From e06a8cec65815599e510d7f9c1ea9d2a8eaa438a Mon Sep 17 00:00:00 2001
From: cpovirk <cpovirk@google.com>
Date: Wed, 3 Aug 2022 18:36:27 -0700
Subject: [PATCH] Enable Error Prone for Maven builds.

Fixes https://github.com/google/guava/issues/2484

RELNOTES=n/a
PiperOrigin-RevId: 465199181
---
 .../common/collect/testing/Platform.java      |  2 +-
 .../reflect/TypeTokenResolutionTest.java      |  2 ++
 .../common/reflect/TypeTokenSubtypeTest.java  |  6 ++++
 .../google/common/reflect/TypeTokenTest.java  |  1 +
 android/pom.xml                               | 34 +++++++++++++++++++
 .../common/collect/testing/Platform.java      |  2 +-
 .../reflect/TypeTokenResolutionTest.java      |  2 ++
 .../common/reflect/TypeTokenSubtypeTest.java  |  6 ++++
 .../google/common/reflect/TypeTokenTest.java  |  1 +
 pom.xml                                       | 34 +++++++++++++++++++
 10 files changed, 88 insertions(+), 2 deletions(-)

diff --git a/android/guava-testlib/src/com/google/common/collect/testing/Platform.java b/android/guava-testlib/src/com/google/common/collect/testing/Platform.java
index a2c020c915d4..cfc7ac3b284e 100644
--- a/android/guava-testlib/src/com/google/common/collect/testing/Platform.java
+++ b/android/guava-testlib/src/com/google/common/collect/testing/Platform.java
@@ -34,7 +34,7 @@ static <T> T[] clone(T[] array) {
 
   // Class.cast is not supported in GWT.  This method is a no-op in GWT.
   static void checkCast(Class<?> clazz, Object obj) {
-    clazz.cast(obj);
+    Object unused = clazz.cast(obj);
   }
 
   static String format(String template, Object... args) {
diff --git a/android/guava-tests/test/com/google/common/reflect/TypeTokenResolutionTest.java b/android/guava-tests/test/com/google/common/reflect/TypeTokenResolutionTest.java
index 69e59ff18895..2aa7ae5e8b97 100644
--- a/android/guava-tests/test/com/google/common/reflect/TypeTokenResolutionTest.java
+++ b/android/guava-tests/test/com/google/common/reflect/TypeTokenResolutionTest.java
@@ -178,10 +178,12 @@ public void testResolveNestedClass() {
     assertEquals(String.class, new Owner.Nested<String>() {}.getTypeArgument());
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testResolveInnerClass() {
     assertEquals(String.class, new Owner<Integer>().new Inner<String>() {}.getTypeArgument());
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testResolveOwnerClass() {
     assertEquals(Integer.class, new Owner<Integer>().new Inner<String>() {}.getOwnerType());
   }
diff --git a/android/guava-tests/test/com/google/common/reflect/TypeTokenSubtypeTest.java b/android/guava-tests/test/com/google/common/reflect/TypeTokenSubtypeTest.java
index 0dd2318e9776..4905df74ef18 100644
--- a/android/guava-tests/test/com/google/common/reflect/TypeTokenSubtypeTest.java
+++ b/android/guava-tests/test/com/google/common/reflect/TypeTokenSubtypeTest.java
@@ -47,30 +47,35 @@ public void testRecursiveWildcardSubtypeBug() throws Exception {
     }
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testSubtypeOfInnerClass_nonStaticAnonymousClass() {
     TypeToken<?> supertype = new TypeToken<Mall<Outdoor>.Shop<Electronics>>() {};
     Class<?> subclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
     assertTrue(TypeToken.of(subclass).isSubtypeOf(supertype));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testSubtypeOfInnerClass_nonStaticAnonymousClass_typeParameterOfOwnerTypeNotMatch() {
     TypeToken<?> supertype = new TypeToken<Mall<Outdoor>.Shop<Electronics>>() {};
     Class<?> subclass = new Mall<Indoor>().new Shop<Electronics>() {}.getClass();
     assertFalse(TypeToken.of(subclass).isSubtypeOf(supertype));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testSubtypeOfInnerClass_nonStaticAnonymousClass_typeParameterOfInnerTypeNotMatch() {
     TypeToken<?> supertype = new TypeToken<Mall<Outdoor>.Shop<Electronics>>() {};
     Class<?> subclass = new Mall<Outdoor>().new Shop<Grocery>() {}.getClass();
     assertFalse(TypeToken.of(subclass).isSubtypeOf(supertype));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public static void testSubtypeOfInnerClass_staticAnonymousClass() {
     TypeToken<?> supertype = new TypeToken<Mall<Outdoor>.Shop<Electronics>>() {};
     Class<?> subclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
     assertTrue(TypeToken.of(subclass).isSubtypeOf(supertype));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public static void testSubtypeOfStaticAnonymousClass() {
     Class<?> superclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
     assertTrue(TypeToken.of(superclass).isSubtypeOf(superclass));
@@ -79,6 +84,7 @@ public static void testSubtypeOfStaticAnonymousClass() {
             .isSubtypeOf(superclass));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testSubtypeOfNonStaticAnonymousClass() {
     Class<?> superclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
     assertTrue(TypeToken.of(superclass).isSubtypeOf(superclass));
diff --git a/android/guava-tests/test/com/google/common/reflect/TypeTokenTest.java b/android/guava-tests/test/com/google/common/reflect/TypeTokenTest.java
index cb0dc99404fc..daf348662fea 100644
--- a/android/guava-tests/test/com/google/common/reflect/TypeTokenTest.java
+++ b/android/guava-tests/test/com/google/common/reflect/TypeTokenTest.java
@@ -1747,6 +1747,7 @@ Type type() {
     }
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public <T> void testRejectTypeVariable_withOwnerType() {
     // Neither has subclass
     assertHasTypeVariable(new From<Integer>().new To<String>().type());
diff --git a/android/pom.xml b/android/pom.xml
index 27450e0573a3..1b4a65c0b2ea 100644
--- a/android/pom.xml
+++ b/android/pom.xml
@@ -18,6 +18,7 @@
     <checker-framework.version>3.12.0</checker-framework.version>
     <animal.sniffer.version>1.20</animal.sniffer.version>
     <maven-javadoc-plugin.version>3.1.0</maven-javadoc-plugin.version>
+    <javac.version>9+181-r4173-1</javac.version>
     <!-- Empty for all JDKs but 9-12 -->
     <maven-javadoc-plugin.additionalJOptions></maven-javadoc-plugin.additionalJOptions>
     <maven-source-plugin.version>3.2.1</maven-source-plugin.version>
@@ -122,6 +123,7 @@
           <configuration>
             <source>1.8</source>
             <target>1.8</target>
+            <encoding>UTF-8</encoding>
             <compilerArgs>
               <!--
                    Make includes/excludes fully work:
@@ -131,7 +133,18 @@
               -->
               <arg>-sourcepath</arg>
               <arg>doesnotexist</arg>
+              <!-- https://errorprone.info/docs/installation#maven -->
+              <arg>-XDcompilePolicy=simple</arg>
+              <arg>-Xplugin:ErrorProne</arg>
             </compilerArgs>
+            <annotationProcessorPaths>
+              <path>
+                <groupId>com.google.errorprone</groupId>
+                <artifactId>error_prone_core</artifactId>
+                <!-- https://errorprone.info/docs/installation#jdk-8 -->
+                <version>2.10.0</version>
+              </path>
+            </annotationProcessorPaths>
           </configuration>
         </plugin>
         <plugin>
@@ -427,5 +440,26 @@
         </test.add.opens>
       </properties>
     </profile>
+    <!-- https://github.com/google/error-prone/blob/f8e33bc460be82ab22256a7ef8b979d7a2cacaba/docs/installation.md#jdk-8 -->
+    <profile>
+      <id>jdk8</id>
+      <activation>
+        <jdk>1.8</jdk>
+      </activation>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <configuration>
+              <fork>true</fork>
+              <compilerArgs combine.children="append">
+                <arg>-J-Xbootclasspath/p:${settings.localRepository}/com/google/errorprone/javac/${javac.version}/javac-${javac.version}.jar</arg>
+              </compilerArgs>
+            </configuration>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
   </profiles>
 </project>
diff --git a/guava-testlib/src/com/google/common/collect/testing/Platform.java b/guava-testlib/src/com/google/common/collect/testing/Platform.java
index a2c020c915d4..cfc7ac3b284e 100644
--- a/guava-testlib/src/com/google/common/collect/testing/Platform.java
+++ b/guava-testlib/src/com/google/common/collect/testing/Platform.java
@@ -34,7 +34,7 @@ static <T> T[] clone(T[] array) {
 
   // Class.cast is not supported in GWT.  This method is a no-op in GWT.
   static void checkCast(Class<?> clazz, Object obj) {
-    clazz.cast(obj);
+    Object unused = clazz.cast(obj);
   }
 
   static String format(String template, Object... args) {
diff --git a/guava-tests/test/com/google/common/reflect/TypeTokenResolutionTest.java b/guava-tests/test/com/google/common/reflect/TypeTokenResolutionTest.java
index 69e59ff18895..2aa7ae5e8b97 100644
--- a/guava-tests/test/com/google/common/reflect/TypeTokenResolutionTest.java
+++ b/guava-tests/test/com/google/common/reflect/TypeTokenResolutionTest.java
@@ -178,10 +178,12 @@ public void testResolveNestedClass() {
     assertEquals(String.class, new Owner.Nested<String>() {}.getTypeArgument());
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testResolveInnerClass() {
     assertEquals(String.class, new Owner<Integer>().new Inner<String>() {}.getTypeArgument());
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testResolveOwnerClass() {
     assertEquals(Integer.class, new Owner<Integer>().new Inner<String>() {}.getOwnerType());
   }
diff --git a/guava-tests/test/com/google/common/reflect/TypeTokenSubtypeTest.java b/guava-tests/test/com/google/common/reflect/TypeTokenSubtypeTest.java
index 0dd2318e9776..4905df74ef18 100644
--- a/guava-tests/test/com/google/common/reflect/TypeTokenSubtypeTest.java
+++ b/guava-tests/test/com/google/common/reflect/TypeTokenSubtypeTest.java
@@ -47,30 +47,35 @@ public void testRecursiveWildcardSubtypeBug() throws Exception {
     }
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testSubtypeOfInnerClass_nonStaticAnonymousClass() {
     TypeToken<?> supertype = new TypeToken<Mall<Outdoor>.Shop<Electronics>>() {};
     Class<?> subclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
     assertTrue(TypeToken.of(subclass).isSubtypeOf(supertype));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testSubtypeOfInnerClass_nonStaticAnonymousClass_typeParameterOfOwnerTypeNotMatch() {
     TypeToken<?> supertype = new TypeToken<Mall<Outdoor>.Shop<Electronics>>() {};
     Class<?> subclass = new Mall<Indoor>().new Shop<Electronics>() {}.getClass();
     assertFalse(TypeToken.of(subclass).isSubtypeOf(supertype));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testSubtypeOfInnerClass_nonStaticAnonymousClass_typeParameterOfInnerTypeNotMatch() {
     TypeToken<?> supertype = new TypeToken<Mall<Outdoor>.Shop<Electronics>>() {};
     Class<?> subclass = new Mall<Outdoor>().new Shop<Grocery>() {}.getClass();
     assertFalse(TypeToken.of(subclass).isSubtypeOf(supertype));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public static void testSubtypeOfInnerClass_staticAnonymousClass() {
     TypeToken<?> supertype = new TypeToken<Mall<Outdoor>.Shop<Electronics>>() {};
     Class<?> subclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
     assertTrue(TypeToken.of(subclass).isSubtypeOf(supertype));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public static void testSubtypeOfStaticAnonymousClass() {
     Class<?> superclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
     assertTrue(TypeToken.of(superclass).isSubtypeOf(superclass));
@@ -79,6 +84,7 @@ public static void testSubtypeOfStaticAnonymousClass() {
             .isSubtypeOf(superclass));
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public void testSubtypeOfNonStaticAnonymousClass() {
     Class<?> superclass = new Mall<Outdoor>().new Shop<Electronics>() {}.getClass();
     assertTrue(TypeToken.of(superclass).isSubtypeOf(superclass));
diff --git a/guava-tests/test/com/google/common/reflect/TypeTokenTest.java b/guava-tests/test/com/google/common/reflect/TypeTokenTest.java
index cb0dc99404fc..daf348662fea 100644
--- a/guava-tests/test/com/google/common/reflect/TypeTokenTest.java
+++ b/guava-tests/test/com/google/common/reflect/TypeTokenTest.java
@@ -1747,6 +1747,7 @@ Type type() {
     }
   }
 
+  @SuppressWarnings("RestrictedApiChecker") // crashes under JDK8, which EP no longer supports
   public <T> void testRejectTypeVariable_withOwnerType() {
     // Neither has subclass
     assertHasTypeVariable(new From<Integer>().new To<String>().type());
diff --git a/pom.xml b/pom.xml
index 143c649e9bfb..eb4ab9317906 100644
--- a/pom.xml
+++ b/pom.xml
@@ -18,6 +18,7 @@
     <checker-framework.version>3.12.0</checker-framework.version>
     <animal.sniffer.version>1.20</animal.sniffer.version>
     <maven-javadoc-plugin.version>3.1.0</maven-javadoc-plugin.version>
+    <javac.version>9+181-r4173-1</javac.version>
     <!-- Empty for all JDKs but 9-12 -->
     <maven-javadoc-plugin.additionalJOptions></maven-javadoc-plugin.additionalJOptions>
     <maven-source-plugin.version>3.2.1</maven-source-plugin.version>
@@ -123,6 +124,7 @@
           <configuration>
             <source>1.8</source>
             <target>1.8</target>
+            <encoding>UTF-8</encoding>
             <compilerArgs>
               <!--
                    Make includes/excludes fully work:
@@ -132,7 +134,18 @@
               -->
               <arg>-sourcepath</arg>
               <arg>doesnotexist</arg>
+              <!-- https://errorprone.info/docs/installation#maven -->
+              <arg>-XDcompilePolicy=simple</arg>
+              <arg>-Xplugin:ErrorProne</arg>
             </compilerArgs>
+            <annotationProcessorPaths>
+              <path>
+                <groupId>com.google.errorprone</groupId>
+                <artifactId>error_prone_core</artifactId>
+                <!-- https://errorprone.info/docs/installation#jdk-8 -->
+                <version>2.10.0</version>
+              </path>
+            </annotationProcessorPaths>
           </configuration>
         </plugin>
         <plugin>
@@ -434,5 +447,26 @@
         </test.add.opens>
       </properties>
     </profile>
+    <!-- https://github.com/google/error-prone/blob/f8e33bc460be82ab22256a7ef8b979d7a2cacaba/docs/installation.md#jdk-8 -->
+    <profile>
+      <id>jdk8</id>
+      <activation>
+        <jdk>1.8</jdk>
+      </activation>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <configuration>
+              <fork>true</fork>
+              <compilerArgs combine.children="append">
+                <arg>-J-Xbootclasspath/p:${settings.localRepository}/com/google/errorprone/javac/${javac.version}/javac-${javac.version}.jar</arg>
+              </compilerArgs>
+            </configuration>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
   </profiles>
 </project>