Add an argument to be disable proguard code generating (#1353)

Co-authored-by: SeongUg Jung <seongug.jung@hanwha.com>
Co-authored-by: Zac Sweers <pandanomic@gmail.com>

kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/JsonClassCodegenProcessor.kt

@@ -59,6 +59,13 @@ public class JsonClassCodegenProcessor : AbstractProcessor() {
      *   * `"javax.annotation.Generated"` (JRE <9)
      */
     public const val OPTION_GENERATED: String = "moshi.generated"
+
+    /**
+     * This annotation processing argument disables proguard rule generation.
+     * Normally, this is not recommended unless end-users build their own JsonAdapter look-up tool.
+     * This is enabled by default
+     */
+    public const val OPTION_ENABLE_PROGUARD_RULE_GENERATION: String = "moshi.enabledProguardGenerated"
     private val POSSIBLE_GENERATED_NAMES = arrayOf(
       ClassName("javax.annotation.processing", "Generated"),
       ClassName("javax.annotation", "Generated")
@@ -72,6 +79,7 @@ public class JsonClassCodegenProcessor : AbstractProcessor() {
   private lateinit var cachedClassInspector: MoshiCachedClassInspector
   private val annotation = JsonClass::class.java
   private var generatedType: ClassName? = null
+  private var generateProguardRules: Boolean = true
 
   override fun getSupportedAnnotationTypes(): Set<String> = setOf(annotation.canonicalName)
 
@@ -87,6 +95,9 @@ public class JsonClassCodegenProcessor : AbstractProcessor() {
           "allowable values are $POSSIBLE_GENERATED_NAMES."
       )
     }
+
+    generateProguardRules = processingEnv.options[OPTION_ENABLE_PROGUARD_RULE_GENERATION]?.toBooleanStrictOrNull() ?: true
+
     this.types = processingEnv.typeUtils
     this.elements = processingEnv.elementUtils
     this.filer = processingEnv.filer
@@ -113,7 +124,7 @@ public class JsonClassCodegenProcessor : AbstractProcessor() {
       if (jsonClass.generateAdapter && jsonClass.generator.isEmpty()) {
         val generator = adapterGenerator(type, cachedClassInspector) ?: continue
         val preparedAdapter = generator
-          .prepare { spec ->
+          .prepare(generateProguardRules) { spec ->
             spec.toBuilder()
               .apply {
                 @Suppress("DEPRECATION") // This is a Java type
@@ -134,7 +145,9 @@ public class JsonClassCodegenProcessor : AbstractProcessor() {
           }
 
         preparedAdapter.spec.writeTo(filer)
-        preparedAdapter.proguardConfig?.writeTo(filer, type)
+        if (generateProguardRules) {
+          preparedAdapter.proguardConfig?.writeTo(filer, type)
+        }
       }
     }
 

kotlin/codegen/src/main/java/com/squareup/moshi/kotlin/codegen/api/AdapterGenerator.kt

@@ -163,7 +163,7 @@ internal class AdapterGenerator(
     .initializer("null")
     .build()
 
-  fun prepare(typeHook: (TypeSpec) -> TypeSpec = { it }): PreparedAdapter {
+  fun prepare(generatedProguard: Boolean, typeHook: (TypeSpec) -> TypeSpec = { it }): PreparedAdapter {
     val reservedSimpleNames = mutableSetOf<String>()
     for (property in nonTransientProperties) {
       // Allocate names for simple property types first to avoid collisions
@@ -181,7 +181,12 @@ internal class AdapterGenerator(
     result.addComment("Code generated by moshi-kotlin-codegen. Do not edit.")
     result.addAnnotation(COMMON_SUPPRESS)
     result.addType(generatedAdapter)
-    return PreparedAdapter(result.build(), generatedAdapter.createProguardRule())
+    val proguardConfig = if (generatedProguard) {
+      generatedAdapter.createProguardRule()
+    } else {
+      null
+    }
+    return PreparedAdapter(result.build(), proguardConfig)
   }
 
   private fun TypeSpec.createProguardRule(): ProguardConfig {

kotlin/codegen/src/test/java/com/squareup/moshi/kotlin/codegen/JsonClassCodegenProcessorTest.kt

@@ -355,6 +355,23 @@ class JsonClassCodegenProcessorTest {
       "Invalid option value for ${JsonClassCodegenProcessor.OPTION_GENERATED}"
     )
   }
+  @Test
+  fun disableProguardRulesGenerating() {
+    val result = prepareCompilation(
+      kotlin(
+        "source.kt",
+        """
+          import com.squareup.moshi.JsonClass
+
+          @JsonClass(generateAdapter = true)
+          data class Foo(val a: Int)
+          """
+      )
+    ).apply {
+      kaptArgs[JsonClassCodegenProcessor.OPTION_ENABLE_PROGUARD_RULE_GENERATION] = "false"
+    }.compile()
+    assertThat(result.generatedFiles.filter { it.endsWith(".pro") }).isEmpty()
+  }
 
   @Test
   fun multipleErrors() {