package org.jetbrains.jet.lang.types; import com.intellij.psi.tree.IElementType; import org.jetbrains.annotations.NotNull; import org.jetbrains.annotations.Nullable; import org.jetbrains.jet.JetNodeTypes; import org.jetbrains.jet.lang.JetSemanticServices; import org.jetbrains.jet.lang.psi.*; import org.jetbrains.jet.lang.resolve.*; import org.jetbrains.jet.lexer.JetTokens; import java.util.*; /** * @author abreslav */ public class JetTypeInferrer { private static final Map unaryOperationNames = new HashMap(); static { unaryOperationNames.put(JetTokens.PLUSPLUS, "inc"); unaryOperationNames.put(JetTokens.MINUSMINUS, "dec"); unaryOperationNames.put(JetTokens.PLUS, "plus"); unaryOperationNames.put(JetTokens.MINUS, "minus"); unaryOperationNames.put(JetTokens.EXCL, "not"); } private static final Map binaryOperationNames = new HashMap(); static { binaryOperationNames.put(JetTokens.MUL, "times"); binaryOperationNames.put(JetTokens.PLUS, "plus"); binaryOperationNames.put(JetTokens.MINUS, "minus"); binaryOperationNames.put(JetTokens.DIV, "div"); binaryOperationNames.put(JetTokens.PERC, "mod"); binaryOperationNames.put(JetTokens.ARROW, "arrow"); binaryOperationNames.put(JetTokens.RANGE, "rangeTo"); } private static final Set comparisonOperations = new HashSet(Arrays.asList(JetTokens.LT, JetTokens.GT, JetTokens.LTEQ, JetTokens.GTEQ)); private static final Set equalsOperations = new HashSet(Arrays.asList(JetTokens.EQEQ, JetTokens.EXCLEQ)); private static final Set inOperations = new HashSet(Arrays.asList(JetTokens.IN_KEYWORD, JetTokens.NOT_IN)); private static final Map assignmentOperationNames = new HashMap(); static { assignmentOperationNames.put(JetTokens.MULTEQ, "timesAssign"); assignmentOperationNames.put(JetTokens.DIVEQ, "divAssign"); assignmentOperationNames.put(JetTokens.PERCEQ, "modAssign"); assignmentOperationNames.put(JetTokens.PLUSEQ, "plusAssign"); assignmentOperationNames.put(JetTokens.MINUSEQ, "minusAssign"); } private static final Map assignmentOperationCounterparts = new HashMap(); static { assignmentOperationCounterparts.put(JetTokens.MULTEQ, JetTokens.MUL); assignmentOperationCounterparts.put(JetTokens.DIVEQ, JetTokens.DIV); assignmentOperationCounterparts.put(JetTokens.PERCEQ, JetTokens.PERC); assignmentOperationCounterparts.put(JetTokens.PLUSEQ, JetTokens.PLUS); assignmentOperationCounterparts.put(JetTokens.MINUSEQ, JetTokens.MINUS); } private final BindingTrace trace; private final JetSemanticServices semanticServices; private final TypeResolver typeResolver; private final ClassDescriptorResolver classDescriptorResolver; public JetTypeInferrer(BindingTrace trace, JetSemanticServices semanticServices) { this.trace = trace; this.semanticServices = semanticServices; this.typeResolver = new TypeResolver(trace, semanticServices); this.classDescriptorResolver = semanticServices.getClassDescriptorResolver(trace); } @NotNull public JetType safeGetType(@NotNull final JetScope scope, @NotNull JetExpression expression, final boolean preferBlock) { JetType type = getType(scope, expression, preferBlock); if (type != null) { return type; } return ErrorType.createErrorType("Type for " + expression.getText()); } @Nullable public JetType getType(@NotNull final JetScope scope, @NotNull JetExpression expression, final boolean preferBlock) { TypeInferrerVisitor visitor = new TypeInferrerVisitor(scope, preferBlock); expression.accept(visitor); JetType result = visitor.getResult(); if (result != null) { trace.recordExpressionType(expression, result); } return result; } @NotNull private JetExpression deparenthesize(@NotNull JetExpression expression) { while (expression instanceof JetParenthesizedExpression) { expression = ((JetParenthesizedExpression) expression).getExpression(); } return expression; } @Nullable private FunctionDescriptor lookupFunction(JetScope scope, JetReferenceExpression reference, String name, JetType receiverType, List argumentTypes, boolean reportUnresolved) { OverloadDomain overloadDomain = semanticServices.getOverloadResolver().getOverloadDomain(receiverType, scope, name); overloadDomain = wrapForTracing(overloadDomain, reference, reportUnresolved); return overloadDomain.getFunctionDescriptorForPositionedArguments(Collections.emptyList(), argumentTypes); } @Nullable private List getTypes(JetScope scope, List indexExpressions) { List argumentTypes = new ArrayList(); for (JetExpression indexExpression : indexExpressions) { JetType type = getType(scope, indexExpression, false); if (type == null) { return null; } argumentTypes.add(type); } return argumentTypes; } private OverloadDomain getOverloadDomain(final JetScope scope, JetExpression calleeExpression) { final OverloadDomain[] result = new OverloadDomain[1]; final JetSimpleNameExpression[] reference = new JetSimpleNameExpression[1]; calleeExpression.accept(new JetVisitor() { @Override public void visitHashQualifiedExpression(JetHashQualifiedExpression expression) { // a#b -- create a domain for all overloads of b in a throw new UnsupportedOperationException(); // TODO } @Override public void visitPredicateExpression(JetPredicateExpression expression) { // overload lookup for checking, but the type is receiver's type + nullable throw new UnsupportedOperationException(); // TODO } @Override public void visitQualifiedExpression(JetQualifiedExpression expression) { // . or ?. JetType receiverType = getType(scope, expression.getReceiverExpression(), false); checkNullSafety(receiverType, expression); JetExpression selectorExpression = expression.getSelectorExpression(); if (selectorExpression instanceof JetSimpleNameExpression) { JetSimpleNameExpression referenceExpression = (JetSimpleNameExpression) selectorExpression; if (receiverType != null) { result[0] = semanticServices.getOverloadResolver().getOverloadDomain(receiverType, scope, referenceExpression.getReferencedName()); reference[0] = referenceExpression; } } else { throw new UnsupportedOperationException(); // TODO } } @Override public void visitSimpleNameExpression(JetSimpleNameExpression expression) { // a -- create a hierarchical lookup domain for this.a result[0] = semanticServices.getOverloadResolver().getOverloadDomain(null, scope, expression.getReferencedName()); reference[0] = expression; } @Override public void visitExpression(JetExpression expression) { // create a dummy domain for the type of e throw new UnsupportedOperationException(expression.getText()); // TODO } @Override public void visitJetElement(JetElement elem) { throw new IllegalArgumentException("Unsupported element: " + elem); } }); return wrapForTracing(result[0], reference[0], true); } private void checkNullSafety(JetType receiverType, JetQualifiedExpression expression) { if (receiverType != null) { boolean namespaceType = receiverType instanceof NamespaceType; boolean nullable = !namespaceType && receiverType.isNullable(); if (nullable && expression.getOperationSign() == JetTokens.DOT) { semanticServices.getErrorHandler().genericError(expression.getOperationTokenNode(), "Only safe calls (?.) are allowed on a nullable receiver of type " + receiverType); } else if (!nullable && expression.getOperationSign() == JetTokens.SAFE_ACCESS) { if (namespaceType) { semanticServices.getErrorHandler().genericError(expression.getOperationTokenNode(), "Safe calls are not allowed on namespaces"); } else { semanticServices.getErrorHandler().genericWarning(expression.getOperationTokenNode(), "Unnecessary safe call on a non-null receiver of type " + receiverType); } } } } private OverloadDomain wrapForTracing(final OverloadDomain overloadDomain, @NotNull final JetReferenceExpression referenceExpression, final boolean reportUnresolved) { if (overloadDomain == null) return OverloadDomain.EMPTY; return new OverloadDomain() { @Override public FunctionDescriptor getFunctionDescriptorForNamedArguments(@NotNull List typeArguments, @NotNull Map valueArgumentTypes, @Nullable JetType functionLiteralArgumentType) { FunctionDescriptor descriptor = overloadDomain.getFunctionDescriptorForNamedArguments(typeArguments, valueArgumentTypes, functionLiteralArgumentType); if (descriptor != null) { trace.recordReferenceResolution(referenceExpression, descriptor); } else { if (reportUnresolved) { semanticServices.getErrorHandler().unresolvedReference(referenceExpression); } } return descriptor; } @Override public FunctionDescriptor getFunctionDescriptorForPositionedArguments(@NotNull List typeArguments, @NotNull List positionedValueArgumentTypes) { FunctionDescriptor descriptor = overloadDomain.getFunctionDescriptorForPositionedArguments(typeArguments, positionedValueArgumentTypes); if (descriptor != null) { trace.recordReferenceResolution(referenceExpression, descriptor); } else { if (reportUnresolved) { semanticServices.getErrorHandler().unresolvedReference(referenceExpression); } } return descriptor; } }; } private JetType getBlockReturnedType(@NotNull JetScope outerScope, List block) { if (block.isEmpty()) { return JetStandardClasses.getUnitType(); } else { DeclarationDescriptor containingDescriptor = outerScope.getContainingDeclaration(); WritableScope scope = semanticServices.createWritableScope(outerScope, containingDescriptor); return getBlockReturnedTypeWithWritableScope(scope, block); } } private JetType getBlockReturnedTypeWithWritableScope(@NotNull WritableScope scope, @NotNull List block) { assert !block.isEmpty(); TypeInferrerVisitorWithWritableScope blockLevelVisitor = new TypeInferrerVisitorWithWritableScope(scope, true); JetType result = null; for (JetElement statement : block) { statement.accept(blockLevelVisitor); result = blockLevelVisitor.getResult(); if (result != null) { trace.recordExpressionType((JetExpression) statement, result); } blockLevelVisitor.resetResult(); // TODO : maybe it's better to recreate the visitors with the same scope? } return result; } private void collectAllReturnTypes(JetWhenExpression whenExpression, JetScope scope, List result) { for (JetWhenEntry entry : whenExpression.getEntries()) { JetWhenExpression subWhen = entry.getSubWhen(); if (subWhen != null) { collectAllReturnTypes(subWhen, scope, result); } else { JetExpression resultExpression = entry.getExpression(); if (resultExpression != null) { result.add(getType(scope, resultExpression, true)); } } } } private class TypeInferrerVisitor extends JetVisitor { private final JetScope scope; protected JetType result; private final boolean preferBlock; public TypeInferrerVisitor(JetScope scope, boolean preferBlock) { this.scope = scope; this.preferBlock = preferBlock; } public JetType getResult() { return result; } @Override public void visitSimpleNameExpression(JetSimpleNameExpression expression) { // TODO : other members // TODO : type substitutions??? String referencedName = expression.getReferencedName(); if (referencedName != null) { PropertyDescriptor property = scope.getProperty(referencedName); if (property != null) { trace.recordReferenceResolution(expression, property); result = property.getType(); return; } else { NamespaceDescriptor namespace = scope.getNamespace(referencedName); if (namespace != null) { trace.recordReferenceResolution(expression, namespace); result = namespace.getNamespaceType(); return; } } semanticServices.getErrorHandler().unresolvedReference(expression); } } @Override public void visitFunctionLiteralExpression(JetFunctionLiteralExpression expression) { if (preferBlock && !expression.hasParameterSpecification()) { result = getBlockReturnedType(scope, expression.getBody()); return; } FunctionDescriptorImpl functionDescriptor = new FunctionDescriptorImpl(scope.getContainingDeclaration(), Collections.emptyList(), ""); JetTypeReference returnTypeRef = expression.getReturnTypeRef(); JetTypeReference receiverTypeRef = expression.getReceiverTypeRef(); final JetType receiverType; if (receiverTypeRef != null) { receiverType = typeResolver.resolveType(scope, receiverTypeRef); } else { receiverType = scope.getThisType(); } List body = expression.getBody(); final Map parameterDescriptors = new HashMap(); List parameterTypes = new ArrayList(); for (JetParameter parameter : expression.getParameters()) { JetTypeReference typeReference = parameter.getTypeReference(); if (typeReference == null) { throw new UnsupportedOperationException("Type inference for parameters is not implemented yet"); } PropertyDescriptor propertyDescriptor = classDescriptorResolver.resolvePropertyDescriptor(functionDescriptor, scope, parameter); parameterDescriptors.put(parameter.getName(), propertyDescriptor); parameterTypes.add(propertyDescriptor.getType()); } JetType returnType; if (returnTypeRef != null) { returnType = typeResolver.resolveType(scope, returnTypeRef); } else { WritableScope writableScope = semanticServices.createWritableScope(scope, functionDescriptor); for (PropertyDescriptor propertyDescriptor : parameterDescriptors.values()) { writableScope.addPropertyDescriptor(propertyDescriptor); } writableScope.setThisType(receiverType); returnType = getBlockReturnedType(writableScope, body); } result = JetStandardClasses.getFunctionType(null, receiverTypeRef == null ? null : receiverType, parameterTypes, returnType); } @Override public void visitParenthesizedExpression(JetParenthesizedExpression expression) { result = getType(scope, expression.getExpression(), false); } @Override public void visitConstantExpression(JetConstantExpression expression) { IElementType elementType = expression.getNode().getElementType(); JetStandardLibrary standardLibrary = semanticServices.getStandardLibrary(); if (elementType == JetNodeTypes.INTEGER_CONSTANT) { result = standardLibrary.getIntType(); } else if (elementType == JetNodeTypes.LONG_CONSTANT) { result = standardLibrary.getLongType(); } else if (elementType == JetNodeTypes.FLOAT_CONSTANT) { String text = expression.getText(); assert text.length() > 0; char lastChar = text.charAt(text.length() - 1); if (lastChar == 'f' || lastChar == 'F') { result = standardLibrary.getFloatType(); } else { result = standardLibrary.getDoubleType(); } } else if (elementType == JetNodeTypes.BOOLEAN_CONSTANT) { result = standardLibrary.getBooleanType(); } else if (elementType == JetNodeTypes.CHARACTER_CONSTANT) { result = standardLibrary.getCharType(); } else if (elementType == JetNodeTypes.STRING_CONSTANT) { result = standardLibrary.getStringType(); } else if (elementType == JetNodeTypes.NULL) { result = JetStandardClasses.getNullableNothingType(); } else { throw new IllegalArgumentException("Unsupported constant: " + expression); } } @Override public void visitThrowExpression(JetThrowExpression expression) { result = JetStandardClasses.getNothingType(); } @Override public void visitReturnExpression(JetReturnExpression expression) { JetExpression returnedExpression = expression.getReturnedExpression(); if (returnedExpression != null) { getType(scope, returnedExpression, false); } result = JetStandardClasses.getNothingType(); } @Override public void visitBreakExpression(JetBreakExpression expression) { result = JetStandardClasses.getNothingType(); } @Override public void visitContinueExpression(JetContinueExpression expression) { result = JetStandardClasses.getNothingType(); } @Override public void visitTypeofExpression(JetTypeofExpression expression) { throw new UnsupportedOperationException("Return some reflection interface"); // TODO } @Override public void visitBinaryWithTypeRHSExpression(JetBinaryExpressionWithTypeRHS expression) { IElementType operationType = expression.getOperationSign().getReferencedNameElementType(); JetType actualType = getType(scope, expression.getLeft(), false); JetTypeReference right = expression.getRight(); if (right != null) { JetType targetType = typeResolver.resolveType(scope, right); if (operationType == JetTokens.COLON) { if (actualType != null && !semanticServices.getTypeChecker().isSubtypeOf(actualType, targetType)) { semanticServices.getErrorHandler().typeMismatch(expression.getLeft(), targetType, actualType); } } else if (operationType == JetTokens.AS_KEYWORD) { // TODO : Check for cast impossibility } else { semanticServices.getErrorHandler().genericError(expression.getOperationSign().getNode(), "Unsupported binary operation"); } result = targetType; } } @Override public void visitTupleExpression(JetTupleExpression expression) { List entries = expression.getEntries(); List types = new ArrayList(); for (JetExpression entry : entries) { types.add(getType(scope, entry, false)); } // TODO : labels result = JetStandardClasses.getTupleType(types); } @Override public void visitThisExpression(JetThisExpression expression) { // TODO : qualified this, e.g. Foo.this JetType thisType = scope.getThisType(); JetTypeReference superTypeQualifier = expression.getSuperTypeQualifier(); if (superTypeQualifier != null) { // This cast must be safe (assuming the PSI doesn't contain errors) JetUserType typeElement = (JetUserType) superTypeQualifier.getTypeElement(); ClassDescriptor superclass = typeResolver.resolveClass(scope, typeElement); Collection supertypes = thisType.getConstructor().getSupertypes(); Map substitutionContext = TypeSubstitutor.INSTANCE.buildSubstitutionContext(thisType); for (JetType declaredSupertype : supertypes) { if (declaredSupertype.getConstructor().equals(superclass.getTypeConstructor())) { result = TypeSubstitutor.INSTANCE.substitute(substitutionContext, declaredSupertype, Variance.INVARIANT); break; } } assert result != null; } else { result = thisType; } } @Override public void visitBlockExpression(JetBlockExpression expression) { result = getBlockReturnedType(scope, expression.getStatements()); } @Override public void visitWhenExpression(JetWhenExpression expression) { // TODO :change scope according to the bound value in the when header List expressions = new ArrayList(); collectAllReturnTypes(expression, scope, expressions); result = semanticServices.getTypeChecker().commonSupertype(expressions); } @Override public void visitTryExpression(JetTryExpression expression) { JetExpression tryBlock = expression.getTryBlock(); List catchClauses = expression.getCatchClauses(); JetFinallySection finallyBlock = expression.getFinallyBlock(); List types = new ArrayList(); if (finallyBlock == null) { for (JetCatchClause catchClause : catchClauses) { // TODO: change scope here types.add(getType(scope, catchClause.getCatchBody(), true)); } } else { types.add(getType(scope, finallyBlock.getFinalExpression(), true)); } types.add(getType(scope, tryBlock, true)); result = semanticServices.getTypeChecker().commonSupertype(types); } @Override public void visitIfExpression(JetIfExpression expression) { checkCondition(scope, expression.getCondition()); // TODO : change types according to is and null checks JetExpression elseBranch = expression.getElse(); JetExpression thenBranch = expression.getThen(); JetType thenType = null; if (thenBranch != null) { thenType = getType(scope, thenBranch, true); } if (elseBranch != null) { JetType elseType = getType(scope, elseBranch, true); if (thenType == null) { result = elseType; } else if (elseType == null) { result = thenType; } else { result = semanticServices.getTypeChecker().commonSupertype(Arrays.asList(thenType, elseType)); } } else { result = JetStandardClasses.getUnitType(); } } private void checkCondition(@NotNull JetScope scope, @Nullable JetExpression condition) { if (condition != null) { JetType conditionType = getType(scope, condition, false); if (conditionType != null && !isBoolean(conditionType)) { semanticServices.getErrorHandler().genericError(condition.getNode(), "Condition must be of type Boolean, but was of type " + conditionType); } } } @Override public void visitWhileExpression(JetWhileExpression expression) { checkCondition(scope, expression.getCondition()); JetExpression body = expression.getBody(); if (body != null) { getType(scope, body, true); } result = JetStandardClasses.getUnitType(); } @Override public void visitDoWhileExpression(JetDoWhileExpression expression) { JetExpression body = expression.getBody(); JetScope conditionScope = scope; if (body instanceof JetFunctionLiteralExpression) { JetFunctionLiteralExpression function = (JetFunctionLiteralExpression) body; if (!function.hasParameterSpecification()) { WritableScope writableScope = semanticServices.createWritableScope(scope, scope.getContainingDeclaration()); conditionScope = writableScope; getBlockReturnedTypeWithWritableScope(writableScope, function.getBody()); } else { getType(scope, body, true); } } else if (body != null) { WritableScope writableScope = semanticServices.createWritableScope(scope, scope.getContainingDeclaration()); conditionScope = writableScope; getBlockReturnedTypeWithWritableScope(writableScope, Collections.singletonList(body)); } checkCondition(conditionScope, expression.getCondition()); result = JetStandardClasses.getUnitType(); } @Override public void visitForExpression(JetForExpression expression) { JetParameter loopParameter = expression.getLoopParameter(); JetExpression loopRange = expression.getLoopRange(); JetType loopRangeType = getType(scope, loopRange, false); JetType expectedParameterType = null; if (loopRangeType != null) { if (!semanticServices.getTypeChecker().isSubtypeOf(loopRangeType, semanticServices.getStandardLibrary().getIterableType(JetStandardClasses.getNullableAnyType()))) { semanticServices.getErrorHandler().genericError(loopRange.getNode(), "Expecting an Iterable, but found " + loopRangeType); } else { TypeProjection typeProjection = loopRangeType.getArguments().get(0); if (!typeProjection.getProjectionKind().allowsOutPosition()) { expectedParameterType = JetStandardClasses.getDefaultBound(); } else { expectedParameterType = typeProjection.getType(); } } } WritableScope loopScope = semanticServices.createWritableScope(scope, scope.getContainingDeclaration()); JetTypeReference typeReference = loopParameter.getTypeReference(); PropertyDescriptor propertyDescriptor; if (typeReference != null) { propertyDescriptor = semanticServices.getClassDescriptorResolver(trace).resolvePropertyDescriptor(scope.getContainingDeclaration(), scope, loopParameter); JetType actualParameterType = propertyDescriptor.getType(); if (expectedParameterType != null && !semanticServices.getTypeChecker().isSubtypeOf(expectedParameterType, actualParameterType)) { semanticServices.getErrorHandler().genericError(typeReference.getNode(), "The loop iterates over values of type " + expectedParameterType + " but the parameter is declared to be " + actualParameterType); } } else { if (expectedParameterType == null) { expectedParameterType = ErrorType.createErrorType("Error"); } propertyDescriptor = semanticServices.getClassDescriptorResolver(trace).resolvePropertyDescriptor(scope.getContainingDeclaration(), loopParameter, expectedParameterType); } loopScope.addPropertyDescriptor(propertyDescriptor); trace.recordDeclarationResolution(loopParameter, propertyDescriptor); JetExpression body = expression.getBody(); if (body != null) { getType(loopScope, body, true); // TODO } result = JetStandardClasses.getUnitType(); } @Override public void visitNewExpression(JetNewExpression expression) { // TODO : type argument inference JetTypeReference typeReference = expression.getTypeReference(); if (typeReference != null) { JetTypeElement typeElement = typeReference.getTypeElement(); if (typeElement instanceof JetUserType) { JetUserType userType = (JetUserType) typeElement; // TODO : to infer constructor parameters, one will need to // 1) resolve a _class_ from the typeReference // 2) rely on the overload domain of constructors of this class to infer type arguments // For now we assume that the type arguments are provided, and thus the typeReference can be // resolved into a valid type JetType receiverType = typeResolver.resolveType(scope, typeReference); DeclarationDescriptor declarationDescriptor = receiverType.getConstructor().getDeclarationDescriptor(); if (declarationDescriptor instanceof ClassDescriptor) { ClassDescriptor classDescriptor = (ClassDescriptor) declarationDescriptor; JetSimpleNameExpression referenceExpression = userType.getReferenceExpression(); if (referenceExpression != null) { FunctionGroup constructors = classDescriptor.getConstructors(receiverType.getArguments()); OverloadDomain constructorsOverloadDomain = semanticServices.getOverloadResolver().getOverloadDomain(constructors); result = resolveOverloads( scope, wrapForTracing(constructorsOverloadDomain, referenceExpression, true), Collections.emptyList(), expression.getArguments(), expression.getFunctionLiteralArguments()); } } else { semanticServices.getErrorHandler().genericError(expression.getNode(), "Calling a constructor is only supported for ordinary classes"); // TODO : review the message } } else { semanticServices.getErrorHandler().genericError(typeElement.getNode(), "Calling a constructor is only supported for ordinary classes"); // TODO : Better message } } } @Override public void visitHashQualifiedExpression(JetHashQualifiedExpression expression) { throw new UnsupportedOperationException(); // TODO } @Override public void visitQualifiedExpression(JetQualifiedExpression expression) { // TODO : functions JetExpression selectorExpression = expression.getSelectorExpression(); JetExpression receiverExpression = expression.getReceiverExpression(); JetType receiverType = getType(scope, receiverExpression, false); if (receiverType != null) { checkNullSafety(receiverType, expression); JetType selectorReturnType = getSelectorReturnType(receiverType, selectorExpression); if (expression.getOperationSign() == JetTokens.QUEST) { if (selectorReturnType != null && !isBoolean(selectorReturnType)) { // TODO : more comprehensible error message semanticServices.getErrorHandler().typeMismatch(selectorExpression, semanticServices.getStandardLibrary().getBooleanType(), selectorReturnType); } result = TypeUtils.makeNullable(receiverType); } else { result = selectorReturnType; } } } private JetType getSelectorReturnType(JetType receiverType, JetExpression selectorExpression) { JetScope compositeScope = new ScopeWithReceiver(scope, receiverType); if (selectorExpression instanceof JetCallExpression) { JetCallExpression callExpression = (JetCallExpression) selectorExpression; OverloadDomain overloadDomain = getOverloadDomain(compositeScope, callExpression.getCalleeExpression()); return resolveOverloads(scope, callExpression, overloadDomain); } else if (selectorExpression instanceof JetSimpleNameExpression) { return getType(compositeScope, selectorExpression, false); } else if (selectorExpression != null) { // TODO : not a simple name -> resolve in scope, expect property type or a function type throw new UnsupportedOperationException(); } return receiverType; } @Override public void visitCallExpression(JetCallExpression expression) { JetExpression calleeExpression = expression.getCalleeExpression(); OverloadDomain overloadDomain = getOverloadDomain(scope, calleeExpression); result = resolveOverloads(scope, expression, overloadDomain); } @Nullable private JetType resolveOverloads(JetScope scope, JetCallExpression expression, OverloadDomain overloadDomain) { List typeArguments = expression.getTypeArguments(); List valueArguments = expression.getValueArguments(); List functionLiteralArguments = expression.getFunctionLiteralArguments(); return resolveOverloads(scope, overloadDomain, typeArguments, valueArguments, functionLiteralArguments); } @Nullable private JetType resolveOverloads( @NotNull JetScope scope, @NotNull OverloadDomain overloadDomain, @NotNull List typeArguments, @NotNull List valueArguments, @NotNull List functionLiteralArguments) { // 1) ends with a name -> (scope, name) to look up // 2) ends with something else -> just check types for (JetTypeProjection typeArgument : typeArguments) { if (typeArgument.getProjectionKind() != JetProjectionKind.NONE) { semanticServices.getErrorHandler().genericError(typeArgument.getNode(), "Projections are not allowed on type parameters for methods"); // TODO : better positioning } } boolean someNamed = false; for (JetArgument argument : valueArguments) { if (argument.isNamed()) { someNamed = true; break; } } // JetExpression functionLiteralArgument = functionLiteralArguments.isEmpty() ? null : functionLiteralArguments.get(0); // TODO : must be a check assert functionLiteralArguments.size() <= 1; if (someNamed) { // TODO : check that all are named throw new UnsupportedOperationException(); // TODO // result = overloadDomain.getFunctionDescriptorForNamedArguments(typeArguments, valueArguments, functionLiteralArgument); } else { List types = new ArrayList(); for (JetTypeProjection projection : typeArguments) { // TODO : check that there's no projection types.add(typeResolver.resolveType(scope, projection.getTypeReference())); } List positionedValueArguments = new ArrayList(); for (JetArgument argument : valueArguments) { positionedValueArguments.add(argument.getArgumentExpression()); } positionedValueArguments.addAll(functionLiteralArguments); List valueArgumentTypes = new ArrayList(); for (JetExpression valueArgument : positionedValueArguments) { valueArgumentTypes.add(safeGetType(scope, valueArgument, false)); } FunctionDescriptor functionDescriptor = overloadDomain.getFunctionDescriptorForPositionedArguments(types, valueArgumentTypes); if (functionDescriptor != null) { return functionDescriptor.getUnsubstitutedReturnType(); } } return null; } @Override public void visitIsExpression(JetIsExpression expression) { // TODO : patterns and everything System.out.println("Pattern matching is not supported yet."); result = semanticServices.getStandardLibrary().getBooleanType(); } @Override public void visitUnaryExpression(JetUnaryExpression expression) { JetSimpleNameExpression operationSign = expression.getOperationSign(); IElementType operationType = operationSign.getReferencedNameElementType(); String name = unaryOperationNames.get(operationType); if (name == null) { semanticServices.getErrorHandler().genericError(operationSign.getNode(), "Unknown unary operation"); } else { JetType receiverType = getType(scope, expression.getBaseExpression(), false); if (receiverType != null) { FunctionDescriptor functionDescriptor = lookupFunction(scope, expression.getOperationSign(), name, receiverType, Collections.emptyList(), true); if (functionDescriptor != null) { JetType returnType = functionDescriptor.getUnsubstitutedReturnType(); if (operationType == JetTokens.PLUSPLUS || operationType == JetTokens.MINUSMINUS) { if (!semanticServices.getTypeChecker().isSubtypeOf(returnType, receiverType)) { semanticServices.getErrorHandler().genericError(operationSign.getNode(), name + " must return " + receiverType + " but returns " + returnType); } // TODO : Maybe returnType? result = receiverType; } else { result = returnType; } } } } } @Override public void visitBinaryExpression(JetBinaryExpression expression) { JetSimpleNameExpression operationSign = expression.getOperationReference(); JetExpression left = expression.getLeft(); JetExpression right = expression.getRight(); IElementType operationType = operationSign.getReferencedNameElementType(); if (operationType == JetTokens.IDENTIFIER) { String referencedName = operationSign.getReferencedName(); if (referencedName != null) { result = getTypeForBinaryCall(expression, referencedName, scope, true); } } else if (binaryOperationNames.containsKey(operationType)) { result = getTypeForBinaryCall(expression, binaryOperationNames.get(operationType), scope, true); } else if (operationType == JetTokens.EQ) { visitAssignment(expression); } else if (assignmentOperationNames.containsKey(operationType)) { visitAssignmentOperation(expression); } else if (comparisonOperations.contains(operationType)) { JetType compareToReturnType = getTypeForBinaryCall(expression, "compareTo", scope, true); if (compareToReturnType != null) { TypeConstructor constructor = compareToReturnType.getConstructor(); JetStandardLibrary standardLibrary = semanticServices.getStandardLibrary(); TypeConstructor intTypeConstructor = standardLibrary.getInt().getTypeConstructor(); if (constructor.equals(intTypeConstructor)) { result = standardLibrary.getBooleanType(); } else { semanticServices.getErrorHandler().genericError(operationSign.getNode(), "compareTo must return Int, but returns " + compareToReturnType); } } } else if (equalsOperations.contains(operationType)) { String name = "equals"; JetType equalsType = getTypeForBinaryCall(expression, name, scope, true); assureBooleanResult(operationSign, name, equalsType); } else if (inOperations.contains(operationType)) { if (right == null) { result = ErrorType.createErrorType("No right argument"); // TODO return; } String name = "contains"; JetType containsType = getTypeForBinaryCall(scope, right, expression.getOperationReference(), expression.getLeft(), name, true); result = assureBooleanResult(operationSign, name, containsType); } else if (operationType == JetTokens.EQEQEQ || operationType == JetTokens.EXCLEQEQEQ) { JetType leftType = getType(scope, left, false); JetType rightType = right == null ? null : getType(scope, right, false); // TODO : Check comparison pointlessness result = semanticServices.getStandardLibrary().getBooleanType(); } else if (operationType == JetTokens.ANDAND || operationType == JetTokens.OROR) { JetType leftType = getType(scope, left, false); JetType rightType = right == null ? null : getType(scope, right, false); if (leftType != null && !isBoolean(leftType)) { semanticServices.getErrorHandler().typeMismatch(left, semanticServices.getStandardLibrary().getBooleanType(), leftType); } if (rightType != null && !isBoolean(rightType)) { semanticServices.getErrorHandler().typeMismatch(left, semanticServices.getStandardLibrary().getBooleanType(), rightType); semanticServices.getErrorHandler().typeMismatch(right, semanticServices.getStandardLibrary().getBooleanType(), rightType); } result = semanticServices.getStandardLibrary().getBooleanType(); } else if (operationType == JetTokens.ELVIS) { JetType leftType = getType(scope, left, false); JetType rightType = right == null ? null : getType(scope, right, false); if (leftType != null) { if (!leftType.isNullable()) { semanticServices.getErrorHandler().genericWarning(left.getNode(), "Elvis operator (?:) is always returns the left operand of non-nullable type " + leftType); } if (rightType != null) { result = TypeUtils.makeNullableAsSpecified(semanticServices.getTypeChecker().commonSupertype(leftType, rightType), rightType.isNullable()); } } } else { semanticServices.getErrorHandler().genericError(operationSign.getNode(), "Unknown operation"); } } protected void visitAssignmentOperation(JetBinaryExpression expression) { assignmentIsNotAnExpressionError(expression); } protected void visitAssignment(JetBinaryExpression expression) { assignmentIsNotAnExpressionError(expression); } private void assignmentIsNotAnExpressionError(JetBinaryExpression expression) { semanticServices.getErrorHandler().genericError(expression.getNode(), "Assignments are not expressions, and only expressions are allowed in this context"); } private JetType assureBooleanResult(JetSimpleNameExpression operationSign, String name, JetType resultType) { if (resultType != null) { // TODO : Relax? if (!isBoolean(resultType)) { semanticServices.getErrorHandler().genericError(operationSign.getNode(), "'" + name + "' must return Boolean but returns " + resultType); return null; } else { return resultType; } } return resultType; } private boolean isBoolean(@NotNull JetType type) { TypeConstructor booleanTypeConstructor = semanticServices.getStandardLibrary().getBoolean().getTypeConstructor(); return type.getConstructor().equals(booleanTypeConstructor) || ErrorType.isErrorType(type); } @Override public void visitArrayAccessExpression(JetArrayAccessExpression expression) { JetExpression arrayExpression = expression.getArrayExpression(); JetType receiverType = getType(scope, arrayExpression, false); List indexExpressions = expression.getIndexExpressions(); List argumentTypes = getTypes(scope, indexExpressions); if (argumentTypes == null) return; FunctionDescriptor functionDescriptor = lookupFunction(scope, expression, "get", receiverType, argumentTypes, true); if (functionDescriptor != null) { result = functionDescriptor.getUnsubstitutedReturnType(); } } @Nullable protected JetType getTypeForBinaryCall(JetBinaryExpression expression, @NotNull String name, JetScope scope, boolean reportUnresolved) { JetExpression left = expression.getLeft(); JetExpression right = expression.getRight(); if (right == null) { return null; } JetSimpleNameExpression operationSign = expression.getOperationReference(); return getTypeForBinaryCall(scope, left, operationSign, right, name, reportUnresolved); } @Nullable private JetType getTypeForBinaryCall(JetScope scope, JetExpression left, JetSimpleNameExpression operationSign, @NotNull JetExpression right, String name, boolean reportUnresolved) { JetType leftType = safeGetType(scope, left, false); JetType rightType = safeGetType(scope, right, false); if (ErrorType.isErrorType(leftType)) { return null; } FunctionDescriptor functionDescriptor = lookupFunction(scope, operationSign, name, leftType, Collections.singletonList(rightType), reportUnresolved); if (functionDescriptor != null) { return functionDescriptor.getUnsubstitutedReturnType(); } return null; } @Override public void visitDeclaration(JetDeclaration dcl) { semanticServices.getErrorHandler().genericError(dcl.getNode(), "Declarations are not allowed in this position"); } @Override public void visitJetElement(JetElement elem) { semanticServices.getErrorHandler().genericError(elem.getNode(), "Unsupported element: " + elem + " " + elem.getClass().getCanonicalName()); } } private class TypeInferrerVisitorWithWritableScope extends TypeInferrerVisitor { private final WritableScope scope; public TypeInferrerVisitorWithWritableScope(@NotNull WritableScope scope, boolean preferBlock) { super(scope, preferBlock); this.scope = scope; } public void resetResult() { this.result = null; } @Override public void visitProperty(JetProperty property) { PropertyDescriptor propertyDescriptor = classDescriptorResolver.resolvePropertyDescriptor(scope.getContainingDeclaration(), scope, property); scope.addPropertyDescriptor(propertyDescriptor); trace.recordDeclarationResolution(property, propertyDescriptor); } @Override public void visitFunction(JetFunction function) { super.visitFunction(function); // TODO } @Override public void visitClass(JetClass klass) { super.visitClass(klass); // TODO } @Override public void visitExtension(JetExtension extension) { super.visitExtension(extension); // TODO } @Override public void visitTypedef(JetTypedef typedef) { super.visitTypedef(typedef); // TODO } @Override public void visitDeclaration(JetDeclaration dcl) { visitJetElement(dcl); } @Override protected void visitAssignmentOperation(JetBinaryExpression expression) { IElementType operationType = expression.getOperationReference().getReferencedNameElementType(); String name = assignmentOperationNames.get(operationType); JetType assignmentOperationType = getTypeForBinaryCall(expression, name, scope, false); if (assignmentOperationType == null) { String counterpartName = binaryOperationNames.get(assignmentOperationCounterparts.get(operationType)); getTypeForBinaryCall(expression, counterpartName, scope, true); } result = null; // not an expression } @Override protected void visitAssignment(JetBinaryExpression expression) { JetExpression left = expression.getLeft(); JetExpression deparenthesized = deparenthesize(left); JetExpression right = expression.getRight(); if (deparenthesized instanceof JetArrayAccessExpression) { JetArrayAccessExpression arrayAccessExpression = (JetArrayAccessExpression) deparenthesized; resolveArrayAccessToLValue(arrayAccessExpression, right, expression.getOperationReference()); } else { JetType leftType = getType(scope, left, false); if (right != null) { JetType rightType = getType(scope, right, false); if (rightType != null && leftType != null && !semanticServices.getTypeChecker().isConvertibleTo(rightType, leftType)) { semanticServices.getErrorHandler().typeMismatch(right, leftType, rightType); } } } result = null; // This is not an expression } private void resolveArrayAccessToLValue(JetArrayAccessExpression arrayAccessExpression, JetExpression rightHandSide, JetSimpleNameExpression operationSign) { List argumentTypes = getTypes(scope, arrayAccessExpression.getIndexExpressions()); if (argumentTypes == null) return; JetType rhsType = getType(scope, rightHandSide, false); if (rhsType == null) return; argumentTypes.add(rhsType); JetType receiverType = getType(scope, arrayAccessExpression.getArrayExpression(), false); if (receiverType == null) return; // TODO : nasty hack: effort is duplicated lookupFunction(scope, arrayAccessExpression, "set", receiverType, argumentTypes, true); FunctionDescriptor functionDescriptor = lookupFunction(scope, operationSign, "set", receiverType, argumentTypes, true); if (functionDescriptor != null) { result = functionDescriptor.getUnsubstitutedReturnType(); } } @Override public void visitJetElement(JetElement elem) { semanticServices.getErrorHandler().genericError(elem.getNode(), "Unsupported element in a block: " + elem + " " + elem.getClass().getCanonicalName()); } } }