Upgrade Error Prone to 2.4.0.

This is both the version targeted by NullAway, as well as the
one used to check NullAway's code for issues.

Due to `ErrorProneCompiler` being deleted upstream and replaced with
`ErrorProneJavaCompiler` (which has a different interface), this PR
also removes `compile-bench`, which we don't believe is under active
use.

build.gradle

@@ -48,13 +48,16 @@ subprojects { project ->
     project.tasks.withType(JavaCompile) {
         dependsOn(installGitHooks)
         options.compilerArgs += [
-            "-Xlint:unchecked",
+            "-Xlint:deprecation",
             "-Xlint:rawtypes",
+            "-Xlint:unchecked",
             "-Werror"
         ]
         options.errorprone {
             // disable warnings in generated code; AutoValue code fails UnnecessaryParentheses check
             disableWarningsInGeneratedCode = true
+            // Triggers for generated Android code (R.java)
+            check("MutablePublicArray", CheckSeverity.OFF)
             // this check is too noisy
             check("StringSplitter", CheckSeverity.OFF)
             check("WildcardImport", CheckSeverity.ERROR)

gradle/dependencies.gradle

@@ -17,8 +17,8 @@
 def versions = [
     asm                    : "7.1",
     checkerFramework       : "3.0.0",
-    errorProne             : "2.3.3", // The version of error prone running on this project
-    errorProneApi          : "2.3.1", // The version of error prone built against and shipped
+    errorProne             : "2.4.0", // The version of error prone running on this project
+    errorProneApi          : "2.4.0", // The version of error prone built against and shipped
     support                : "27.1.1",
     wala                   : "1.5.4",
     commonscli             : "1.4",

jar-infer/jar-infer-lib/src/main/java/com/uber/nullaway/jarinfer/BytecodeAnnotator.java

@@ -193,7 +193,7 @@ private static void annotateBytecode(
    * @param nonnullParams Map from methods to their nonnull params.
    * @param nullableReturns List of methods that return nullable.
    * @param debug flag to output debug logs.
-   * @throws IOException
+   * @throws IOException if an error happens when reading or writing to class streams.
    */
   public static void annotateBytecodeInClass(
       InputStream is,
@@ -262,8 +262,9 @@ private static void copyAndAnnotateJarEntry(
    * @param nonnullParams Map from methods to their nonnull params.
    * @param nullableReturns List of methods that return nullable.
    * @param debug flag to output debug logs.
-   * @throws IOException
+   * @throws IOException if an error happens when reading or writing to jar or class streams.
    */
+  @SuppressWarnings("JdkObsolete")
   public static void annotateBytecodeInJar(
       JarFile inputJar,
       JarOutputStream jarOS,
@@ -302,8 +303,9 @@ public static void annotateBytecodeInJar(
    * @param nonnullParams Map from methods to their nonnull params.
    * @param nullableReturns List of methods that return nullable.
    * @param debug flag to output debug logs.
-   * @throws IOException
+   * @throws IOException if an error happens when reading or writing to AAR/JAR/class streams.
    */
+  @SuppressWarnings("JdkObsolete")
   public static void annotateBytecodeInAar(
       ZipFile inputZip,
       ZipOutputStream zipOS,

jar-infer/jar-infer-lib/src/main/java/com/uber/nullaway/jarinfer/DefinitelyDerefedParams.java

@@ -99,7 +99,7 @@ private static void LOG(boolean cond, String tag, String msg) {
   /**
    * This is the core analysis that identifies definitely-dereferenced parameters.
    *
-   * @return Set<Integer> The ordinal indices of formal parameters that are definitely-dereferenced.
+   * @return The ordinal indices of formal parameters that are definitely-dereferenced.
    */
   Set<Integer> analyze() {
     // Get ExceptionPrunedCFG

jar-infer/jar-infer-lib/src/test/java/com/uber/nullaway/jarinfer/AnnotationChecker.java

@@ -48,8 +48,9 @@ public class AnnotationChecker {
    *     that are expected to be present.
    * @return True when the actual annotations that are expected to be present are present iff the
    *     'Expect*' annotations are present.
-   * @throws IOException
+   * @throws IOException if an error happens when reading the AAR file.
    */
+  @SuppressWarnings("JdkObsolete")
   public static boolean checkMethodAnnotationsInAar(
       String aarFile, Map<String, String> expectedToActualAnnotations) throws IOException {
     Preconditions.checkArgument(aarFile.endsWith(".aar"), "invalid aar file: " + aarFile);
@@ -83,8 +84,9 @@ public static boolean checkMethodAnnotationsInAar(
    *     that are expected to be present.
    * @return True when the actual annotations that are expected to be present are present iff the
    *     'Expect*' annotations are present.
-   * @throws IOException
+   * @throws IOException if an error happens when reading the jar file.
    */
+  @SuppressWarnings("JdkObsolete")
   public static boolean checkMethodAnnotationsInJar(
       String jarFile, Map<String, String> expectedToActualAnnotations) throws IOException {
     Preconditions.checkArgument(jarFile.endsWith(".jar"), "invalid jar file: " + jarFile);

jar-infer/jar-infer-lib/src/test/java/com/uber/nullaway/jarinfer/CompilerUtil.java

@@ -19,11 +19,11 @@
 
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
-import com.google.errorprone.BaseErrorProneCompiler;
+import com.google.errorprone.BaseErrorProneJavaCompiler;
+import com.google.errorprone.DiagnosticTestHelper;
 import com.google.errorprone.ErrorProneInMemoryFileManager;
 import com.google.errorprone.bugpatterns.BugChecker;
 import com.google.errorprone.scanner.ScannerSupplier;
-import com.sun.tools.javac.main.Main;
 import java.io.BufferedWriter;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
@@ -33,6 +33,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import javax.tools.JavaCompiler;
 import javax.tools.JavaFileObject;
 import javax.tools.StandardLocation;
 
@@ -54,8 +55,9 @@ public class CompilerUtil {
 
   private final ErrorProneInMemoryFileManager fileManager;
   private final List<JavaFileObject> sources = new ArrayList<>();
-  private final BaseErrorProneCompiler compiler;
+  private final BaseErrorProneJavaCompiler compiler;
   private final ByteArrayOutputStream outputStream;
+  private final DiagnosticTestHelper diagnosticHelper;
   private List<String> args = ImmutableList.of();
 
   public CompilerUtil(Class<?> klass) {
@@ -66,15 +68,11 @@ public CompilerUtil(Class<?> klass) {
       throw new RuntimeException("unexpected IOException", e);
     }
     outputStream = new ByteArrayOutputStream();
+    diagnosticHelper = new DiagnosticTestHelper();
     this.compiler =
-        BaseErrorProneCompiler.builder()
-            .redirectOutputTo(
-                new PrintWriter(
-                    new BufferedWriter(new OutputStreamWriter(outputStream, UTF_8)), true))
-            .report(
-                ScannerSupplier.fromBugCheckerClasses(
-                    Collections.<Class<? extends BugChecker>>emptySet()))
-            .build();
+        new BaseErrorProneJavaCompiler(
+            ScannerSupplier.fromBugCheckerClasses(
+                Collections.<Class<? extends BugChecker>>emptySet()));
   }
   /**
    * Adds a source file to the test compilation, from an existing resource file.
@@ -100,8 +98,18 @@ public CompilerUtil setArgs(List<String> args) {
     return this;
   }
 
-  private Main.Result compile(Iterable<JavaFileObject> sources, String[] args) {
-    return compiler.run(args, fileManager, ImmutableList.copyOf(sources), null);
+  private boolean compile(Iterable<JavaFileObject> sources, Iterable<String> args) {
+    PrintWriter writer =
+        new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream, UTF_8)), true);
+    JavaCompiler.CompilationTask task =
+        compiler.getTask(
+            writer,
+            fileManager,
+            diagnosticHelper.collector,
+            args,
+            null,
+            ImmutableList.copyOf(sources));
+    return task.call();
   }
 
   public String getOutput() {
@@ -130,9 +138,9 @@ private static List<String> disableImplicitProcessing(List<String> args) {
     return ImmutableList.<String>builder().addAll(args).add("-proc:none").build();
   }
 
-  public Main.Result run() {
+  public boolean run() {
     Preconditions.checkState(!sources.isEmpty(), "No source files to compile");
     List<String> allArgs = buildArguments(args);
-    return compile(sources, allArgs.toArray(new String[allArgs.size()]));
+    return compile(sources, allArgs);
   }
 }

jar-infer/jar-infer-lib/src/test/java/com/uber/nullaway/jarinfer/EntriesComparator.java

@@ -38,8 +38,9 @@ public class EntriesComparator {
    * @param jarFile1 Path to the first jar file.
    * @param jarFile2 Path to the second jar file.
    * @return True iff the entries present in the two jar files are the same.
-   * @throws IOException
+   * @throws IOException if an error happens when reading jar files.
    */
+  @SuppressWarnings("JdkObsolete")
   public static boolean compareEntriesInJars(String jarFile1, String jarFile2) throws IOException {
     Preconditions.checkArgument(jarFile1.endsWith(".jar"), "invalid jar file: " + jarFile1);
     Preconditions.checkArgument(jarFile2.endsWith(".jar"), "invalid jar file: " + jarFile2);
@@ -64,8 +65,9 @@ public static boolean compareEntriesInJars(String jarFile1, String jarFile2) thr
    * @param aarFile2 Path to the second aar file.
    * @return True iff the entries present in the two aar files are the same and entries in
    *     "classes.jar" in the two aar files are the same.
-   * @throws IOException
+   * @throws IOException if an error happens when reading aar files.
    */
+  @SuppressWarnings("JdkObsolete")
   public static boolean compareEntriesInAars(String aarFile1, String aarFile2) throws IOException {
     Preconditions.checkArgument(aarFile1.endsWith(".aar"), "invalid aar file: " + aarFile1);
     Preconditions.checkArgument(aarFile2.endsWith(".aar"), "invalid aar file: " + aarFile2);
@@ -132,8 +134,8 @@ private static String readManifestFromJar(String jarfile) throws IOException {
    * @param jarFile1 Path to the first jar file.
    * @param jarFile2 Path to the second jar file.
    * @return True iff the MANIFEST.MF files in the two jar files exist and are the same.
-   * @throws IOException
-   * @throws IllegalArgumentException
+   * @throws IOException if an error happens when reading jar files.
+   * @throws IllegalArgumentException if either jar does not contain a manifest.
    */
   public static boolean compareManifestContents(String jarFile1, String jarFile2)
       throws IOException {