@Override
public KotlinTypeInfo visitTryExpression(
@NotNull KtTryExpression expression, ExpressionTypingContext typingContext) {
ExpressionTypingContext context = typingContext.replaceContextDependency(INDEPENDENT);
KtExpression tryBlock = expression.getTryBlock();
List<KtCatchClause> catchClauses = expression.getCatchClauses();
KtFinallySection finallyBlock = expression.getFinallyBlock();
List<KotlinType> types = new ArrayList<KotlinType>();
for (KtCatchClause catchClause : catchClauses) {
KtParameter catchParameter = catchClause.getCatchParameter();
KtExpression catchBody = catchClause.getCatchBody();
if (catchParameter != null) {
components.identifierChecker.checkDeclaration(catchParameter, context.trace);
ModifiersChecker.ModifiersCheckingProcedure modifiersChecking =
components.modifiersChecker.withTrace(context.trace);
modifiersChecking.checkParameterHasNoValOrVar(
catchParameter, VAL_OR_VAR_ON_CATCH_PARAMETER);
ModifierCheckerCore.INSTANCE$.check(catchParameter, context.trace, null);
VariableDescriptor variableDescriptor =
components.descriptorResolver.resolveLocalVariableDescriptor(
context.scope, catchParameter, context.trace);
KotlinType throwableType = components.builtIns.getThrowable().getDefaultType();
components.dataFlowAnalyzer.checkType(
variableDescriptor.getType(),
catchParameter,
context.replaceExpectedType(throwableType));
if (catchBody != null) {
LexicalWritableScope catchScope = newWritableScopeImpl(context, "Catch scope");
catchScope.addVariableDescriptor(variableDescriptor);
KotlinType type =
facade.getTypeInfo(catchBody, context.replaceScope(catchScope)).getType();
if (type != null) {
types.add(type);
}
}
}
}
KotlinTypeInfo result = TypeInfoFactoryKt.noTypeInfo(context);
if (finallyBlock != null) {
result =
facade.getTypeInfo(
finallyBlock.getFinalExpression(), context.replaceExpectedType(NO_EXPECTED_TYPE));
}
KotlinType type = facade.getTypeInfo(tryBlock, context).getType();
if (type != null) {
types.add(type);
}
if (types.isEmpty()) {
return result.clearType();
} else {
return result.replaceType(CommonSupertypes.commonSupertype(types));
}
}
@Override
public KotlinTypeInfo visitThrowExpression(
@NotNull KtThrowExpression expression, ExpressionTypingContext context) {
KtExpression thrownExpression = expression.getThrownExpression();
if (thrownExpression != null) {
KotlinType throwableType = components.builtIns.getThrowable().getDefaultType();
facade.getTypeInfo(
thrownExpression,
context
.replaceExpectedType(throwableType)
.replaceScope(context.scope)
.replaceContextDependency(INDEPENDENT));
}
return components.dataFlowAnalyzer.createCheckedTypeInfo(
components.builtIns.getNothingType(), context, expression);
}
@NotNull
private DataFlowInfo checkCondition(
@NotNull LexicalScope scope,
@Nullable KtExpression condition,
ExpressionTypingContext context) {
if (condition != null) {
KotlinTypeInfo typeInfo =
facade.getTypeInfo(
condition,
context
.replaceScope(scope)
.replaceExpectedType(components.builtIns.getBooleanType())
.replaceContextDependency(INDEPENDENT));
KotlinType conditionType = typeInfo.getType();
if (conditionType != null && !components.builtIns.isBooleanOrSubtype(conditionType)) {
context.trace.report(TYPE_MISMATCH_IN_CONDITION.on(condition, conditionType));
}
return typeInfo.getDataFlowInfo();
}
return context.dataFlowInfo;
}
@NotNull
private KotlinTypeInfo getTypeInfoWhenOnlyOneBranchIsPresent(
@NotNull KtExpression presentBranch,
@NotNull LexicalWritableScope presentScope,
@NotNull DataFlowInfo presentInfo,
@NotNull DataFlowInfo otherInfo,
@NotNull ExpressionTypingContext context,
@NotNull KtIfExpression ifExpression,
boolean isStatement) {
ExpressionTypingContext newContext =
context
.replaceDataFlowInfo(presentInfo)
.replaceExpectedType(NO_EXPECTED_TYPE)
.replaceContextDependency(INDEPENDENT);
KotlinTypeInfo typeInfo =
components.expressionTypingServices.getBlockReturnedTypeWithWritableScope(
presentScope,
Collections.singletonList(presentBranch),
CoercionStrategy.NO_COERCION,
newContext);
KotlinType type = typeInfo.getType();
DataFlowInfo dataFlowInfo;
if (type != null && KotlinBuiltIns.isNothing(type)) {
dataFlowInfo = otherInfo;
} else {
dataFlowInfo = typeInfo.getDataFlowInfo().or(otherInfo);
}
return components
.dataFlowAnalyzer
.checkImplicitCast(
components.dataFlowAnalyzer.checkType(
typeInfo.replaceType(components.builtIns.getUnitType()), ifExpression, context),
ifExpression,
context,
isStatement)
.replaceDataFlowInfo(dataFlowInfo);
}
@Override
public KotlinTypeInfo visitReturnExpression(
@NotNull KtReturnExpression expression, ExpressionTypingContext context) {
KtElement labelTargetElement = LabelResolver.INSTANCE.resolveControlLabel(expression, context);
KtExpression returnedExpression = expression.getReturnedExpression();
KotlinType expectedType = NO_EXPECTED_TYPE;
KotlinType resultType = components.builtIns.getNothingType();
KtDeclaration parentDeclaration = PsiTreeUtil.getParentOfType(expression, KtDeclaration.class);
if (parentDeclaration instanceof KtParameter) {
// In a default value for parameter
context.trace.report(RETURN_NOT_ALLOWED.on(expression));
}
if (expression.getTargetLabel() == null) {
while (parentDeclaration instanceof KtMultiDeclaration) {
// TODO: It's hacking fix for KT-5100: Strange "Return is not allowed here" for
// multi-declaration initializer with elvis expression
parentDeclaration = PsiTreeUtil.getParentOfType(parentDeclaration, KtDeclaration.class);
}
assert parentDeclaration != null
: "Can't find parent declaration for " + expression.getText();
DeclarationDescriptor declarationDescriptor =
context.trace.get(DECLARATION_TO_DESCRIPTOR, parentDeclaration);
Pair<FunctionDescriptor, PsiElement> containingFunInfo =
BindingContextUtils.getContainingFunctionSkipFunctionLiterals(
declarationDescriptor, false);
FunctionDescriptor containingFunctionDescriptor = containingFunInfo.getFirst();
if (containingFunctionDescriptor != null) {
if (!InlineUtil.checkNonLocalReturnUsage(
containingFunctionDescriptor, expression, context.trace)
|| isClassInitializer(containingFunInfo)) {
// Unqualified, in a function literal
context.trace.report(RETURN_NOT_ALLOWED.on(expression));
resultType = ErrorUtils.createErrorType(RETURN_NOT_ALLOWED_MESSAGE);
}
expectedType =
getFunctionExpectedReturnType(
containingFunctionDescriptor, (KtElement) containingFunInfo.getSecond(), context);
} else {
// Outside a function
context.trace.report(RETURN_NOT_ALLOWED.on(expression));
resultType = ErrorUtils.createErrorType(RETURN_NOT_ALLOWED_MESSAGE);
}
} else if (labelTargetElement != null) {
SimpleFunctionDescriptor functionDescriptor = context.trace.get(FUNCTION, labelTargetElement);
if (functionDescriptor != null) {
expectedType =
getFunctionExpectedReturnType(functionDescriptor, labelTargetElement, context);
if (!InlineUtil.checkNonLocalReturnUsage(functionDescriptor, expression, context.trace)) {
// Qualified, non-local
context.trace.report(RETURN_NOT_ALLOWED.on(expression));
resultType = ErrorUtils.createErrorType(RETURN_NOT_ALLOWED_MESSAGE);
}
} else {
context.trace.report(NOT_A_RETURN_LABEL.on(expression, expression.getLabelName()));
}
}
if (returnedExpression != null) {
facade.getTypeInfo(
returnedExpression,
context
.replaceExpectedType(expectedType)
.replaceScope(context.scope)
.replaceContextDependency(INDEPENDENT));
} else {
if (expectedType != null
&& !noExpectedType(expectedType)
&& !KotlinBuiltIns.isUnit(expectedType)
&& !isDontCarePlaceholder(expectedType)) // for lambda with implicit return type Unit
{
context.trace.report(RETURN_TYPE_MISMATCH.on(expression, expectedType));
}
}
return components.dataFlowAnalyzer.createCheckedTypeInfo(resultType, context, expression);
}
public KotlinTypeInfo visitForExpression(
KtForExpression expression,
ExpressionTypingContext contextWithExpectedType,
boolean isStatement) {
if (!isStatement)
return components.dataFlowAnalyzer.illegalStatementType(
expression, contextWithExpectedType, facade);
ExpressionTypingContext context =
contextWithExpectedType
.replaceExpectedType(NO_EXPECTED_TYPE)
.replaceContextDependency(INDEPENDENT);
// Preliminary analysis
PreliminaryLoopVisitor loopVisitor = PreliminaryLoopVisitor.visitLoop(expression);
context =
context.replaceDataFlowInfo(
loopVisitor.clearDataFlowInfoForAssignedLocalVariables(context.dataFlowInfo));
KtExpression loopRange = expression.getLoopRange();
KotlinType expectedParameterType = null;
KotlinTypeInfo loopRangeInfo;
if (loopRange != null) {
ExpressionReceiver loopRangeReceiver =
getExpressionReceiver(facade, loopRange, context.replaceScope(context.scope));
loopRangeInfo = facade.getTypeInfo(loopRange, context);
if (loopRangeReceiver != null) {
expectedParameterType =
components.forLoopConventionsChecker.checkIterableConvention(
loopRangeReceiver, context);
}
} else {
loopRangeInfo = TypeInfoFactoryKt.noTypeInfo(context);
}
LexicalWritableScope loopScope = newWritableScopeImpl(context, "Scope with for-loop index");
KtParameter loopParameter = expression.getLoopParameter();
if (loopParameter != null) {
VariableDescriptor variableDescriptor =
createLoopParameterDescriptor(loopParameter, expectedParameterType, context);
components
.modifiersChecker
.withTrace(context.trace)
.checkModifiersForLocalDeclaration(loopParameter, variableDescriptor);
components.identifierChecker.checkDeclaration(loopParameter, context.trace);
loopScope.addVariableDescriptor(variableDescriptor);
} else {
KtMultiDeclaration multiParameter = expression.getMultiParameter();
if (multiParameter != null && loopRange != null) {
KotlinType elementType =
expectedParameterType == null
? ErrorUtils.createErrorType("Loop range has no type")
: expectedParameterType;
TransientReceiver iteratorNextAsReceiver = new TransientReceiver(elementType);
components.annotationResolver.resolveAnnotationsWithArguments(
loopScope, multiParameter.getModifierList(), context.trace);
components.multiDeclarationResolver.defineLocalVariablesFromMultiDeclaration(
loopScope, multiParameter, iteratorNextAsReceiver, loopRange, context);
components
.modifiersChecker
.withTrace(context.trace)
.checkModifiersForMultiDeclaration(multiParameter);
components
.modifiersChecker
.withTrace(context.trace)
.checkParameterHasNoValOrVar(multiParameter, VAL_OR_VAR_ON_LOOP_MULTI_PARAMETER);
components.identifierChecker.checkDeclaration(multiParameter, context.trace);
}
}
KtExpression body = expression.getBody();
KotlinTypeInfo bodyTypeInfo;
if (body != null) {
bodyTypeInfo =
components.expressionTypingServices.getBlockReturnedTypeWithWritableScope(
loopScope,
Collections.singletonList(body),
CoercionStrategy.NO_COERCION,
context.replaceDataFlowInfo(loopRangeInfo.getDataFlowInfo()));
} else {
bodyTypeInfo = loopRangeInfo;
}
return components
.dataFlowAnalyzer
.checkType(
bodyTypeInfo.replaceType(components.builtIns.getUnitType()),
expression,
contextWithExpectedType)
.replaceDataFlowInfo(loopRangeInfo.getDataFlowInfo());
}
public KotlinTypeInfo visitDoWhileExpression(
KtDoWhileExpression expression,
ExpressionTypingContext contextWithExpectedType,
boolean isStatement) {
if (!isStatement)
return components.dataFlowAnalyzer.illegalStatementType(
expression, contextWithExpectedType, facade);
ExpressionTypingContext context =
contextWithExpectedType
.replaceExpectedType(NO_EXPECTED_TYPE)
.replaceContextDependency(INDEPENDENT);
KtExpression body = expression.getBody();
LexicalScope conditionScope = context.scope;
// Preliminary analysis
PreliminaryLoopVisitor loopVisitor = PreliminaryLoopVisitor.visitLoop(expression);
context =
context.replaceDataFlowInfo(
loopVisitor.clearDataFlowInfoForAssignedLocalVariables(context.dataFlowInfo));
// Here we must record data flow information at the end of the body (or at the first jump, to be
// precise) and
// .and it with entrance data flow information, because do-while body is executed at least once
// See KT-6283
KotlinTypeInfo bodyTypeInfo;
if (body instanceof KtFunctionLiteralExpression) {
// As a matter of fact, function literal is always unused at this point
bodyTypeInfo = facade.getTypeInfo(body, context.replaceScope(context.scope));
} else if (body != null) {
LexicalWritableScope writableScope = newWritableScopeImpl(context, "do..while body scope");
conditionScope = writableScope;
List<KtExpression> block;
if (body instanceof KtBlockExpression) {
block = ((KtBlockExpression) body).getStatements();
} else {
block = Collections.singletonList(body);
}
bodyTypeInfo =
components.expressionTypingServices.getBlockReturnedTypeWithWritableScope(
writableScope, block, CoercionStrategy.NO_COERCION, context);
} else {
bodyTypeInfo = TypeInfoFactoryKt.noTypeInfo(context);
}
KtExpression condition = expression.getCondition();
DataFlowInfo conditionDataFlowInfo = checkCondition(conditionScope, condition, context);
DataFlowInfo dataFlowInfo;
// Without jumps out, condition is entered and false, with jumps out, we know nothing about it
if (!containsJumpOutOfLoop(expression, context)) {
dataFlowInfo =
components
.dataFlowAnalyzer
.extractDataFlowInfoFromCondition(condition, false, context)
.and(conditionDataFlowInfo);
} else {
dataFlowInfo = context.dataFlowInfo;
}
// Here we must record data flow information at the end of the body (or at the first jump, to be
// precise) and
// .and it with entrance data flow information, because do-while body is executed at least once
// See KT-6283
// NB: it's really important to do it for non-empty body which is not a function literal
// If it's a function literal, it appears always unused so it's no matter what we do at this
// point
if (body != null) {
// We should take data flow info from the first jump point,
// but without affecting changing variables
dataFlowInfo =
dataFlowInfo.and(
loopVisitor.clearDataFlowInfoForAssignedLocalVariables(
bodyTypeInfo.getJumpFlowInfo()));
}
return components
.dataFlowAnalyzer
.checkType(
bodyTypeInfo.replaceType(components.builtIns.getUnitType()),
expression,
contextWithExpectedType)
.replaceDataFlowInfo(dataFlowInfo);
}
public KotlinTypeInfo visitWhileExpression(
KtWhileExpression expression,
ExpressionTypingContext contextWithExpectedType,
boolean isStatement) {
if (!isStatement)
return components.dataFlowAnalyzer.illegalStatementType(
expression, contextWithExpectedType, facade);
ExpressionTypingContext context =
contextWithExpectedType
.replaceExpectedType(NO_EXPECTED_TYPE)
.replaceContextDependency(INDEPENDENT);
// Preliminary analysis
PreliminaryLoopVisitor loopVisitor = PreliminaryLoopVisitor.visitLoop(expression);
context =
context.replaceDataFlowInfo(
loopVisitor.clearDataFlowInfoForAssignedLocalVariables(context.dataFlowInfo));
KtExpression condition = expression.getCondition();
// Extract data flow info from condition itself without taking value into account
DataFlowInfo dataFlowInfo = checkCondition(context.scope, condition, context);
KtExpression body = expression.getBody();
KotlinTypeInfo bodyTypeInfo;
DataFlowInfo conditionInfo =
components
.dataFlowAnalyzer
.extractDataFlowInfoFromCondition(condition, true, context)
.and(dataFlowInfo);
if (body != null) {
LexicalWritableScope scopeToExtend =
newWritableScopeImpl(context, "Scope extended in while's condition");
bodyTypeInfo =
components.expressionTypingServices.getBlockReturnedTypeWithWritableScope(
scopeToExtend,
Collections.singletonList(body),
CoercionStrategy.NO_COERCION,
context.replaceDataFlowInfo(conditionInfo));
} else {
bodyTypeInfo = TypeInfoFactoryKt.noTypeInfo(conditionInfo);
}
// Condition is false at this point only if there is no jumps outside
if (!containsJumpOutOfLoop(expression, context)) {
dataFlowInfo =
components
.dataFlowAnalyzer
.extractDataFlowInfoFromCondition(condition, false, context)
.and(dataFlowInfo);
}
// Special case: while (true)
// In this case we must record data flow information at the nearest break / continue and
// .and it with entrance data flow information, because while body until break is executed at
// least once in this case
// See KT-6284
if (body != null && KtPsiUtil.isTrueConstant(condition)) {
// We should take data flow info from the first jump point,
// but without affecting changing variables
dataFlowInfo =
dataFlowInfo.and(
loopVisitor.clearDataFlowInfoForAssignedLocalVariables(
bodyTypeInfo.getJumpFlowInfo()));
}
return components
.dataFlowAnalyzer
.checkType(
bodyTypeInfo.replaceType(components.builtIns.getUnitType()),
expression,
contextWithExpectedType)
.replaceDataFlowInfo(dataFlowInfo);
}
public KotlinTypeInfo visitIfExpression(
KtIfExpression ifExpression,
ExpressionTypingContext contextWithExpectedType,
boolean isStatement) {
ExpressionTypingContext context = contextWithExpectedType.replaceExpectedType(NO_EXPECTED_TYPE);
KtExpression condition = ifExpression.getCondition();
DataFlowInfo conditionDataFlowInfo = checkCondition(context.scope, condition, context);
KtExpression elseBranch = ifExpression.getElse();
KtExpression thenBranch = ifExpression.getThen();
LexicalWritableScope thenScope = newWritableScopeImpl(context, "Then scope");
LexicalWritableScope elseScope = newWritableScopeImpl(context, "Else scope");
DataFlowInfo thenInfo =
components
.dataFlowAnalyzer
.extractDataFlowInfoFromCondition(condition, true, context)
.and(conditionDataFlowInfo);
DataFlowInfo elseInfo =
components
.dataFlowAnalyzer
.extractDataFlowInfoFromCondition(condition, false, context)
.and(conditionDataFlowInfo);
if (elseBranch == null) {
if (thenBranch != null) {
KotlinTypeInfo result =
getTypeInfoWhenOnlyOneBranchIsPresent(
thenBranch,
thenScope,
thenInfo,
elseInfo,
contextWithExpectedType,
ifExpression,
isStatement);
// If jump was possible, take condition check info as the jump info
return result.getJumpOutPossible()
? result.replaceJumpOutPossible(true).replaceJumpFlowInfo(conditionDataFlowInfo)
: result;
}
return TypeInfoFactoryKt.createTypeInfo(
components.dataFlowAnalyzer.checkImplicitCast(
components.builtIns.getUnitType(),
ifExpression,
contextWithExpectedType,
isStatement),
thenInfo.or(elseInfo));
}
if (thenBranch == null) {
return getTypeInfoWhenOnlyOneBranchIsPresent(
elseBranch,
elseScope,
elseInfo,
thenInfo,
contextWithExpectedType,
ifExpression,
isStatement);
}
KtPsiFactory psiFactory = KtPsiFactoryKt.KtPsiFactory(ifExpression);
KtBlockExpression thenBlock = psiFactory.wrapInABlockWrapper(thenBranch);
KtBlockExpression elseBlock = psiFactory.wrapInABlockWrapper(elseBranch);
Call callForIf =
createCallForSpecialConstruction(
ifExpression, ifExpression, Lists.newArrayList(thenBlock, elseBlock));
MutableDataFlowInfoForArguments dataFlowInfoForArguments =
createDataFlowInfoForArgumentsForIfCall(callForIf, thenInfo, elseInfo);
ResolvedCall<FunctionDescriptor> resolvedCall =
components.controlStructureTypingUtils.resolveSpecialConstructionAsCall(
callForIf,
ResolveConstruct.IF,
Lists.newArrayList("thenBranch", "elseBranch"),
Lists.newArrayList(false, false),
contextWithExpectedType,
dataFlowInfoForArguments);
BindingContext bindingContext = context.trace.getBindingContext();
KotlinTypeInfo thenTypeInfo =
BindingContextUtils.getRecordedTypeInfo(thenBranch, bindingContext);
KotlinTypeInfo elseTypeInfo =
BindingContextUtils.getRecordedTypeInfo(elseBranch, bindingContext);
assert thenTypeInfo != null
: "'Then' branch of if expression was not processed: " + ifExpression;
assert elseTypeInfo != null
: "'Else' branch of if expression was not processed: " + ifExpression;
boolean loopBreakContinuePossible =
thenTypeInfo.getJumpOutPossible() || elseTypeInfo.getJumpOutPossible();
KotlinType thenType = thenTypeInfo.getType();
KotlinType elseType = elseTypeInfo.getType();
DataFlowInfo thenDataFlowInfo = thenTypeInfo.getDataFlowInfo();
DataFlowInfo elseDataFlowInfo = elseTypeInfo.getDataFlowInfo();
boolean jumpInThen = thenType != null && KotlinBuiltIns.isNothing(thenType);
boolean jumpInElse = elseType != null && KotlinBuiltIns.isNothing(elseType);
DataFlowInfo resultDataFlowInfo;
if (thenType == null && elseType == null) {
resultDataFlowInfo = thenDataFlowInfo.or(elseDataFlowInfo);
} else if (thenType == null || (jumpInThen && !jumpInElse)) {
resultDataFlowInfo = elseDataFlowInfo;
} else if (elseType == null || (jumpInElse && !jumpInThen)) {
resultDataFlowInfo = thenDataFlowInfo;
} else {
resultDataFlowInfo = thenDataFlowInfo.or(elseDataFlowInfo);
}
KotlinType resultType = resolvedCall.getResultingDescriptor().getReturnType();
// If break or continue was possible, take condition check info as the jump info
return TypeInfoFactoryKt.createTypeInfo(
components.dataFlowAnalyzer.checkImplicitCast(
resultType, ifExpression, contextWithExpectedType, isStatement),
resultDataFlowInfo,
loopBreakContinuePossible,
conditionDataFlowInfo);
}