From a580992dc4e28b7a196a37dda0b542159246c396 Mon Sep 17 00:00:00 2001
From: Stefan Haustein <haustein@google.com>
Date: Wed, 17 Dec 2025 08:50:31 -0800
Subject: [PATCH] Add Kotlin "@ObjcEnum"-compatible aliases for J2ObjC enum
 constants.

PiperOrigin-RevId: 845787437
---
 .../j2objc/gen/TypeDeclarationGenerator.java     | 11 +++++++++++
 .../google/devtools/j2objc/util/NameTable.java   | 16 ++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/translator/src/main/java/com/google/devtools/j2objc/gen/TypeDeclarationGenerator.java b/translator/src/main/java/com/google/devtools/j2objc/gen/TypeDeclarationGenerator.java
index 2106b7f540..f0855d028a 100644
--- a/translator/src/main/java/com/google/devtools/j2objc/gen/TypeDeclarationGenerator.java
+++ b/translator/src/main/java/com/google/devtools/j2objc/gen/TypeDeclarationGenerator.java
@@ -215,6 +215,17 @@ private void printNativeEnum() {
       }
       print("\n");
 
+      // Provide aliases for compatibility with kotlin
+      for (EnumConstantDeclaration constant : constants) {
+        String nativeConstantName = nameTable.getNativeEnumConstantName(typeElement, constant);
+        String kotlinConstantName =
+            nameTable.getNativeKotlinEnumConstantName(typeElement, constant);
+        if (!nativeConstantName.equals(kotlinConstantName)) {
+          printf("#define %s %s\n", kotlinConstantName, nativeConstantName);
+        }
+      }
+      print("\n");
+
       // Use different types for transpiled Java ordinals (which expects ordinals to be int32_t) and
       // native code using the enum (where stricter ordinal types help clang warnings).
       printf(
diff --git a/translator/src/main/java/com/google/devtools/j2objc/util/NameTable.java b/translator/src/main/java/com/google/devtools/j2objc/util/NameTable.java
index 348250f8ed..d6c03b1647 100644
--- a/translator/src/main/java/com/google/devtools/j2objc/util/NameTable.java
+++ b/translator/src/main/java/com/google/devtools/j2objc/util/NameTable.java
@@ -1056,6 +1056,22 @@ public String getNativeEnumConstantName(
     }
   }
 
+  public String getNativeKotlinEnumConstantName(
+      TypeElement enumTypeElement, EnumConstantDeclaration constantDeclaration) {
+    return getNativeKotlinEnumConstantName(
+        enumTypeElement, constantDeclaration.getVariableElement());
+  }
+
+  public String getNativeKotlinEnumConstantName(
+      TypeElement enumTypeElement, VariableElement constantVariableElement) {
+    // Note that we stick to J2objc type name conventions here, avoiding type name churn in
+    // addition to the literal name change.
+    String enumBaseName = getFullName(enumTypeElement) + "_Enum";
+    String constantSuffix = getVariableBaseName(constantVariableElement);
+    constantSuffix = camelCaseName(constantSuffix, true);
+    return enumBaseName + constantSuffix;
+  }
+
   public String getNativeEnumSwiftConstantName(EnumConstantDeclaration constantDeclaration) {
     return camelCaseName(getVariableBaseName(constantDeclaration.getVariableElement()), false);
   }