Add support for max parameter count (internal #128)

runtime/account_test.go

@@ -2361,7 +2361,7 @@ func TestGetAuthAccount(t *testing.T) {
 
 		errs := checker.RequireCheckerErrors(t, err, 1)
 
-		assert.IsType(t, &sema.ArgumentCountError{}, errs[0])
+		assert.IsType(t, &sema.InsufficientArgumentsError{}, errs[0])
 	})
 
 	t.Run("too many args", func(t *testing.T) {
@@ -2388,7 +2388,7 @@ func TestGetAuthAccount(t *testing.T) {
 		)
 		errs := checker.RequireCheckerErrors(t, err, 1)
 
-		assert.IsType(t, &sema.ArgumentCountError{}, errs[0])
+		assert.IsType(t, &sema.ExcessiveArgumentsError{}, errs[0])
 	})
 
 	t.Run("transaction", func(t *testing.T) {

runtime/interpreter/interpreter.go

@@ -423,12 +423,15 @@ func (interpreter *Interpreter) InvokeExternally(
 
 	if argumentCount != parameterCount {
 
-		// if the function has defined optional parameters,
-		// then the provided arguments must be equal to or greater than
-		// the number of required parameters.
-		if functionType.RequiredArgumentCount == nil ||
-			argumentCount < *functionType.RequiredArgumentCount {
+		if argumentCount < functionType.Arity.MinCount(parameterCount) {
+			return nil, ArgumentCountError{
+				ParameterCount: parameterCount,
+				ArgumentCount:  argumentCount,
+			}
+		}
 
+		maxCount := functionType.Arity.MaxCount(parameterCount)
+		if maxCount != nil && argumentCount > *maxCount {
 			return nil, ArgumentCountError{
 				ParameterCount: parameterCount,
 				ArgumentCount:  argumentCount,
@@ -1065,7 +1068,6 @@ func (interpreter *Interpreter) declareNonEnumCompositeValue(
 		ReturnTypeAnnotation: sema.TypeAnnotation{
 			Type: compositeType,
 		},
-		RequiredArgumentCount: nil,
 	}
 
 	var initializerFunction FunctionValue

runtime/sema/authaccount.go

@@ -23,7 +23,7 @@ package sema
 var AuthAccountTypeLinkAccountFunctionTypePathParameterTypeAnnotation = AuthAccountTypeLinkAccountFunctionType.Parameters[0].TypeAnnotation
 
 func init() {
-	AuthAccountContractsTypeAddFunctionType.RequiredArgumentCount = RequiredArgumentCount(2)
+	AuthAccountContractsTypeAddFunctionType.Arity = &Arity{Min: 2}
 	AuthAccountTypeGetCapabilityFunctionTypeParameterT.Optional = true
 	PublicAccountTypeGetCapabilityFunctionTypeParameterT.Optional = true
 }

runtime/sema/check_invocation_expression.go

@@ -374,7 +374,7 @@ func (checker *Checker) checkInvocation(
 	returnType Type,
 ) {
 	parameterCount := len(functionType.Parameters)
-	requiredArgumentCount := functionType.RequiredArgumentCount
+	arity := functionType.Arity
 	typeParameterCount := len(functionType.TypeParameters)
 
 	// Check the type arguments and bind them to type parameters
@@ -421,7 +421,7 @@ func (checker *Checker) checkInvocation(
 	checker.checkInvocationArgumentCount(
 		argumentCount,
 		parameterCount,
-		requiredArgumentCount,
+		arity,
 		invocationExpression,
 	)
 
@@ -592,23 +592,28 @@ func (checker *Checker) checkInvocationRequiredArgument(
 func (checker *Checker) checkInvocationArgumentCount(
 	argumentCount int,
 	parameterCount int,
-	requiredArgumentCount *int,
+	arity *Arity,
 	pos ast.HasPosition,
 ) {
-
-	if argumentCount == parameterCount {
+	minCount := arity.MinCount(parameterCount)
+	if argumentCount < minCount {
+		checker.report(
+			&InsufficientArgumentsError{
+				MinCount:    minCount,
+				ActualCount: argumentCount,
+				Range:       ast.NewRangeFromPositioned(checker.memoryGauge, pos),
+			},
+		)
 		return
 	}
 
-	// TODO: improve
-	if requiredArgumentCount == nil ||
-		argumentCount < *requiredArgumentCount {
-
+	maxCount := arity.MaxCount(parameterCount)
+	if maxCount != nil && argumentCount > *maxCount {
 		checker.report(
-			&ArgumentCountError{
-				ParameterCount: parameterCount,
-				ArgumentCount:  argumentCount,
-				Range:          ast.NewRangeFromPositioned(checker.memoryGauge, pos),
+			&ExcessiveArgumentsError{
+				MaxCount:    *maxCount,
+				ActualCount: argumentCount,
+				Range:       ast.NewRangeFromPositioned(checker.memoryGauge, pos),
 			},
 		)
 	}

runtime/sema/errors.go

@@ -411,31 +411,59 @@ func (e *NotCallableError) Error() string {
 	)
 }
 
-// ArgumentCountError
+// InsufficientArgumentsError
 
-type ArgumentCountError struct {
-	ParameterCount int
-	ArgumentCount  int
+type InsufficientArgumentsError struct {
+	MinCount    int
+	ActualCount int
 	ast.Range
 }
 
-var _ SemanticError = &ArgumentCountError{}
-var _ errors.UserError = &ArgumentCountError{}
-var _ errors.SecondaryError = &ArgumentCountError{}
+var _ SemanticError = &InsufficientArgumentsError{}
+var _ errors.UserError = &InsufficientArgumentsError{}
+var _ errors.SecondaryError = &InsufficientArgumentsError{}
 
-func (*ArgumentCountError) isSemanticError() {}
+func (*InsufficientArgumentsError) isSemanticError() {}
 
-func (*ArgumentCountError) IsUserError() {}
+func (*InsufficientArgumentsError) IsUserError() {}
 
-func (e *ArgumentCountError) Error() string {
-	return "incorrect number of arguments"
+func (e *InsufficientArgumentsError) Error() string {
+	return "too few arguments"
 }
 
-func (e *ArgumentCountError) SecondaryError() string {
+func (e *InsufficientArgumentsError) SecondaryError() string {
 	return fmt.Sprintf(
-		"expected %d, got %d",
-		e.ParameterCount,
-		e.ArgumentCount,
+		"expected at least %d, got %d",
+		e.MinCount,
+		e.ActualCount,
+	)
+}
+
+// ExcessiveArgumentsError
+
+type ExcessiveArgumentsError struct {
+	MaxCount    int
+	ActualCount int
+	ast.Range
+}
+
+var _ SemanticError = &ExcessiveArgumentsError{}
+var _ errors.UserError = &ExcessiveArgumentsError{}
+var _ errors.SecondaryError = &ExcessiveArgumentsError{}
+
+func (*ExcessiveArgumentsError) isSemanticError() {}
+
+func (*ExcessiveArgumentsError) IsUserError() {}
+
+func (e *ExcessiveArgumentsError) Error() string {
+	return "too many arguments"
+}
+
+func (e *ExcessiveArgumentsError) SecondaryError() string {
+	return fmt.Sprintf(
+		"expected up to %d, got %d",
+		e.MaxCount,
+		e.ActualCount,
 	)
 }
 

runtime/sema/type.go

@@ -2655,10 +2655,38 @@ func formatFunctionType(
 	return builder.String()
 }
 
+// Arity
+
+type Arity struct {
+	Min int
+	Max int
+}
+
+func (arity *Arity) MinCount(parameterCount int) int {
+	minCount := parameterCount
+	if arity != nil {
+		minCount = arity.Min
+	}
+
+	return minCount
+}
+
+func (arity *Arity) MaxCount(parameterCount int) *int {
+	maxCount := parameterCount
+	if arity != nil {
+		if arity.Max < parameterCount {
+			return nil
+		}
+		maxCount = arity.Max
+	}
+
+	return &maxCount
+}
+
 // FunctionType
 type FunctionType struct {
 	ReturnTypeAnnotation     TypeAnnotation
-	RequiredArgumentCount    *int
+	Arity                    *Arity
 	ArgumentExpressionsCheck ArgumentExpressionsCheck
 	Members                  *StringMemberOrderedMap
 	TypeParameters           []*TypeParameter
@@ -2670,10 +2698,6 @@ type FunctionType struct {
 
 var _ Type = &FunctionType{}
 
-func RequiredArgumentCount(count int) *int {
-	return &count
-}
-
 func (*FunctionType) IsType() {}
 
 func (t *FunctionType) Tag() TypeTag {
@@ -2994,10 +3018,10 @@ func (t *FunctionType) RewriteWithRestrictedTypes() (Type, bool) {
 		}
 
 		return &FunctionType{
-			TypeParameters:        rewrittenTypeParameters,
-			Parameters:            rewrittenParameters,
-			ReturnTypeAnnotation:  NewTypeAnnotation(rewrittenReturnType),
-			RequiredArgumentCount: t.RequiredArgumentCount,
+			TypeParameters:       rewrittenTypeParameters,
+			Parameters:           rewrittenParameters,
+			ReturnTypeAnnotation: NewTypeAnnotation(rewrittenReturnType),
+			Arity:                t.Arity,
 		}, true
 	} else {
 		return t, false
@@ -3106,9 +3130,9 @@ func (t *FunctionType) Resolve(typeArguments *TypeParameterTypeOrderedMap) Type
 	}
 
 	return &FunctionType{
-		Parameters:            newParameters,
-		ReturnTypeAnnotation:  NewTypeAnnotation(newReturnType),
-		RequiredArgumentCount: t.RequiredArgumentCount,
+		Parameters:           newParameters,
+		ReturnTypeAnnotation: NewTypeAnnotation(newReturnType),
+		Arity:                t.Arity,
 	}
 
 }

runtime/stdlib/assert.go

@@ -50,7 +50,8 @@ var assertFunctionType = &sema.FunctionType{
 	ReturnTypeAnnotation: sema.NewTypeAnnotation(
 		sema.VoidType,
 	),
-	RequiredArgumentCount: sema.RequiredArgumentCount(1),
+	// `message` parameter is optional
+	Arity: &sema.Arity{Min: 1, Max: 2},
 }
 
 var AssertFunction = NewStandardLibraryFunction(