Support "probing" ignored tests; more Parcel impl.

As test authors onboard their bivalent tests, they'll be using the
`@IgnoreUnderRavenwood` annotation to quietly ignore tests that
don't currently have enough Ravenwood support to run.

However, over time the Ravenwood environment will continue to
gain new functionality, and we'd like an easy way to "probe" those
previously-ignored tests to see if any of them started passing.

This change implements this using a locally-configured flag
that unconditionally runs all tests under Ravenwood, and reports
failures for any tests marked as `@IgnoreUnderRavenwood` that
are now passing.  (As these "failures" might be confusing for normal
test authors, we leave it disabled by default in the build, and
leave it for internal Ravenwood maintainers.)

To confirm this works, implement two new methods on Parcel, and
detect the relevant tests that started passing.

Bug: 292141694
Test: atest CtsUtilTestCasesRavenwood CtsUtilTestCases
Change-Id: Ied2a5e3d1781c76a4f3506192d015309f2f424b2

1 files changed, 70 insertions, 9 deletions

diff --git a/ravenwood/junit-src/android/platform/test/ravenwood/RavenwoodRule.java b/ravenwood/junit-src/android/platform/test/ravenwood/RavenwoodRule.java
index d175713eb92f..513c09587026 100644
--- a/ravenwood/junit-src/android/platform/test/ravenwood/RavenwoodRule.java
+++ b/ravenwood/junit-src/android/platform/test/ravenwood/RavenwoodRule.java
@@ -16,6 +16,8 @@
 
 package android.platform.test.ravenwood;
 
+import static org.junit.Assert.fail;
+
 import android.platform.test.annotations.IgnoreUnderRavenwood;
 
 import org.junit.Assume;
@@ -36,6 +38,15 @@ public class RavenwoodRule implements TestRule {
 
     private static final boolean IS_UNDER_RAVENWOOD = RavenwoodRuleImpl.isUnderRavenwood();
 
+    /**
+     * When probing is enabled, all tests will be unconditionally run under Ravenwood to detect
+     * cases where a test is able to pass despite being marked as {@code IgnoreUnderRavenwood}.
+     *
+     * This is typically helpful for internal maintainers discovering tests that had previously
+     * been ignored, but now have enough Ravenwood-supported functionality to be enabled.
+     */
+    private static final boolean ENABLE_PROBE_IGNORED = false; // DO NOT SUBMIT WITH TRUE
+
     private static final int SYSTEM_UID = 1000;
     private static final int NOBODY_UID = 9999;
     private static final int FIRST_APPLICATION_UID = 10000;
@@ -97,26 +108,76 @@ public class RavenwoodRule implements TestRule {
         return IS_UNDER_RAVENWOOD;
     }
 
+    /**
+     * Test if the given {@link Description} has been marked with an {@link IgnoreUnderRavenwood}
+     * annotation, either at the method or class level.
+     */
+    private static boolean hasIgnoreUnderRavenwoodAnnotation(Description description) {
+        if (description.getTestClass().getAnnotation(IgnoreUnderRavenwood.class) != null) {
+            return true;
+        } else if (description.getAnnotation(IgnoreUnderRavenwood.class) != null) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+
     @Override
     public Statement apply(Statement base, Description description) {
+        if (ENABLE_PROBE_IGNORED) {
+            return applyProbeIgnored(base, description);
+        } else {
+            return applyDefault(base, description);
+        }
+    }
+
+    /**
+     * Run the given {@link Statement} with no special treatment.
+     */
+    private Statement applyDefault(Statement base, Description description) {
         return new Statement() {
             @Override
             public void evaluate() throws Throwable {
-                if (description.getTestClass().getAnnotation(IgnoreUnderRavenwood.class) != null) {
-                    Assume.assumeFalse(IS_UNDER_RAVENWOOD);
-                }
-                if (description.getAnnotation(IgnoreUnderRavenwood.class) != null) {
+                if (hasIgnoreUnderRavenwoodAnnotation(description)) {
                     Assume.assumeFalse(IS_UNDER_RAVENWOOD);
                 }
-                if (IS_UNDER_RAVENWOOD) {
-                    RavenwoodRuleImpl.init(RavenwoodRule.this);
-                }
+
+                RavenwoodRuleImpl.init(RavenwoodRule.this);
                 try {
                     base.evaluate();
                 } finally {
-                    if (IS_UNDER_RAVENWOOD) {
-                        RavenwoodRuleImpl.reset(RavenwoodRule.this);
+                    RavenwoodRuleImpl.reset(RavenwoodRule.this);
+                }
+            }
+        };
+    }
+
+    /**
+     * Run the given {@link Statement} with probing enabled. All tests will be unconditionally
+     * run under Ravenwood to detect cases where a test is able to pass despite being marked as
+     * {@code IgnoreUnderRavenwood}.
+     */
+    private Statement applyProbeIgnored(Statement base, Description description) {
+        return new Statement() {
+            @Override
+            public void evaluate() throws Throwable {
+                RavenwoodRuleImpl.init(RavenwoodRule.this);
+                try {
+                    base.evaluate();
+                } catch (Throwable t) {
+                    if (hasIgnoreUnderRavenwoodAnnotation(description)) {
+                        // This failure is expected, so eat the exception and report the
+                        // assumption failure that test authors expect
+                        Assume.assumeFalse(IS_UNDER_RAVENWOOD);
                     }
+                    throw t;
+                } finally {
+                    RavenwoodRuleImpl.reset(RavenwoodRule.this);
+                }
+
+                if (hasIgnoreUnderRavenwoodAnnotation(description) && IS_UNDER_RAVENWOOD) {
+                    fail("Test was annotated with IgnoreUnderRavenwood, but it actually "
+                            + "passed under Ravenwood; consider removing the annotation");
                 }
             }
         };