Fix binary compatibility for inlined local delegated properies

 #KT-54650 Fixed

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/LocalDeclarationsLowering.kt

@@ -8,13 +8,14 @@ package org.jetbrains.kotlin.backend.common.lower
 import org.jetbrains.kotlin.backend.common.BodyLoweringPass
 import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.backend.common.descriptors.synthesizedString
-import org.jetbrains.kotlin.backend.common.ir.*
 import org.jetbrains.kotlin.backend.common.lower.inline.isInlineParameter
 import org.jetbrains.kotlin.backend.common.runOnFilePostfix
 import org.jetbrains.kotlin.descriptors.DescriptorVisibilities
 import org.jetbrains.kotlin.descriptors.DescriptorVisibility
 import org.jetbrains.kotlin.descriptors.Modality
-import org.jetbrains.kotlin.ir.*
+import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.IrStatement
+import org.jetbrains.kotlin.ir.UNDEFINED_OFFSET
 import org.jetbrains.kotlin.ir.builders.declarations.buildConstructor
 import org.jetbrains.kotlin.ir.builders.declarations.buildFun
 import org.jetbrains.kotlin.ir.builders.declarations.buildValueParameter
@@ -25,7 +26,9 @@ import org.jetbrains.kotlin.ir.symbols.IrFieldSymbol
 import org.jetbrains.kotlin.ir.symbols.IrValueParameterSymbol
 import org.jetbrains.kotlin.ir.symbols.IrValueSymbol
 import org.jetbrains.kotlin.ir.symbols.impl.IrFieldSymbolImpl
-import org.jetbrains.kotlin.ir.types.*
+import org.jetbrains.kotlin.ir.transformStatement
+import org.jetbrains.kotlin.ir.types.IrType
+import org.jetbrains.kotlin.ir.types.defaultType
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
@@ -71,6 +74,7 @@ class LocalDeclarationsLowering(
     val localNameSanitizer: (String) -> String = { it },
     val visibilityPolicy: VisibilityPolicy = VisibilityPolicy.DEFAULT,
     val suggestUniqueNames: Boolean = true, // When `true` appends a `$#index` suffix to lifted declaration names
+    val compatibilityModeForInlinedLocalDelegatedPropertyAccessors: Boolean = false, // Keep old names because of KT-49030
     val forceFieldsForInlineCaptures: Boolean = false, // See `LocalClassContext`
     private val postLocalDeclarationLoweringCallback: ((IntermediateDatastructures) -> Unit)? = null
 ) :
@@ -589,8 +593,16 @@ class LocalDeclarationsLowering(
             val declarationName = localNameSanitizer(declaration.name.asString())
             localFunctions[declaration]?.let {
                 val baseName = if (declaration.name.isSpecial) "lambda" else declarationName
-                if (it.index >= 0)
-                    return if (suggestUniqueNames) "$baseName\$${it.index}" else baseName
+                if (it.index >= 0) {
+                    if (!suggestUniqueNames) return baseName
+
+                    val separator = if (
+                        compatibilityModeForInlinedLocalDelegatedPropertyAccessors &&
+                        declaration.origin == IrDeclarationOrigin.DELEGATED_PROPERTY_ACCESSOR &&
+                        container is IrFunction && container.isInline
+                    ) "-" else "$"
+                    return "$baseName$separator${it.index}"
+                }
             }
 
             return declarationName

compiler/ir/backend.jvm/lower/src/org/jetbrains/kotlin/backend/jvm/JvmLower.kt

@@ -138,6 +138,7 @@ internal val localDeclarationsPhase = makeIrFilePhase(
                 private fun scopedVisibility(inInlineFunctionScope: Boolean): DescriptorVisibility =
                     if (inInlineFunctionScope) DescriptorVisibilities.PUBLIC else JavaDescriptorVisibilities.PACKAGE_VISIBILITY
             },
+            compatibilityModeForInlinedLocalDelegatedPropertyAccessors = true,
             forceFieldsForInlineCaptures = true,
             postLocalDeclarationLoweringCallback = context.localDeclarationsLoweringData?.let {
                 { data ->

compiler/testData/codegen/bytecodeListing/delegatedProperty/localDelegatedProperty.kt

@@ -0,0 +1,10 @@
+// This test checks that we use the `...$lambda-0` method name, instead of `...$lambda$0`, for extracted accessors of local delegated properties.
+// It's important to keep these names until we fix the binary compatibility issue KT-49030.
+
+operator fun String.getValue(thisRef: Any?, prop: Any?): String = this
+operator fun String.setValue(thisRef: Any?, prop: Any?, value: String) {}
+
+inline fun foo(): String {
+    var x by "OK"
+    return x
+}

compiler/testData/codegen/bytecodeListing/delegatedProperty/localDelegatedProperty.txt

@@ -0,0 +1,20 @@
+@kotlin.Metadata
+public final class LocalDelegatedPropertyKt$foo$x$1 {
+    // source: 'localDelegatedProperty.kt'
+    public final static field INSTANCE: kotlin.reflect.KMutableProperty0
+    static method <clinit>(): void
+    method <init>(): void
+    public method getName(): java.lang.String
+    public method getOwner(): kotlin.reflect.KDeclarationContainer
+    public method getSignature(): java.lang.String
+}
+
+@kotlin.Metadata
+public final class LocalDelegatedPropertyKt {
+    // source: 'localDelegatedProperty.kt'
+    synthetic final static field $$delegatedProperties: kotlin.reflect.KProperty[]
+    static method <clinit>(): void
+    public final static @org.jetbrains.annotations.NotNull method foo(): java.lang.String
+    public final static @org.jetbrains.annotations.NotNull method getValue(@org.jetbrains.annotations.NotNull p0: java.lang.String, @org.jetbrains.annotations.Nullable p1: java.lang.Object, @org.jetbrains.annotations.Nullable p2: java.lang.Object): java.lang.String
+    public final static method setValue(@org.jetbrains.annotations.NotNull p0: java.lang.String, @org.jetbrains.annotations.Nullable p1: java.lang.Object, @org.jetbrains.annotations.Nullable p2: java.lang.Object, @org.jetbrains.annotations.NotNull p3: java.lang.String): void
+}

compiler/testData/codegen/bytecodeListing/delegatedProperty/localDelegatedProperty_ir.txt

@@ -0,0 +1,12 @@
+@kotlin.Metadata
+public final class LocalDelegatedPropertyKt {
+    // source: 'localDelegatedProperty.kt'
+    synthetic final static field $$delegatedProperties: kotlin.reflect.KProperty[]
+    static method <clinit>(): void
+    public synthetic final static method access$foo$lambda-0(p0: java.lang.String): java.lang.String
+    private final static method foo$lambda-0(p0: java.lang.String): java.lang.String
+    private final static method foo$lambda-1(p0: java.lang.String, p1: java.lang.String): void
+    public final static @org.jetbrains.annotations.NotNull method foo(): java.lang.String
+    public final static @org.jetbrains.annotations.NotNull method getValue(@org.jetbrains.annotations.NotNull p0: java.lang.String, @org.jetbrains.annotations.Nullable p1: java.lang.Object, @org.jetbrains.annotations.Nullable p2: java.lang.Object): java.lang.String
+    public final static method setValue(@org.jetbrains.annotations.NotNull p0: java.lang.String, @org.jetbrains.annotations.Nullable p1: java.lang.Object, @org.jetbrains.annotations.Nullable p2: java.lang.Object, @org.jetbrains.annotations.NotNull p3: java.lang.String): void
+}