Remove redundant preconditions from generated ProGuard rules (#1913)

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

@@ -26,7 +26,8 @@ import com.squareup.kotlinpoet.ClassName
  *   constructor as well as the DefaultConstructorMarker type Kotlin adds to it.
  *
  * Each rule is intended to be as specific and targeted as possible to reduce footprint, and each is
- * conditioned on usage of the original target type.
+ * conditioned on usage of the original target type (implicitly for keepnames and keepclassmembers,
+ * which have no effect if the target type was removed in the shrinking phase).
  *
  * To keep this processor as an ISOLATING incremental processor, we generate one file per target
  * class with a deterministic name (see [outputFilePathWithoutExtension]) with an appropriate
@@ -46,7 +47,6 @@ public data class ProguardConfig(
 
   public fun writeTo(out: Appendable): Unit = out.run {
     //
-    // -if class {the target class}
     // -keepnames class {the target class}
     // -if class {the target class}
     // -keep class {the generated adapter} {
@@ -57,7 +57,6 @@ public data class ProguardConfig(
     val targetName = targetClass.reflectionName()
     val adapterCanonicalName = ClassName(targetClass.packageName, adapterName).canonicalName
     // Keep the class name for Moshi's reflective lookup based on it
-    appendLine("-if class $targetName")
     appendLine("-keepnames class $targetName")
 
     appendLine("-if class $targetName")
@@ -70,6 +69,7 @@ public data class ProguardConfig(
     if (targetConstructorHasDefaults) {
       // If the target class has default parameter values, keep its synthetic constructor
       //
+      // -if class {the target class}
       // -keepnames class kotlin.jvm.internal.DefaultConstructorMarker
       // -keepclassmembers @com.squareup.moshi.JsonClass @kotlin.Metadata class * {
       //     synthetic <init>(...);
@@ -77,7 +77,6 @@ public data class ProguardConfig(
       //
       appendLine("-if class $targetName")
       appendLine("-keepnames class kotlin.jvm.internal.DefaultConstructorMarker")
-      appendLine("-if class $targetName")
       appendLine("-keepclassmembers class $targetName {")
       val allParams = targetConstructorParams.toMutableList()
       val maskCount = if (targetConstructorParams.isEmpty()) {

moshi-kotlin-codegen/src/test/java/com/squareup/moshi/kotlin/codegen/ksp/JsonClassSymbolProcessorTest.kt

@@ -727,7 +727,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
       when (generatedFile.nameWithoutExtension) {
         "moshi-testPackage.Aliases" -> assertThat(generatedFile.readText()).contains(
           """
-          -if class testPackage.Aliases
           -keepnames class testPackage.Aliases
           -if class testPackage.Aliases
           -keep class testPackage.AliasesJsonAdapter {
@@ -738,7 +737,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
 
         "moshi-testPackage.Simple" -> assertThat(generatedFile.readText()).contains(
           """
-          -if class testPackage.Simple
           -keepnames class testPackage.Simple
           -if class testPackage.Simple
           -keep class testPackage.SimpleJsonAdapter {
@@ -749,7 +747,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
 
         "moshi-testPackage.Generic" -> assertThat(generatedFile.readText()).contains(
           """
-          -if class testPackage.Generic
           -keepnames class testPackage.Generic
           -if class testPackage.Generic
           -keep class testPackage.GenericJsonAdapter {
@@ -761,7 +758,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
         "moshi-testPackage.UsingQualifiers" -> {
           assertThat(generatedFile.readText()).contains(
             """
-            -if class testPackage.UsingQualifiers
             -keepnames class testPackage.UsingQualifiers
             -if class testPackage.UsingQualifiers
             -keep class testPackage.UsingQualifiersJsonAdapter {
@@ -773,7 +769,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
 
         "moshi-testPackage.MixedTypes" -> assertThat(generatedFile.readText()).contains(
           """
-          -if class testPackage.MixedTypes
           -keepnames class testPackage.MixedTypes
           -if class testPackage.MixedTypes
           -keep class testPackage.MixedTypesJsonAdapter {
@@ -784,7 +779,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
 
         "moshi-testPackage.DefaultParams" -> assertThat(generatedFile.readText()).contains(
           """
-          -if class testPackage.DefaultParams
           -keepnames class testPackage.DefaultParams
           -if class testPackage.DefaultParams
           -keep class testPackage.DefaultParamsJsonAdapter {
@@ -792,7 +786,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
           }
           -if class testPackage.DefaultParams
           -keepnames class kotlin.jvm.internal.DefaultConstructorMarker
-          -if class testPackage.DefaultParams
           -keepclassmembers class testPackage.DefaultParams {
               public synthetic <init>(java.lang.String,int,kotlin.jvm.internal.DefaultConstructorMarker);
           }
@@ -802,7 +795,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
         "moshi-testPackage.Complex" -> {
           assertThat(generatedFile.readText()).contains(
             """
-            -if class testPackage.Complex
             -keepnames class testPackage.Complex
             -if class testPackage.Complex
             -keep class testPackage.ComplexJsonAdapter {
@@ -810,7 +802,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
             }
             -if class testPackage.Complex
             -keepnames class kotlin.jvm.internal.DefaultConstructorMarker
-            -if class testPackage.Complex
             -keepclassmembers class testPackage.Complex {
                 public synthetic <init>(java.lang.String,java.util.List,java.lang.Object,int,kotlin.jvm.internal.DefaultConstructorMarker);
             }
@@ -820,7 +811,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
 
         "moshi-testPackage.MultipleMasks" -> assertThat(generatedFile.readText()).contains(
           """
-          -if class testPackage.MultipleMasks
           -keepnames class testPackage.MultipleMasks
           -if class testPackage.MultipleMasks
           -keep class testPackage.MultipleMasksJsonAdapter {
@@ -828,7 +818,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
           }
           -if class testPackage.MultipleMasks
           -keepnames class kotlin.jvm.internal.DefaultConstructorMarker
-          -if class testPackage.MultipleMasks
           -keepclassmembers class testPackage.MultipleMasks {
               public synthetic <init>(long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,long,int,int,int,kotlin.jvm.internal.DefaultConstructorMarker);
           }
@@ -838,7 +827,6 @@ class JsonClassSymbolProcessorTest(private val useKSP2: Boolean) {
         "moshi-testPackage.NestedType.NestedSimple" -> {
           assertThat(generatedFile.readText()).contains(
             """
-            -if class testPackage.NestedType${'$'}NestedSimple
             -keepnames class testPackage.NestedType${'$'}NestedSimple
             -if class testPackage.NestedType${'$'}NestedSimple
             -keep class testPackage.NestedType_NestedSimpleJsonAdapter {