Rollback of commit 786cfa2ed980e278c42ee474408844f7e3720385.

*** Reason for rollback ***

Breaks dagger []: []

*** Original change description ***

Separate the classpaths of the TestRunner with the test target, and use a separate Classloader to load the test target's classes. This enables a clean separation of the classes of the TestRunner with the target under test.

This is achieved with the following steps:
1. Start the test runner with only the bare bones classpaths to the Test Runner's classes which are used by the system ClassLoader.
2. Have all the classpaths required to load the test target's classes in a TEST_TARGET_CLASSPATH envi...

***

--
PiperOrigin-RevId: 148405598
MOS_MIGRATED_REVID=148405598

6 files changed, 69 insertions, 141 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/java/BazelJavaSemantics.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/java/BazelJavaSemantics.java
index d988eb31ae..f5fa1ff7ae 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/java/BazelJavaSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/java/BazelJavaSemantics.java
@@ -24,6 +24,7 @@ import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.Runfiles;
+import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.analysis.actions.CustomCommandLine;
 import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction;
@@ -32,22 +33,18 @@ import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction.Su
 import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction.Template;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
 import com.google.devtools.build.lib.bazel.rules.BazelConfiguration;
-import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
-import com.google.devtools.build.lib.collect.nestedset.Order;
 import com.google.devtools.build.lib.packages.BuildType;
-import com.google.devtools.build.lib.packages.TargetUtils;
 import com.google.devtools.build.lib.rules.java.DeployArchiveBuilder;
 import com.google.devtools.build.lib.rules.java.DeployArchiveBuilder.Compression;
 import com.google.devtools.build.lib.rules.java.JavaCommon;
-import com.google.devtools.build.lib.rules.java.JavaCompilationArgs;
-import com.google.devtools.build.lib.rules.java.JavaCompilationArgs.ClasspathType;
 import com.google.devtools.build.lib.rules.java.JavaCompilationArgsProvider;
 import com.google.devtools.build.lib.rules.java.JavaCompilationArtifacts;
 import com.google.devtools.build.lib.rules.java.JavaCompilationHelper;
 import com.google.devtools.build.lib.rules.java.JavaConfiguration;
 import com.google.devtools.build.lib.rules.java.JavaHelper;
 import com.google.devtools.build.lib.rules.java.JavaRuleOutputJarsProvider;
+import com.google.devtools.build.lib.rules.java.JavaRunfilesProvider;
 import com.google.devtools.build.lib.rules.java.JavaSemantics;
 import com.google.devtools.build.lib.rules.java.JavaSourceJarsProvider;
 import com.google.devtools.build.lib.rules.java.JavaTargetAttributes;
@@ -84,8 +81,6 @@ public class BazelJavaSemantics implements JavaSemantics {
   private static final String JACOCO_COVERAGE_RUNNER_MAIN_CLASS =
       "com.google.testing.coverage.JacocoCoverageRunner";
 
-  private static final String BAZEL_TEST_RUNNER = "com.google.testing.junit.runner.BazelTestRunner";
-
   private BazelJavaSemantics() {
   }
 
@@ -108,20 +103,10 @@ public class BazelJavaSemantics implements JavaSemantics {
 
   private static final String JUNIT4_RUNNER = "org.junit.runner.JUnitCore";
 
-  @Nullable
   private String getMainClassInternal(RuleContext ruleContext, ImmutableList<Artifact> sources) {
     if (!ruleContext.attributes().get("create_executable", Type.BOOLEAN)) {
       return null;
     }
-    String mainClass = determineMainClassFromRule(ruleContext);
-
-    if (mainClass.isEmpty()) {
-      mainClass = JavaCommon.determinePrimaryClass(ruleContext, sources);
-    }
-    return mainClass;
-  }
-
-  private String determineMainClassFromRule(RuleContext ruleContext) {
     String mainClass = ruleContext.attributes().get("main_class", Type.STRING);
 
     // Legacy behavior for java_test rules: main_class defaulted to JUnit4 runner.
@@ -135,8 +120,9 @@ public class BazelJavaSemantics implements JavaSemantics {
     if (mainClass.isEmpty()) {
       if (ruleContext.attributes().get("use_testrunner", Type.BOOLEAN)
           && !useLegacyJavaTest(ruleContext)) {
-        return BAZEL_TEST_RUNNER;
+        return "com.google.testing.junit.runner.BazelTestRunner";
       }
+      mainClass = JavaCommon.determinePrimaryClass(ruleContext, sources);
     }
     return mainClass;
   }
@@ -178,55 +164,10 @@ public class BazelJavaSemantics implements JavaSemantics {
     return ruleContext.getPrerequisiteArtifacts("resources", Mode.TARGET).list();
   }
 
-  /**
-   * Used to generate the Classpaths contained within the stub.
-   */
-  private static class ComputedClasspathSubstitution extends ComputedSubstitution {
-    private final NestedSet<Artifact> jars;
-    private final String workspacePrefix;
-    private final boolean isRunfilesEnabled;
-
-    ComputedClasspathSubstitution(
-        String key, NestedSet<Artifact> jars, String workspacePrefix, boolean isRunfilesEnabled) {
-      super(key);
-      this.jars = jars;
-      this.workspacePrefix = workspacePrefix;
-      this.isRunfilesEnabled = isRunfilesEnabled;
-    }
-
-    /**
-     * Builds a class path by concatenating the root relative paths of the artifacts. Each relative
-     * path entry is prepended with "${RUNPATH}" which will be expanded by the stub script at
-     * runtime, to either "${JAVA_RUNFILES}/" or if we are lucky, the empty string.
-     */
-    @Override
-    public String getValue() {
-      StringBuilder buffer = new StringBuilder();
-      buffer.append("\"");
-      for (Artifact artifact : jars) {
-        if (buffer.length() > 1) {
-          buffer.append(File.pathSeparatorChar);
-        }
-        if (!isRunfilesEnabled) {
-          buffer.append("$(rlocation ");
-          PathFragment runfilePath =
-              new PathFragment(new PathFragment(workspacePrefix), artifact.getRunfilesPath());
-          buffer.append(runfilePath.normalize().getPathString());
-          buffer.append(")");
-        } else {
-          buffer.append("${RUNPATH}");
-          buffer.append(artifact.getRunfilesPath().getPathString());
-        }
-      }
-      buffer.append("\"");
-      return buffer.toString();
-    }
-  }
-
   @Override
   public Artifact createStubAction(
       RuleContext ruleContext,
-      JavaCommon javaCommon,
+      final JavaCommon javaCommon,
       List<String> jvmFlags,
       Artifact executable,
       String javaStartClass,
@@ -247,26 +188,18 @@ public class BazelJavaSemantics implements JavaSemantics {
     arguments.add(Substitution.of("%javabin%", javaExecutable));
     arguments.add(Substitution.of("%needs_runfiles%",
         ruleContext.getFragment(Jvm.class).getJavaExecutable().isAbsolute() ? "0" : "1"));
-
-    NestedSet<Artifact> classpath = javaCommon.getRuntimeClasspath();
-    NestedSet<Artifact> testTargetClasspath = NestedSetBuilder.emptySet(Order.STABLE_ORDER);
-    TransitiveInfoCollection testSupport = getTestSupport(ruleContext);
-    if (TargetUtils.isTestRule(ruleContext.getRule())
-        && determineMainClassFromRule(ruleContext).equals(BAZEL_TEST_RUNNER)
-        && testSupport != null) {
-      // Keep only the locations containing the classes to start the test runner itself within,
-      // classpath variable, and place all the paths required for the test run in
-      // testTargetClasspath, so that the classes for the test target may be loaded by a separate
-      // ClassLoader.
-      testTargetClasspath = classpath;
-      classpath = getRuntimeJarsForTargets(testSupport);
-    }
     arguments.add(
-        new ComputedClasspathSubstitution(
-            "%classpath%", classpath, workspacePrefix, isRunfilesEnabled));
-    arguments.add(
-        new ComputedClasspathSubstitution(
-            "%test_target_classpath%", testTargetClasspath, workspacePrefix, isRunfilesEnabled));
+        new ComputedSubstitution("%classpath%") {
+          @Override
+          public String getValue() {
+            StringBuilder buffer = new StringBuilder();
+            Iterable<Artifact> jars = javaCommon.getRuntimeClasspath();
+            char delimiter = File.pathSeparatorChar;
+            appendRunfilesRelativeEntries(
+                buffer, jars, workspacePrefix, delimiter, isRunfilesEnabled);
+            return buffer.toString();
+          }
+        });
 
     JavaCompilationArtifacts javaArtifacts = javaCommon.getJavaCompilationArtifacts();
     String path =
@@ -317,7 +250,40 @@ public class BazelJavaSemantics implements JavaSemantics {
     }
   }
 
-  @Nullable
+  /**
+   * Builds a class path by concatenating the root relative paths of the artifacts separated by the
+   * delimiter. Each relative path entry is prepended with "${RUNPATH}" which will be expanded by
+   * the stub script at runtime, to either "${JAVA_RUNFILES}/" or if we are lucky, the empty string.
+   *
+   * @param buffer the buffer to use for concatenating the entries
+   * @param artifacts the entries to concatenate in the buffer
+   * @param delimiter the delimiter character to separate the entries
+   */
+  private static void appendRunfilesRelativeEntries(
+      StringBuilder buffer,
+      Iterable<Artifact> artifacts,
+      String workspacePrefix,
+      char delimiter,
+      boolean isRunfilesEnabled) {
+    buffer.append("\"");
+    for (Artifact artifact : artifacts) {
+      if (buffer.length() > 1) {
+        buffer.append(delimiter);
+      }
+      if (!isRunfilesEnabled) {
+        buffer.append("$(rlocation ");
+        PathFragment runfilePath =
+            new PathFragment(new PathFragment(workspacePrefix), artifact.getRunfilesPath());
+        buffer.append(runfilePath.normalize().getPathString());
+        buffer.append(")");
+      } else {
+        buffer.append("${RUNPATH}");
+        buffer.append(artifact.getRunfilesPath().getPathString());
+      }
+    }
+    buffer.append("\"");
+  }
+
   private TransitiveInfoCollection getTestSupport(RuleContext ruleContext) {
     if (!isJavaBinaryOrJavaTest(ruleContext)) {
       return null;
@@ -334,25 +300,13 @@ public class BazelJavaSemantics implements JavaSemantics {
     }
   }
 
-  private static NestedSet<Artifact> getRuntimeJarsForTargets(TransitiveInfoCollection... deps) {
-    // The dep may be a simple JAR and not a java rule, hence we can't simply do
-    // dep.getProvider(JavaCompilationArgsProvider.class).getRecursiveJavaCompilationArgs(),
-    // so we reuse the logic within JavaCompilationArgs to handle both scenarios.
-    JavaCompilationArgs args =
-        JavaCompilationArgs.builder()
-            .addTransitiveTargets(
-                ImmutableList.copyOf(deps), /*recursive=*/ true, ClasspathType.RUNTIME_ONLY)
-            .build();
-    return args.getRuntimeJars();
-  }
-
   @Override
   public void addRunfilesForBinary(RuleContext ruleContext, Artifact launcher,
       Runfiles.Builder runfilesBuilder) {
     TransitiveInfoCollection testSupport = getTestSupport(ruleContext);
     if (testSupport != null) {
-      // Not using addTransitiveArtifacts() due to the mismatch in NestedSet ordering.
-      runfilesBuilder.addArtifacts(getRuntimeJarsForTargets(testSupport));
+      runfilesBuilder.addTarget(testSupport, JavaRunfilesProvider.TO_RUNFILES);
+      runfilesBuilder.addTarget(testSupport, RunfilesProvider.DEFAULT_RUNFILES);
     }
   }
 
@@ -362,16 +316,12 @@ public class BazelJavaSemantics implements JavaSemantics {
 
   @Override
   public void collectTargetsTreatedAsDeps(
-      RuleContext ruleContext,
-      ImmutableList.Builder<TransitiveInfoCollection> builder,
-      ClasspathType type) {
-    if (type == ClasspathType.COMPILE_ONLY) {
-      // We add the test support below, but the test framework's deps are not relevant for
-      // COMPILE_ONLY, hence we return here.
-      return;
-    }
+      RuleContext ruleContext, ImmutableList.Builder<TransitiveInfoCollection> builder) {
     TransitiveInfoCollection testSupport = getTestSupport(ruleContext);
     if (testSupport != null) {
+      // TODO(bazel-team): The testsupport is used as the test framework
+      // and really only needs to be on the runtime, not compile-time
+      // classpath.
       builder.add(testSupport);
     }
   }
diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/java/java_stub_template.txt b/src/main/java/com/google/devtools/build/lib/bazel/rules/java/java_stub_template.txt
index 312976f586..cdc7ee4aa7 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/java/java_stub_template.txt
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/java/java_stub_template.txt
@@ -228,10 +228,6 @@ else
   CLASSPATH=%classpath%
 fi
 
-# Export the classpaths which would be used to load the classes of the test target as an
-# environment variable.
-export TEST_TARGET_CLASSPATH=%test_target_classpath%
-
 # If using Jacoco in offline instrumentation mode, the CLASSPATH contains instrumented files.
 # We need to make the metadata jar with uninstrumented classes available for generating
 # the lcov-compatible coverage report, and we don't want it on the classpath.
diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaBinary.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaBinary.java
index 8056e7cb0d..03c6a594a3 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaBinary.java
@@ -95,6 +95,10 @@ public class JavaBinary implements RuleConfiguredTargetFactory {
       }
     }
 
+    List<TransitiveInfoCollection> deps =
+        // Do not remove <TransitiveInfoCollection>: workaround for Java 7 type inference.
+        Lists.<TransitiveInfoCollection>newArrayList(
+            common.targetsTreatedAsDeps(ClasspathType.COMPILE_ONLY));
     semantics.checkRule(ruleContext, common);
     semantics.checkForProtoLibraryAndJavaProtoLibraryOnSameProto(ruleContext, common);
     String mainClass = semantics.getMainClass(ruleContext, common.getSrcsArtifacts());
@@ -106,10 +110,6 @@ public class JavaBinary implements RuleConfiguredTargetFactory {
     // Collect the transitive dependencies.
     JavaCompilationHelper helper = new JavaCompilationHelper(
         ruleContext, semantics, common.getJavacOpts(), attributesBuilder);
-    List<TransitiveInfoCollection> deps =
-        // Do not remove <TransitiveInfoCollection>: workaround for Java 7 type inference.
-        Lists.<TransitiveInfoCollection>newArrayList(
-            common.targetsTreatedAsDeps(ClasspathType.COMPILE_ONLY));
     helper.addLibrariesToAttributes(deps);
     attributesBuilder.addNativeLibraries(
         collectNativeLibraries(common.targetsTreatedAsDeps(ClasspathType.BOTH)));
diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaCommon.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaCommon.java
index b6f0f2b448..344793423e 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaCommon.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaCommon.java
@@ -664,7 +664,7 @@ public class JavaCommon {
     }
     builder.addAll(ruleContext.getPrerequisites("deps", Mode.TARGET));
 
-    semantics.collectTargetsTreatedAsDeps(ruleContext, builder, type);
+    semantics.collectTargetsTreatedAsDeps(ruleContext, builder);
 
     // Implicitly add dependency on java launcher cc_binary when --java_launcher= is enabled,
     // or when launcher attribute is specified in a build rule.
diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaSemantics.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaSemantics.java
index 9f5034c1dc..ed638b2147 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaSemantics.java
@@ -37,7 +37,6 @@ import com.google.devtools.build.lib.packages.AttributeMap;
 import com.google.devtools.build.lib.packages.ImplicitOutputsFunction.SafeImplicitOutputsFunction;
 import com.google.devtools.build.lib.packages.Rule;
 import com.google.devtools.build.lib.rules.java.DeployArchiveBuilder.Compression;
-import com.google.devtools.build.lib.rules.java.JavaCompilationArgs.ClasspathType;
 import com.google.devtools.build.lib.rules.java.proto.GeneratedExtensionRegistryProvider;
 import com.google.devtools.build.lib.util.FileType;
 import com.google.devtools.build.lib.vfs.PathFragment;
@@ -263,7 +262,7 @@ public interface JavaSemantics {
    */
   Artifact createStubAction(
       RuleContext ruleContext,
-      JavaCommon javaCommon,
+      final JavaCommon javaCommon,
       List<String> jvmFlags,
       Artifact executable,
       String javaStartClass,
@@ -285,11 +284,11 @@ public interface JavaSemantics {
    */
   Iterable<String> getExtraJavacOpts(RuleContext ruleContext);
 
-  /** Add additional targets to be treated as direct dependencies. */
+  /**
+   * Add additional targets to be treated as direct dependencies.
+   */
   void collectTargetsTreatedAsDeps(
-      RuleContext ruleContext,
-      ImmutableList.Builder<TransitiveInfoCollection> builder,
-      ClasspathType type);
+      RuleContext ruleContext, ImmutableList.Builder<TransitiveInfoCollection> builder);
 
   /**
    * Enables coverage support for the java target - adds instrumented jar to the classpath and
diff --git a/src/main/java/com/google/devtools/build/lib/worker/WorkerTestStrategy.java b/src/main/java/com/google/devtools/build/lib/worker/WorkerTestStrategy.java
index e4193e8420..d4a0fa8140 100644
--- a/src/main/java/com/google/devtools/build/lib/worker/WorkerTestStrategy.java
+++ b/src/main/java/com/google/devtools/build/lib/worker/WorkerTestStrategy.java
@@ -92,7 +92,7 @@ public class WorkerTestStrategy extends StandaloneTestStrategy {
     return execInWorker(
         action,
         actionExecutionContext,
-        addPersistentRunnerVars(spawn.getEnvironment()),
+        spawn.getEnvironment(),
         startupArgs,
         actionExecutionContext.getExecutor().getExecRoot(),
         maxRetries);
@@ -107,12 +107,6 @@ public class WorkerTestStrategy extends StandaloneTestStrategy {
       int retriesLeft)
       throws ExecException, InterruptedException, IOException {
     Executor executor = actionExecutionContext.getExecutor();
-    // TODO(kush): Remove once we're out of the experimental phase.
-    executor
-        .getEventHandler()
-        .handle(
-            Event.warn(
-                "RUNNING TEST IN AN EXPERIMENTAL PERSISTENT WORKER. RESULTS MAY BE INACCURATE"));
     TestResultData.Builder builder = TestResultData.newBuilder();
 
     Path testLogPath = action.getTestLog().getPath();
@@ -197,19 +191,6 @@ public class WorkerTestStrategy extends StandaloneTestStrategy {
     }
   }
 
-  private static Map<String, String> addPersistentRunnerVars(Map<String, String> originalEnv)
-      throws UserExecException {
-    if (originalEnv.containsKey("PERSISTENT_TEST_RUNNER")) {
-      throw new UserExecException(
-          "Found clashing environment variable with persistent_test_runner."
-              + " Please use another test strategy");
-    }
-    return ImmutableMap.<String, String>builder()
-        .putAll(originalEnv)
-        .put("PERSISTENT_TEST_RUNNER", "true")
-        .build();
-  }
-
   private List<String> getStartUpArgs(TestRunnerAction action) throws ExecException {
     List<String> args = getArgs(/*coverageScript=*/ "", action);
     ImmutableList.Builder<String> startupArgs = ImmutableList.builder();
@@ -217,6 +198,8 @@ public class WorkerTestStrategy extends StandaloneTestStrategy {
     startupArgs.add(args.get(0)).add("--no_echo");
     // Add remaining of the original args.
     startupArgs.addAll(args.subList(1, args.size()));
+    // Make the Test runner run persistently.
+    startupArgs.add("--persistent_test_runner");
     // Add additional flags requested for this invocation.
     startupArgs.addAll(MoreObjects.firstNonNull(
             extraFlags.get(action.getMnemonic()), ImmutableList.<String>of()));