Merge pull request #2789 from onflow/sainati/ban-custom-destructors

Remove support for custom destructors

encoding/ccf/ccf_test.go

@@ -5218,10 +5218,6 @@ func TestEncodeResource(t *testing.T) {
 					init(bar: @Bar) {
 						self.bar <- bar
 					}
-
-					destroy() {
-						destroy self.bar
-					}
 				}
 
 				fun main(): @Foo {

encoding/json/encoding_test.go

@@ -1264,10 +1264,6 @@ func TestEncodeResource(t *testing.T) {
                 init(bar: @Bar) {
                     self.bar <- bar
                 }
-
-                destroy() {
-                    destroy self.bar
-                }
             }
 
             fun main(): @Foo {

runtime/ast/memberindices.go

@@ -37,10 +37,6 @@ type memberIndices struct {
 	_specialFunctions []*SpecialFunctionDeclaration
 	// Use `Initializers()` instead
 	_initializers []*SpecialFunctionDeclaration
-	// Semantically only one destructor is allowed,
-	// but the program might illegally declare multiple.
-	// Use `Destructors()` instead
-	_destructors []*SpecialFunctionDeclaration
 	// Use `Functions()`
 	_functions []*FunctionDeclaration
 	// Use `FunctionsByIdentifier()` instead
@@ -109,11 +105,6 @@ func (i *memberIndices) Initializers(declarations []Declaration) []*SpecialFunct
 	return i._initializers
 }
 
-func (i *memberIndices) Destructors(declarations []Declaration) []*SpecialFunctionDeclaration {
-	i.once.Do(i.initializer(declarations))
-	return i._destructors
-}
-
 func (i *memberIndices) Fields(declarations []Declaration) []*FieldDeclaration {
 	i.once.Do(i.initializer(declarations))
 	return i._fields
@@ -175,7 +166,6 @@ func (i *memberIndices) init(declarations []Declaration) {
 	i._functionsByIdentifier = make(map[string]*FunctionDeclaration)
 
 	i._specialFunctions = make([]*SpecialFunctionDeclaration, 0)
-	i._destructors = make([]*SpecialFunctionDeclaration, 0)
 	i._initializers = make([]*SpecialFunctionDeclaration, 0)
 
 	i._composites = make([]*CompositeDeclaration, 0)
@@ -211,8 +201,6 @@ func (i *memberIndices) init(declarations []Declaration) {
 			switch declaration.Kind {
 			case common.DeclarationKindInitializer:
 				i._initializers = append(i._initializers, declaration)
-			case common.DeclarationKindDestructor:
-				i._destructors = append(i._destructors, declaration)
 			}
 
 		case *EntitlementDeclaration:

runtime/ast/memberindices_test.go

@@ -54,10 +54,7 @@ func TestMemberIndices(t *testing.T) {
 	specialFunctionA := &SpecialFunctionDeclaration{
 		Kind: common.DeclarationKindInitializer,
 	}
-	specialFunctionB := &SpecialFunctionDeclaration{
-		Kind: common.DeclarationKindDestructor,
-	}
-	specialFunctionC := &SpecialFunctionDeclaration{}
+	specialFunctionB := &SpecialFunctionDeclaration{}
 
 	compositeA := &CompositeDeclaration{
 		Identifier: Identifier{Identifier: "A"},
@@ -98,7 +95,6 @@ func TestMemberIndices(t *testing.T) {
 			interfaceB,
 			compositeA,
 			functionB,
-			specialFunctionC,
 			compositeB,
 			specialFunctionA,
 			interfaceA,
@@ -141,7 +137,6 @@ func TestMemberIndices(t *testing.T) {
 			require.Equal(t,
 				[]*SpecialFunctionDeclaration{
 					specialFunctionB,
-					specialFunctionC,
 					specialFunctionA,
 				},
 				members.SpecialFunctions(),

runtime/ast/members.go

@@ -116,19 +116,6 @@ func (m *Members) Initializers() []*SpecialFunctionDeclaration {
 	return m.indices.Initializers(m.declarations)
 }
 
-func (m *Members) Destructors() []*SpecialFunctionDeclaration {
-	return m.indices.Destructors(m.declarations)
-}
-
-// Destructor returns the first destructor, if any
-func (m *Members) Destructor() *SpecialFunctionDeclaration {
-	destructors := m.Destructors()
-	if len(destructors) == 0 {
-		return nil
-	}
-	return destructors[0]
-}
-
 func (m *Members) FieldPosition(name string, compositeKind common.CompositeKind) Position {
 	if compositeKind == common.CompositeKindEvent {
 		parameters := m.Initializers()[0].FunctionDeclaration.ParameterList.ParametersByIdentifier()

runtime/common/declarationkind.go

@@ -44,7 +44,6 @@ const (
 	DeclarationKindEvent
 	DeclarationKindField
 	DeclarationKindInitializer
-	DeclarationKindDestructor
 	DeclarationKindStructureInterface
 	DeclarationKindResourceInterface
 	DeclarationKindContractInterface
@@ -117,8 +116,6 @@ func (k DeclarationKind) Name() string {
 		return "field"
 	case DeclarationKindInitializer:
 		return "initializer"
-	case DeclarationKindDestructor:
-		return "destructor"
 	case DeclarationKindAttachment:
 		return "attachment"
 	case DeclarationKindStructureInterface:
@@ -176,8 +173,6 @@ func (k DeclarationKind) Keywords() string {
 		return "event"
 	case DeclarationKindInitializer:
 		return "init"
-	case DeclarationKindDestructor:
-		return "destroy"
 	case DeclarationKindAttachment:
 		return "attachment"
 	case DeclarationKindStructureInterface:

runtime/convertValues_test.go

@@ -1687,10 +1687,6 @@ func TestRuntimeExportNestedResourceValueFromScript(t *testing.T) {
             init(bar: @Bar) {
                 self.bar <- bar
             }
-
-            destroy() {
-                destroy self.bar
-            }
         }
 
         access(all) fun main(): @Foo {

runtime/ft_test.go

@@ -274,10 +274,6 @@ access(all) contract FlowToken: FungibleToken {
             vault.balance = 0.0
             destroy vault
         }
-
-        destroy() {
-            FlowToken.totalSupply = FlowToken.totalSupply - self.balance
-        }
     }
 
     // createEmptyVault

runtime/interpreter/interpreter.go

@@ -43,14 +43,6 @@ import (
 
 //
 
-var emptyImpureFunctionType = sema.NewSimpleFunctionType(
-	sema.FunctionPurityImpure,
-	nil,
-	sema.VoidTypeAnnotation,
-)
-
-//
-
 type getterSetter struct {
 	target Value
 	// allowMissing may be true when the got value is nil.
@@ -183,7 +175,6 @@ type CompositeValueFunctionsHandlerFunc func(
 // these are the "leaf" nodes in the call chain, and are functions.
 type CompositeTypeCode struct {
 	CompositeFunctions map[string]FunctionValue
-	DestructorFunction FunctionValue
 }
 
 type FunctionWrapper = func(inner FunctionValue) FunctionValue
@@ -195,7 +186,6 @@ type FunctionWrapper = func(inner FunctionValue) FunctionValue
 // i.e. they wrap the functions / function wrappers that inherit them.
 type WrapperCode struct {
 	InitializerFunctionWrapper FunctionWrapper
-	DestructorFunctionWrapper  FunctionWrapper
 	FunctionWrappers           map[string]FunctionWrapper
 	Functions                  map[string]FunctionValue
 }
@@ -1136,12 +1126,6 @@ func (interpreter *Interpreter) declareNonEnumCompositeValue(
 		}
 	}
 
-	var destructorFunction FunctionValue
-	compositeDestructorFunction := interpreter.compositeDestructorFunction(declaration, lexicalScope)
-	if compositeDestructorFunction != nil {
-		destructorFunction = compositeDestructorFunction
-	}
-
 	functions := interpreter.compositeFunctions(declaration, lexicalScope)
 
 	wrapFunctions := func(code WrapperCode) {
@@ -1155,15 +1139,6 @@ func (interpreter *Interpreter) declareNonEnumCompositeValue(
 			initializerFunction = initializerFunctionWrapper(initializerFunction)
 		}
 
-		// Wrap destructor
-
-		destructorFunctionWrapper :=
-			code.DestructorFunctionWrapper
-
-		if destructorFunctionWrapper != nil {
-			destructorFunction = destructorFunctionWrapper(destructorFunction)
-		}
-
 		// Apply default functions, if conforming type does not provide the function
 
 		// Iterating over the map in a non-deterministic way is OK,
@@ -1198,7 +1173,6 @@ func (interpreter *Interpreter) declareNonEnumCompositeValue(
 	}
 
 	interpreter.SharedState.typeCodes.CompositeCodes[compositeType.ID()] = CompositeTypeCode{
-		DestructorFunction: destructorFunction,
 		CompositeFunctions: functions,
 	}
 
@@ -1288,7 +1262,6 @@ func (interpreter *Interpreter) declareNonEnumCompositeValue(
 
 				value.injectedFields = injectedFields
 				value.Functions = functions
-				value.Destructor = destructorFunction
 
 				var self MemberAccessibleValue = value
 				if declaration.Kind() == common.CompositeKindAttachment {
@@ -1544,49 +1517,6 @@ func (interpreter *Interpreter) compositeInitializerFunction(
 	)
 }
 
-func (interpreter *Interpreter) compositeDestructorFunction(
-	compositeDeclaration ast.CompositeLikeDeclaration,
-	lexicalScope *VariableActivation,
-) *InterpretedFunctionValue {
-
-	destructor := compositeDeclaration.DeclarationMembers().Destructor()
-	if destructor == nil {
-		return nil
-	}
-
-	statements := destructor.FunctionDeclaration.FunctionBlock.Block.Statements
-
-	var preConditions ast.Conditions
-
-	conditions := destructor.FunctionDeclaration.FunctionBlock.PreConditions
-	if conditions != nil {
-		preConditions = *conditions
-	}
-
-	var beforeStatements []ast.Statement
-	var rewrittenPostConditions ast.Conditions
-
-	postConditions := destructor.FunctionDeclaration.FunctionBlock.PostConditions
-	if postConditions != nil {
-		postConditionsRewrite :=
-			interpreter.Program.Elaboration.PostConditionsRewrite(postConditions)
-
-		beforeStatements = postConditionsRewrite.BeforeStatements
-		rewrittenPostConditions = postConditionsRewrite.RewrittenPostConditions
-	}
-
-	return NewInterpretedFunctionValue(
-		interpreter,
-		nil,
-		emptyImpureFunctionType,
-		lexicalScope,
-		beforeStatements,
-		preConditions,
-		statements,
-		rewrittenPostConditions,
-	)
-}
-
 func (interpreter *Interpreter) defaultFunctions(
 	members *ast.Members,
 	lexicalScope *VariableActivation,
@@ -2250,13 +2180,11 @@ func (interpreter *Interpreter) declareInterface(
 		interfaceType.InitializerParameters,
 		lexicalScope,
 	)
-	destructorFunctionWrapper := interpreter.destructorFunctionWrapper(declaration.Members, lexicalScope)
 	functionWrappers := interpreter.functionWrappers(declaration.Members, lexicalScope)
 	defaultFunctions := interpreter.defaultFunctions(declaration.Members, lexicalScope)
 
 	interpreter.SharedState.typeCodes.InterfaceCodes[typeID] = WrapperCode{
 		InitializerFunctionWrapper: initializerFunctionWrapper,
-		DestructorFunctionWrapper:  destructorFunctionWrapper,
 		FunctionWrappers:           functionWrappers,
 		Functions:                  defaultFunctions,
 	}
@@ -2290,27 +2218,6 @@ func (interpreter *Interpreter) initializerFunctionWrapper(
 	)
 }
 
-var voidFunctionType = &sema.FunctionType{
-	ReturnTypeAnnotation: sema.VoidTypeAnnotation,
-}
-
-func (interpreter *Interpreter) destructorFunctionWrapper(
-	members *ast.Members,
-	lexicalScope *VariableActivation,
-) FunctionWrapper {
-
-	destructor := members.Destructor()
-	if destructor == nil {
-		return nil
-	}
-
-	return interpreter.functionConditionsWrapper(
-		destructor.FunctionDeclaration,
-		voidFunctionType,
-		lexicalScope,
-	)
-}
-
 func (interpreter *Interpreter) functionConditionsWrapper(
 	declaration *ast.FunctionDeclaration,
 	functionType *sema.FunctionType,