | sed '/^1\./s///' | cut -d'.' -f1)
+JAVAC_JAR=javac-9+181-r4173-1.jar
+if [ $JAVA_VERSION == "8" ]; then
+  JAVAC_BOOTCLASSPATH="-J-Xbootclasspath/p:ci/$JAVAC_JAR"
+else
+  JAVAC_BOOTCLASSPATH=
+fi
 
 # TODO(blasten): Enable on stable when possible.
 # https://github.com/flutter/flutter/issues/75187
@@ -72,17 +82,21 @@ test_pigeon_android() {
     --input $1 \
     --dart_out $temp_dir/pigeon.dart \
     --java_out $temp_dir/Pigeon.java \
+    --java_package foo
 
-  if ! javac $temp_dir/Pigeon.java \
+  java -jar ci/$JAVA_FORMATTER --replace "$temp_dir/Pigeon.java"
-      -Xlint:unchecked \
+  java -jar ci/$JAVA_LINTER -c "ci/$GOOGLE_CHECKS" "$temp_dir/Pigeon.java"
-      -classpath "$flutter_bin/cache/artifacts/engine/android-x64/flutter.jar"; then
+  if ! javac \
+    $JAVAC_BOOTCLASSPATH \
+    -XDcompilePolicy=simple \
+    -processorpath "ci/$JAVA_ERROR_PRONE:ci/$DATAFLOW_SHADED:ci/$JFORMAT_STRING" \
+    '-Xplugin:ErrorProne -Xep:CatchingUnchecked:ERROR' \
+    -classpath "$flutter_bin/cache/artifacts/engine/android-x64/flutter.jar" \
+    $temp_dir/Pigeon.java; then
     echo "javac $temp_dir/Pigeon.java failed"
     exit 1
   fi
 
-  java -jar $JAVA_FORMATTER $temp_dir/Pigeon.java > $temp_dir/Pigeon.java
-  java -jar $JAVA_LINTER -c $GOOGLE_CHECKS $temp_dir/Pigeon.java
-
   dartfmt -w $temp_dir/pigeon.dart
   dartanalyzer $temp_dir/pigeon.dart --fatal-infos --fatal-warnings --packages ./e2e_tests/test_objc/.packages
 
@@ -108,15 +122,28 @@ test_null_safe_dart() {
 ###############################################################################
 # Get java linter / formatter
 ###############################################################################
-if [ ! -f "$JAVA_LINTER" ]; then
+if [ ! -f "ci/$JAVA_LINTER" ]; then
-  curl -L https://github.com/checkstyle/checkstyle/releases/download/checkstyle-8.41/$JAVA_LINTER > $JAVA_LINTER
+  curl -L https://github.com/checkstyle/checkstyle/releases/download/checkstyle-8.41/$JAVA_LINTER > "ci/$JAVA_LINTER"
 fi
-if [ ! -f "$JAVA_FORMATTER" ]; then
+if [ ! -f "ci/$JAVA_FORMATTER" ]; then
-  curl -L https://github.com/google/google-java-format/releases/download/google-java-format-1.3/$JAVA_FORMATTER > $JAVA_FORMATTER
+  curl -L https://github.com/google/google-java-format/releases/download/google-java-format-1.3/$JAVA_FORMATTER > "ci/$JAVA_FORMATTER"
 fi
-if [ ! -f "$GOOGLE_CHECKS" ]; then
+if [ ! -f "ci/$GOOGLE_CHECKS" ]; then
-  curl -L https://raw.githubusercontent.com/checkstyle/checkstyle/master/src/main/resources/$GOOGLE_CHECKS > $GOOGLE_CHECKS
+  curl -L https://raw.githubusercontent.com/checkstyle/checkstyle/master/src/main/resources/$GOOGLE_CHECKS > "ci/$GOOGLE_CHECKS"
 fi
+if [ ! -f "ci/$JAVA_ERROR_PRONE" ]; then
+  curl https://repo1.maven.org/maven2/com/google/errorprone/error_prone_core/2.5.1/$JAVA_ERROR_PRONE > "ci/$JAVA_ERROR_PRONE"
+fi
+if [ ! -f "ci/$DATAFLOW_SHADED" ]; then
+  curl https://repo1.maven.org/maven2/org/checkerframework/dataflow-shaded/3.7.1/$DATAFLOW_SHADED > "ci/$DATAFLOW_SHADED"
+fi
+if [ ! -f "ci/$JFORMAT_STRING" ]; then
+  curl https://repo1.maven.org/maven2/com/google/code/findbugs/jFormatString/3.0.0/$JFORMAT_STRING > "ci/$JFORMAT_STRING"
+fi
+if [ ! -f "ci/$JAVAC_JAR" ]; then
+  curl https://repo1.maven.org/maven2/com/google/errorprone/javac/9+181-r4173-1/$JAVAC_JAR > "ci/$JAVAC_JAR"
+fi
+
 
 ###############################################################################
 # Dart analysis and unit tests

packages/pigeon/test/pigeon_lib_test.dart

@@ -238,7 +238,7 @@ void main() {
     expect(results.errors.length, 1);
   });
 
-  test('null saftey flag', () {
+  test('null safety flag', () {
     final PigeonOptions results =
         Pigeon.parseArgs(<String>['--dart_null_safety']);
     expect(results.dartOptions.isNullSafe, true);