Add support for Rex package map

--
MOS_MIGRATED_REVID=137877037

2 files changed, 32 insertions, 1 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java
index af68930c66..9a40b22f97 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java
@@ -151,6 +151,21 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
           "'proguard_apply_mapping' can only be used when 'proguard_specs' is also set");
     }
 
+    if (ruleContext.attributes().isAttributeValueExplicitlySpecified("rex_package_map")
+        && !ruleContext.attributes().get("rewrite_dexes_with_rex", Type.BOOLEAN)) {
+      ruleContext.throwWithAttributeError(
+          "rex_package_map",
+          "'rex_package_map' can only be used when 'rewrite_dexes_with_rex' is also set");
+    }
+
+    if (ruleContext.attributes().isAttributeValueExplicitlySpecified("rex_package_map")
+        && ruleContext.attributes()
+        .get(ProguardHelper.PROGUARD_SPECS, BuildType.LABEL_LIST)
+        .isEmpty()) {
+      ruleContext.throwWithAttributeError("rex_package_map",
+          "'rex_package_map' can only be used when 'proguard_specs' is also set");
+    }
+
     // TODO(bazel-team): Find a way to simplify this code.
     // treeKeys() means that the resulting map sorts the entries by key, which is necessary to
     // ensure determinism.
@@ -462,11 +477,19 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
           .addOutputArgument(finalDexes);
       if (proguardOutput.getMapping() != null) {
         finalProguardMap = getDxArtifact(ruleContext, "rexed_proguard.map");
+        Artifact finalRexPackageMap = getDxArtifact(ruleContext, "rex_output_package.map");
         rexActionBuilder
             .addArgument("--proguard_input_map")
             .addInputArgument(proguardOutput.getMapping())
             .addArgument("--proguard_output_map")
-            .addOutputArgument(finalProguardMap);
+            .addOutputArgument(finalProguardMap)
+            .addArgument("--rex_output_package_map")
+            .addOutputArgument(finalRexPackageMap);
+        if (ruleContext.attributes().isAttributeValueExplicitlySpecified("rex_package_map")) {
+          Artifact rexPackageMap =
+              ruleContext.getPrerequisiteArtifact("rex_package_map", Mode.TARGET);
+          rexActionBuilder.addArgument("--rex_input_package_map").addInputArgument(rexPackageMap);
+        }
       } else {
         finalProguardMap = proguardOutput.getMapping();
       }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidRuleClasses.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidRuleClasses.java
index 0efb3dc191..e1156fa866 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidRuleClasses.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidRuleClasses.java
@@ -783,6 +783,14 @@ public final class AndroidRuleClasses {
                   .undocumented("No-op, soon to be removed"))
           .add(attr(":extra_proguard_specs", LABEL_LIST).value(JavaSemantics.EXTRA_PROGUARD_SPECS))
           .add(attr("rewrite_dexes_with_rex", BOOLEAN).value(false).undocumented("experimental"))
+          /*
+          File to be used as a package map for Rex tool that keeps the assignment of classes to
+          dex files of a multi-dex application stable over time.
+          Can only be used when <code>proguard_specs</code> is also specified. When
+          <code>proguard_specs</code> is specified, but a package map isn't or there were changes,
+          Rex suggests an updated package map that can be saved and reused for subsequent builds.
+           */
+          .add(attr("rex_package_map", LABEL).legacyAllowAnyFileType().undocumented("experimental"))
           .advertiseProvider(JavaCompilationArgsProvider.class)
           .build();
       }