public void FailsTypeCheckingForIncorrectNumberOfArguments()
{
var twoArgsToInteger = NamedType.Function(new[] { NamedType.Boolean, NamedType.Integer }, NamedType.Integer);
ShouldFailTypeChecking("foo(true, 1, false)", foo => twoArgsToInteger).WithError(
"Type mismatch: expected System.Func<bool, int, int>, found System.Func<bool, int, bool, int>.", 1, 1);
}
public Expression TypeCheck(Call call, Scope scope)
{
var position = call.Position;
var callable = call.Callable;
var arguments = call.Arguments;
var isOperator = call.IsOperator;
var typedCallable = TypeCheck(callable, scope);
var typedArguments = TypeCheck(arguments, scope);
var calleeType = typedCallable.Type;
var calleeFunctionType = calleeType as NamedType;
if (calleeFunctionType == null || calleeFunctionType.Name != "System.Func")
{
LogError(CompilerError.ObjectNotCallable(position));
return(call);
}
var returnType = calleeType.GenericArguments.Last();
var argumentTypes = typedArguments.Select(x => x.Type).ToVector();
Unify(position, calleeType, NamedType.Function(argumentTypes, returnType));
var callType = unifier.Normalize(returnType);
return(new Call(position, typedCallable, typedArguments, isOperator, callType));
}
public void FailsTypeCheckingForMismatchedArgumentTypes()
{
var integerToBoolean = NamedType.Function(new[] { NamedType.Integer }, NamedType.Boolean);
ShouldFailTypeChecking("even(true)", even => integerToBoolean).WithError(
"Type mismatch: expected int, found bool.", 1, 1);
}
public Expression TypeCheck(MethodInvocation methodInvocation, Scope scope)
{
var position = methodInvocation.Position;
var instance = methodInvocation.Instance;
var methodName = methodInvocation.MethodName;
var arguments = methodInvocation.Arguments;
var typedInstance = TypeCheck(instance, scope);
var instanceType = typedInstance.Type;
var instanceNamedType = instanceType as NamedType;
if (instanceNamedType == null)
{
LogError(CompilerError.AmbiguousMethodInvocation(position));
return(methodInvocation);
}
var typeMemberScope = new TypeMemberScope(typeRegistry.MembersOf(instanceNamedType));
//TODO: This block is suspiciously like Call type checking, but Callable/MethodName is evaluated in a special scope and the successful return is different.
var Callable = methodName;
//Attempt to treat this method invocation as an extension method, if we fail to find the method in the type member scope.
if (!typeMemberScope.Contains(Callable.Identifier))
{
var extensionMethodCall = TypeCheck(new Call(position, methodName, new[] { instance }.Concat(arguments)), scope);
if (extensionMethodCall != null)
{
return(extensionMethodCall);
}
}
var typedCallable = TypeCheck(Callable, typeMemberScope);
var typedArguments = TypeCheck(arguments, scope);
var calleeType = typedCallable.Type;
var calleeFunctionType = calleeType as NamedType;
if (calleeFunctionType == null || calleeFunctionType.Name != "System.Func")
{
LogError(CompilerError.ObjectNotCallable(position));
return(methodInvocation);
}
var returnType = calleeType.GenericArguments.Last();
var argumentTypes = typedArguments.Select(x => x.Type).ToVector();
Unify(position, calleeType, NamedType.Function(argumentTypes, returnType));
var callType = unifier.Normalize(returnType);
var typedMethodName = (Name)typedCallable;
return(new MethodInvocation(position, typedInstance, typedMethodName, typedArguments, callType));
}
public void HasAFunctionTypeWithReturnTypeEqualToTheTypeOfTheBodyExpression()
{
Type("fn () 1").ShouldEqual(NamedType.Function(Integer));
Type("fn () true").ShouldEqual(NamedType.Function(Boolean));
Type("fn () x", x => Integer).ShouldEqual(NamedType.Function(Integer));
Type("fn () x", x => Boolean).ShouldEqual(NamedType.Function(Boolean));
Type("fn (int x) x+1").ShouldEqual(NamedType.Function(new[] { Integer }, Integer));
Type("fn (int x) x+1 > 0").ShouldEqual(NamedType.Function(new[] { Integer }, Boolean));
}
public GlobalScope()
{
globals = new BindingDictionary();
DataType @int = NamedType.Integer;
DataType @bool = NamedType.Boolean;
DataType integerOperation = NamedType.Function(new[] { @int, @int }, @int);
DataType integerComparison = NamedType.Function(new[] { @int, @int }, @bool);
DataType booleanOperation = NamedType.Function(new[] { @bool, @bool }, @bool);
globals["<"] = integerComparison;
globals["<="] = integerComparison;
globals[">"] = integerComparison;
globals[">="] = integerComparison;
globals["=="] = integerComparison;
globals["!="] = integerComparison;
globals["+"] = integerOperation;
globals["*"] = integerOperation;
globals["/"] = integerOperation;
globals["-"] = integerOperation;
globals["&&"] = booleanOperation;
globals["||"] = booleanOperation;
globals["!"] = NamedType.Function(new[] { @bool }, @bool);
var T = TypeVariable.CreateGeneric(); //TypeVariable 0
var S = TypeVariable.CreateGeneric(); //TypeVariable 1
var enumerableT = NamedType.Enumerable(T);
var nullableT = NamedType.Nullable(T);
var vectorT = NamedType.Vector(T);
var enumerableS = NamedType.Enumerable(S);
globals["??"] = NamedType.Function(new DataType[] { nullableT, T }, T);
globals["Print"] = NamedType.Function(new[] { T }, NamedType.Void);
globals["Nullable"] = NamedType.Function(new[] { T }, nullableT);
globals["First"] = NamedType.Function(new[] { enumerableT }, T);
globals["Take"] = NamedType.Function(new[] { enumerableT, @int }, enumerableT);
globals["Skip"] = NamedType.Function(new[] { enumerableT, @int }, enumerableT);
globals["Any"] = NamedType.Function(new[] { enumerableT }, @bool);
globals["Count"] = NamedType.Function(new[] { enumerableT }, @int);
globals["Select"] = NamedType.Function(new[] { enumerableT, NamedType.Function(new[] { T }, S) }, enumerableS);
globals["Where"] = NamedType.Function(new[] { enumerableT, NamedType.Function(new[] { T }, @bool) }, enumerableT);
globals["Each"] = NamedType.Function(new[] { vectorT }, enumerableT);
globals[ReservedName.__index__] = NamedType.Function(new[] { vectorT, @int }, T);
globals[ReservedName.__slice__] = NamedType.Function(new[] { vectorT, @int, @int }, vectorT);
globals["Append"] = NamedType.Function(new DataType[] { vectorT, T }, vectorT);
globals["With"] = NamedType.Function(new[] { vectorT, @int, T }, vectorT);
}
public void CanCreateFullyTypedInstance()
{
var lambda = (Lambda)Parse("fn (x, int y, bool z) x+y>0 && z");
lambda.Parameters.ShouldHaveTypes(Unknown, Unknown, Unknown);
lambda.Body.Type.ShouldEqual(Unknown);
lambda.Type.ShouldEqual(Unknown);
var typedLambda = WithTypes(lambda);
typedLambda.Parameters.ShouldHaveTypes(Integer, Integer, Boolean);
typedLambda.Body.Type.ShouldEqual(Boolean);
typedLambda.Type.ShouldEqual(NamedType.Function(new[] { Integer, Integer, Boolean }, Boolean));
}
public void PassesTypeCheckingEvenWhenMethodNamesAreTheSameAsNamesInTheSurroundingScope()
{
var fooClass = "class Foo { int A() {0} int B() {2} }".ParseClass();
var typeRegistry = new TypeRegistry();
var constructorReturningFoo = NamedType.Constructor(new NamedType(fooClass));
typeRegistry.Add(fooClass);
var typeChecker = new TypeChecker(typeRegistry);
typeChecker.TypeCheck(fooClass, Scope(B => NamedType.Function(NamedType.Boolean))).Type.ShouldEqual(constructorReturningFoo);
typeChecker.HasErrors.ShouldBeFalse();
}
public void CanCreateFullyTypedInstance()
{
var node = Parse("bool foo(int x, int y, bool z) {x+y>0 && z}");
node.Parameters.ShouldHaveTypes(Unknown, Unknown, Unknown);
node.Body.Type.ShouldEqual(Unknown);
node.Type.ShouldEqual(Unknown);
var typeChecker = new TypeChecker();
var typedNode = typeChecker.TypeCheck(node, Scope());
typedNode.Parameters.ShouldHaveTypes(Integer, Integer, Boolean);
typedNode.Body.Type.ShouldEqual(Boolean);
typedNode.Type.ShouldEqual(NamedType.Function(new[] { Integer, Integer, Boolean }, Boolean));
}
public void CanCreateFullyTypedInstance()
{
var node = (MethodInvocation)Parse("math.Even(two)");
node.Instance.Type.ShouldEqual(Unknown);
node.MethodName.Type.ShouldEqual(Unknown);
node.Arguments.Single().Type.ShouldEqual(Unknown);
node.Type.ShouldEqual(Unknown);
var typedNode = WithTypes(node, math => mathType, two => Integer);
typedNode.Instance.Type.ShouldEqual(mathType);
typedNode.MethodName.Type.ShouldEqual(NamedType.Function(new[] { Integer }, Boolean));
typedNode.Arguments.Single().Type.ShouldEqual(Integer);
typedNode.Type.ShouldEqual(Boolean);
}
public void CanCreateFullyTypedInstance()
{
var call = (Call)Parse("func(yes, zero)");
call.Callable.Type.ShouldEqual(Unknown);
call.Arguments.ShouldHaveTypes(Unknown, Unknown);
call.Type.ShouldEqual(Unknown);
var typedCall = WithTypes(call,
func => Function(new[] { Boolean, Integer }, Integer),
yes => Boolean,
zero => Integer);
typedCall.Callable.Type.ShouldEqual(NamedType.Function(new[] { Boolean, Integer }, Integer));
typedCall.Arguments.ShouldHaveTypes(Boolean, Integer);
typedCall.Type.ShouldEqual(Integer);
}
public Expression TypeCheck(Lambda lambda, Scope scope)
{
var position = lambda.Position;
var parameters = lambda.Parameters;
var body = lambda.Body;
var typedParameters = GetTypedParameters(parameters).ToVector();
var localScope = CreateLocalScope(scope, typedParameters);
var typedBody = TypeCheck(body, localScope);
var normalizedParameters = NormalizeTypes(typedParameters);
var parameterTypes = normalizedParameters.Select(p => p.Type).ToArray();
return(new Lambda(position, normalizedParameters, typedBody, NamedType.Function(parameterTypes, typedBody.Type)));
}
public void ShouldGetMemberBindingsWhenGivenTheNamedTypeOfRegisteredClasses()
{
var math = "class Math { int Square(int x) {x*x} bool Zero(int x) {x==0} int Max(int* ints) {0} }".ParseClass();
var mathType = new NamedType(math);
typeRegistry.Add(math);
var members = typeRegistry.MembersOf(mathType);
var square = members[0];
var zero = members[1];
var max = members[2];
square.Identifier.ShouldEqual("Square");
square.Type.ShouldEqual(NamedType.Function(new[] { NamedType.Integer }, NamedType.Integer));
zero.Identifier.ShouldEqual("Zero");
zero.Type.ShouldEqual(NamedType.Function(new[] { NamedType.Integer }, NamedType.Boolean));
max.Identifier.ShouldEqual("Max");
max.Type.ShouldEqual(NamedType.Function(new[] { NamedType.Enumerable(NamedType.Integer) }, NamedType.Integer));
}
public void HasATypeIncludingInputTypesAndReturnType()
{
Type("int foo() {1}").ShouldEqual(NamedType.Function(Integer));
Type("bool foo(int x) {false}").ShouldEqual(NamedType.Function(new[] { Integer }, Boolean));
Type("int foo(int x, bool y) {1}").ShouldEqual(NamedType.Function(new[] { Integer, Boolean }, Integer));
}
public void FailsTypeCheckingForNamesThatAreNotConstructorNames()
{
ShouldFailTypeChecking("new Foo()", Foo => Integer).WithError("Cannot construct 'Foo' because it is not a type.", 1, 5);
ShouldFailTypeChecking("new Foo()", Foo => NamedType.Function(Integer)).WithError("Cannot construct 'Foo' because it is not a type.", 1, 5);
}
public void InfersParameterTypesFromUsages()
{
Type("fn (x) x+1").ShouldEqual(NamedType.Function(new[] { Integer }, Integer));
Type("fn (x, y) x+y").ShouldEqual(NamedType.Function(new[] { Integer, Integer }, Integer));
Type("fn (x) x+1 > 0").ShouldEqual(NamedType.Function(new[] { Integer }, Boolean));
}
public NamedType DeclaredType(Function function)
{
var parameterTypes = function.Parameters.Select(p => TypeOf(p.DeclaredTypeName)).ToArray();
return(NamedType.Function(parameterTypes, TypeOf(function.ReturnTypeName)));
}
private static DataType Function(IEnumerable <DataType> parameterTypes, DataType returnType)
{
return(NamedType.Function(parameterTypes, returnType));
}
public void EvaluatesBodyExpressionTypesInANewScopeIncludingParameters()
{
Type("int foo(int x) {x}").ShouldEqual(NamedType.Function(new[] { Integer }, Integer));
Type("bool foo(int x, int y, bool b) {x==y || b}").ShouldEqual(
NamedType.Function(new[] { Integer, Integer, Boolean }, Boolean));
}