Bug 1512274 - Enable Checkstyle for GeckoView. r=geckoview-reviewers,nalexander,snorp

Differential Revision: https://phabricator.services.mozilla.com/D23692

--HG--
extra : moz-landing-system : lando

mobile/android/geckoview/build.gradle

@@ -1,6 +1,7 @@
 buildDir "${topobjdir}/gradle/build/mobile/android/geckoview"
 
 apply plugin: 'com.android.library'
+apply plugin: 'checkstyle'
 apply plugin: 'kotlin-android'
 
 apply from: "${topsrcdir}/mobile/android/gradle/product_flavors.gradle"
@@ -297,6 +298,14 @@ android.libraryVariants.all { variant ->
         destinationDir = new File(destinationDir, variant.baseName)
         from files(variant.javaCompile.source)
     }
+
+    task("checkstyle${name.capitalize()}", type: Checkstyle) {
+        classpath = variant.javaCompile.classpath
+        configFile file("checkstyle.xml")
+        // TODO: cleanup and include all sources
+        source = ['src/main/java/']
+        include '**/*.java'
+    }
 }
 
 android.libraryVariants.all { variant ->

mobile/android/geckoview/checkstyle.xml

@@ -0,0 +1,67 @@
+<?xml version="1.0"?>
+<!-- This Source Code Form is subject to the terms of the Mozilla Public
+   - License, v. 2.0. If a copy of the MPL was not distributed with this
+   - file, You can obtain one at http://mozilla.org/MPL/2.0/. -->
+<!DOCTYPE module PUBLIC
+    "-//Puppy Crawl//DTD Check Configuration 1.2//EN"
+    "http://www.puppycrawl.com/dtds/configuration_1_2.dtd">
+
+<module name="Checker">
+    <property name="charset" value="UTF-8"/>
+
+    <!-- Disallow tabs -->
+    <module name="FileTabCharacter">
+        <property name="eachLine" value="true"/>
+    </module>
+
+    <!-- Disallow trailing whitespace -->
+    <module name="RegexpSingleline">
+        <property name="format" value="\s+$"/>
+        <property name="message" value="Trailing whitespace"/>
+    </module>
+
+    <module name="TreeWalker">
+        <module name="FinalParameters"/>
+        <module name="ParameterName"/>
+        <module name="StaticVariableName"/>
+        <module name="LeftCurly"/>
+        <module name="RightCurly"/>
+        <module name="Indentation"/>
+        <module name="OneStatementPerLine"/>
+        <module name="AvoidStarImport"/>
+        <module name="UnusedImports"/>
+
+        <module name="MemberName">
+            <!-- Private members must use mHungarianNotation -->
+            <property name="format" value="m[A-Z][A-Za-z]*$"/>
+            <property name="applyToPrivate" value="true" />
+            <property name="applyToPublic" value="false" />
+            <property name="applyToPackage" value="false" />
+            <property name="applyToProtected" value="false" />
+        </module>
+
+        <module name="ClassTypeParameterName">
+            <property name="format" value="^[A-Z][A-Za-z]*$"/>
+        </module>
+        <module name="InterfaceTypeParameterName">
+            <property name="format" value="^[A-Z][A-Za-z]*$"/>
+        </module>
+        <module name="LocalVariableName"/>
+
+        <module name="GenericWhitespace"/>
+        <module name="NoLineWrap">
+            <property name="tokens" value="IMPORT,PACKAGE_DEF"/>
+        </module>
+        <module name="OuterTypeFilename"/>
+        <module name="WhitespaceAfter">
+            <property name="tokens" value="COMMA, SEMI"/>
+        </module>
+        <module name="WhitespaceAround">
+            <property name="allowEmptyConstructors" value="true"/>
+            <property name="allowEmptyMethods" value="true"/>
+            <property name="allowEmptyTypes" value="true"/>
+        </module>
+        <module name="OneTopLevelClass"/>
+    </module>
+
+</module>

mobile/android/gradle.configure

@@ -236,11 +236,12 @@ def gradle_android_api_lint_tasks(build_config):
 set_config('GRADLE_ANDROID_API_LINT_TASKS', gradle_android_api_lint_tasks)
 
 
-@dependable
-def gradle_android_checkstyle_tasks():
+@depends(gradle_android_build_config)
+def gradle_android_checkstyle_tasks(build_config):
     '''Gradle tasks run by |mach android checkstyle|.'''
     return [
         'app:checkstyle',
+        'geckoview:checkstyle{geckoview.variant.name}'.format(geckoview=build_config.geckoview),
     ]
 
 set_config('GRADLE_ANDROID_CHECKSTYLE_TASKS', gradle_android_checkstyle_tasks)