FE 1.0: introduce DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER error

#KT-24643 Fixed

compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirOldFrontendDiagnosticsTestGenerated.java

@@ -7119,6 +7119,18 @@ public class FirOldFrontendDiagnosticsTestGenerated extends AbstractFirDiagnosti
                 runTest("compiler/testData/diagnostics/tests/delegatedProperty/typeMismatchForThisGetParameter.kt");
             }
 
+            @Test
+            @TestMetadata("useTypeParameterOfExtensionProperty.kt")
+            public void testUseTypeParameterOfExtensionProperty() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty.kt");
+            }
+
+            @Test
+            @TestMetadata("useTypeParameterOfExtensionProperty_Disabled.kt")
+            public void testUseTypeParameterOfExtensionProperty_Disabled() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty_Disabled.kt");
+            }
+
             @Test
             @TestMetadata("wrongCountOfParametersInGet.kt")
             public void testWrongCountOfParametersInGet() throws Exception {

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -603,6 +603,8 @@ public interface Errors {
     DiagnosticFactory0<KtExpression> SETTER_PARAMETER_WITH_DEFAULT_VALUE = DiagnosticFactory0.create(ERROR);
 
     DiagnosticFactory2<KtTypeReference, KotlinType, KotlinType> WRONG_SETTER_PARAMETER_TYPE = DiagnosticFactory2.create(ERROR);
+    DiagnosticFactory1<KtPropertyDelegate, String> DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER = DiagnosticFactory1.create(ERROR);
+    DiagnosticFactory1<KtPropertyDelegate, String> DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER_WARNING = DiagnosticFactory1.create(WARNING);
 
     // Function-specific
 

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -477,6 +477,8 @@ public class DefaultErrorMessages {
         MAP.put(USELESS_NULLABLE_CHECK, "Non-null type is checked for instance of nullable type");
         MAP.put(USELESS_IS_CHECK, "Check for instance is always ''{0}''", TO_STRING);
         MAP.put(WRONG_SETTER_PARAMETER_TYPE, "Setter parameter type must be equal to the type of the property, i.e. ''{0}''", RENDER_TYPE, RENDER_TYPE);
+        MAP.put(DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER, "It's forbidden using extension property type parameter ''{0}'' in delegate", TO_STRING);
+        MAP.put(DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER_WARNING, "Deprecation: delegate shouldn't use extension property type parameter ''{0}''", TO_STRING);
         MAP.put(WRONG_GETTER_RETURN_TYPE, "Getter return type must be equal to the type of the property, i.e. ''{0}''", RENDER_TYPE, RENDER_TYPE);
         MAP.put(WRONG_SETTER_RETURN_TYPE, "Setter return type must be Unit");
         MAP.put(NO_COMPANION_OBJECT, "Classifier ''{0}'' does not have a companion object, and thus must be initialized here", NAME);

compiler/frontend/src/org/jetbrains/kotlin/resolve/DeclarationsChecker.kt

@@ -712,6 +712,19 @@ class DeclarationsChecker(
                 trace.report(DELEGATED_PROPERTY_IN_INTERFACE.on(delegate))
             } else if (isExpect) {
                 trace.report(EXPECTED_DELEGATED_PROPERTY.on(delegate))
+            } else if (property.receiverTypeReference != null) {
+                val delegatedPropertyResolvedCall = trace.get(DELEGATED_PROPERTY_RESOLVED_CALL, propertyDescriptor.getter)
+                val dispatchReceiverType = delegatedPropertyResolvedCall?.dispatchReceiver?.type
+                val usedParameter = propertyDescriptor.typeParameters.find { typeParameter ->
+                    dispatchReceiverType?.contains { it.constructor == typeParameter.typeConstructor } == true
+                }
+                if (usedParameter != null) {
+                    if (languageVersionSettings.supportsFeature(LanguageFeature.ForbidUsingExtensionPropertyTypeParameterInDelegate)) {
+                        trace.report(DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER.on(delegate, usedParameter.name.asString()))
+                    } else {
+                        trace.report(DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER_WARNING.on(delegate, usedParameter.name.asString()))
+                    }
+                }
             }
         } else {
             val isUninitialized = trace.bindingContext.get(BindingContext.IS_UNINITIALIZED, propertyDescriptor) ?: false

compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty.fir.kt

@@ -0,0 +1,16 @@
+// !LANGUAGE: +ForbidUsingExtensionPropertyTypeParameterInDelegate
+
+class Delegate<T : Any> {
+    private var v: T? = null
+    operator fun getValue(thisRef: Any?, kp: Any?): T = v!!
+    operator fun setValue(thisRef: Any?, kp: Any?, newValue: T) { v = newValue }
+}
+
+var <T : Any> List<T>.foo by Delegate<T>()
+
+fun useString(s: String) {}
+
+fun main(listInt: List<Int>, listStr: List<String>) {
+    listInt.foo = 42
+    useString(listStr.foo) // CCE
+}

compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty.kt

@@ -0,0 +1,16 @@
+// !LANGUAGE: +ForbidUsingExtensionPropertyTypeParameterInDelegate
+
+class Delegate<T : Any> {
+    private var v: T? = null
+    operator fun getValue(thisRef: Any?, kp: Any?): T = v!!
+    operator fun setValue(thisRef: Any?, kp: Any?, newValue: T) { v = newValue }
+}
+
+var <T : Any> List<T>.foo <!DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER!>by Delegate<T>()<!>
+
+fun useString(s: String) {}
+
+fun main(listInt: List<Int>, listStr: List<String>) {
+    listInt.foo = 42
+    useString(listStr.foo) // CCE
+}

compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty.txt

@@ -0,0 +1,15 @@
+package
+
+public var </*0*/ T : kotlin.Any> kotlin.collections.List<T>.foo: T
+public fun main(/*0*/ listInt: kotlin.collections.List<kotlin.Int>, /*1*/ listStr: kotlin.collections.List<kotlin.String>): kotlin.Unit
+public fun useString(/*0*/ s: kotlin.String): kotlin.Unit
+
+public final class Delegate</*0*/ T : kotlin.Any> {
+    public constructor Delegate</*0*/ T : kotlin.Any>()
+    private final var v: T?
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kp: kotlin.Any?): T
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final operator fun setValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kp: kotlin.Any?, /*2*/ newValue: T): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty_Disabled.fir.kt

@@ -0,0 +1,16 @@
+// !LANGUAGE: -ForbidUsingExtensionPropertyTypeParameterInDelegate
+
+class Delegate<T : Any> {
+    private var v: T? = null
+    operator fun getValue(thisRef: Any?, kp: Any?): T = v!!
+    operator fun setValue(thisRef: Any?, kp: Any?, newValue: T) { v = newValue }
+}
+
+var <T : Any> List<T>.foo by Delegate<T>()
+
+fun useString(s: String) {}
+
+fun main(listInt: List<Int>, listStr: List<String>) {
+    listInt.foo = 42
+    useString(listStr.foo) // CCE
+}

compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty_Disabled.kt

@@ -0,0 +1,16 @@
+// !LANGUAGE: -ForbidUsingExtensionPropertyTypeParameterInDelegate
+
+class Delegate<T : Any> {
+    private var v: T? = null
+    operator fun getValue(thisRef: Any?, kp: Any?): T = v!!
+    operator fun setValue(thisRef: Any?, kp: Any?, newValue: T) { v = newValue }
+}
+
+var <T : Any> List<T>.foo <!DELEGATE_USES_EXTENSION_PROPERTY_TYPE_PARAMETER_WARNING!>by Delegate<T>()<!>
+
+fun useString(s: String) {}
+
+fun main(listInt: List<Int>, listStr: List<String>) {
+    listInt.foo = 42
+    useString(listStr.foo) // CCE
+}

compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty_Disabled.txt

@@ -0,0 +1,15 @@
+package
+
+public var </*0*/ T : kotlin.Any> kotlin.collections.List<T>.foo: T
+public fun main(/*0*/ listInt: kotlin.collections.List<kotlin.Int>, /*1*/ listStr: kotlin.collections.List<kotlin.String>): kotlin.Unit
+public fun useString(/*0*/ s: kotlin.String): kotlin.Unit
+
+public final class Delegate</*0*/ T : kotlin.Any> {
+    public constructor Delegate</*0*/ T : kotlin.Any>()
+    private final var v: T?
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public final operator fun getValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kp: kotlin.Any?): T
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public final operator fun setValue(/*0*/ thisRef: kotlin.Any?, /*1*/ kp: kotlin.Any?, /*2*/ newValue: T): kotlin.Unit
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java

@@ -7125,6 +7125,18 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/delegatedProperty/typeMismatchForThisGetParameter.kt");
             }
 
+            @Test
+            @TestMetadata("useTypeParameterOfExtensionProperty.kt")
+            public void testUseTypeParameterOfExtensionProperty() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty.kt");
+            }
+
+            @Test
+            @TestMetadata("useTypeParameterOfExtensionProperty_Disabled.kt")
+            public void testUseTypeParameterOfExtensionProperty_Disabled() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/delegatedProperty/useTypeParameterOfExtensionProperty_Disabled.kt");
+            }
+
             @Test
             @TestMetadata("wrongCountOfParametersInGet.kt")
             public void testWrongCountOfParametersInGet() throws Exception {

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -165,6 +165,7 @@ enum class LanguageFeature(
     TypeEnhancementImprovementsInStrictMode(KOTLIN_1_6),
     ProhibitJvmFieldOnOverrideFromInterfaceInPrimaryConstructor(KOTLIN_1_6, kind = BUG_FIX),
     PrivateInFileEffectiveVisibility(KOTLIN_1_6, kind = BUG_FIX),
+    ForbidUsingExtensionPropertyTypeParameterInDelegate(KOTLIN_1_6, kind = BUG_FIX),
 
     // Temporarily disabled, see KT-27084/KT-22379
     SoundSmartcastFromLoopConditionForLoopAssignedVariables(sinceVersion = null, kind = BUG_FIX),