Add --incompatible_strict_objc_module_maps.

This flag changes the behavior of objc_library module map propagation so that module maps are only propagated to direct dependents, not transitive dependents. swift_library targets that import Objective-C code must then list those dependencies directly in its deps instead of depending on them being transitively present.

PiperOrigin-RevId: 187184692

3 files changed, 31 insertions, 4 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java
index 64637c39d8..c836e345fe 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java
@@ -304,13 +304,26 @@ public class ObjcCommandLineOptions extends FragmentOptions {
     defaultValue = "null",
     converter = LabelConverter.class,
     documentationCategory = OptionDocumentationCategory.TOOLCHAIN,
-    effectTags = {OptionEffectTag.CHANGES_INPUTS, OptionEffectTag.LOADING_AND_ANALYSIS},
+    effectTags = {OptionEffectTag.AFFECTS_OUTPUTS, OptionEffectTag.LOADING_AND_ANALYSIS},
     help =
         "Location of target that will provide the appropriate Apple SDK for the current build "
             + "configuration."
   )
   public Label appleSdk;
 
+  @Option(
+    name = "incompatible_strict_objc_module_maps",
+    category = "incompatible changes",
+    defaultValue = "false",
+    documentationCategory = OptionDocumentationCategory.TOOLCHAIN,
+    metadataTags = {OptionMetadataTag.INCOMPATIBLE_CHANGE},
+    effectTags = {OptionEffectTag.CHANGES_INPUTS, OptionEffectTag.LOADING_AND_ANALYSIS},
+    help =
+        "Propagates Objective-C module maps only to direct dependencies in the 'objc' provider, "
+            + "not to all transitive dependencies."
+  )
+  public boolean strictObjcModuleMaps;
+
   @Override
   public FragmentOptions getHost() {
     ObjcCommandLineOptions host = (ObjcCommandLineOptions) super.getHost();
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
index 3019d7a1a3..fbfa23e121 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
@@ -545,8 +545,13 @@ public final class ObjcCommon {
         if (umbrellaHeader.isPresent()) {
           objcProvider.add(UMBRELLA_HEADER, umbrellaHeader.get());
         }
-        objcProvider.add(MODULE_MAP, moduleMap.getArtifact());
-        objcProvider.add(TOP_LEVEL_MODULE_MAP, moduleMap);
+        if (context.getFragment(ObjcConfiguration.class).useStrictObjcModuleMaps()) {
+          objcProvider.addForDirectDependents(MODULE_MAP, moduleMap.getArtifact());
+          objcProvider.addForDirectDependents(TOP_LEVEL_MODULE_MAP, moduleMap);
+        } else {
+          objcProvider.add(MODULE_MAP, moduleMap.getArtifact());
+          objcProvider.add(TOP_LEVEL_MODULE_MAP, moduleMap);
+        }
       }
 
       objcProvider
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcConfiguration.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcConfiguration.java
index 6139c2a541..d95e40ca7c 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcConfiguration.java
@@ -80,6 +80,7 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
   private final int objcHeaderThinningPartitionSize;
   private final Label objcHeaderScannerTool;
   private final Label appleSdk;
+  private final boolean strictObjcModuleMaps;
 
   ObjcConfiguration(ObjcCommandLineOptions objcOptions, BuildConfiguration.Options options) {
     this.iosSimulatorDevice =
@@ -115,6 +116,7 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
     this.objcHeaderThinningPartitionSize = objcOptions.objcHeaderThinningPartitionSize;
     this.objcHeaderScannerTool = objcOptions.objcHeaderScannerTool;
     this.appleSdk = objcOptions.appleSdk;
+    this.strictObjcModuleMaps = objcOptions.strictObjcModuleMaps;
   }
 
   @AutoCodec.Instantiator
@@ -142,7 +144,8 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
       boolean experimentalHeaderThinning,
       int objcHeaderThinningPartitionSize,
       Label objcHeaderScannerTool,
-      Label appleSdk) {
+      Label appleSdk,
+      boolean strictObjcModuleMaps) {
     this.iosSimulatorVersion = iosSimulatorVersion;
     this.iosSimulatorDevice = iosSimulatorDevice;
     this.watchosSimulatorVersion = watchosSimulatorVersion;
@@ -167,6 +170,7 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
     this.objcHeaderThinningPartitionSize = objcHeaderThinningPartitionSize;
     this.objcHeaderScannerTool = objcHeaderScannerTool;
     this.appleSdk = appleSdk;
+    this.strictObjcModuleMaps = strictObjcModuleMaps;
   }
 
   /**
@@ -375,4 +379,9 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
   public Label getAppleSdk() {
     return appleSdk;
   }
+
+  /** Returns true if Objective-C module maps should only be propagated to direct dependencies. */
+  public boolean useStrictObjcModuleMaps() {
+    return strictObjcModuleMaps;
+  }
 }