/**
* Visits block statements propagating data flow information from the first to the last.
* Determines block returned type and data flow information at the end of the block AND at the
* nearest jump point from the block beginning.
*/
/*package*/ KotlinTypeInfo getBlockReturnedTypeWithWritableScope(
@NotNull LexicalWritableScope scope,
@NotNull List<? extends KtElement> block,
@NotNull CoercionStrategy coercionStrategyForLastExpression,
@NotNull ExpressionTypingContext context) {
if (block.isEmpty()) {
return TypeInfoFactoryKt.createTypeInfo(
expressionTypingComponents.builtIns.getUnitType(), context);
}
ExpressionTypingInternals blockLevelVisitor =
new ExpressionTypingVisitorDispatcher.ForBlock(
expressionTypingComponents, annotationChecker, scope);
ExpressionTypingContext newContext =
context.replaceScope(scope).replaceExpectedType(NO_EXPECTED_TYPE);
KotlinTypeInfo result = TypeInfoFactoryKt.noTypeInfo(context);
// Jump point data flow info
DataFlowInfo beforeJumpInfo = newContext.dataFlowInfo;
boolean jumpOutPossible = false;
for (Iterator<? extends KtElement> iterator = block.iterator(); iterator.hasNext(); ) {
KtElement statement = iterator.next();
if (!(statement instanceof KtExpression)) {
continue;
}
KtExpression statementExpression = (KtExpression) statement;
if (!iterator.hasNext()) {
result =
getTypeOfLastExpressionInBlock(
statementExpression,
newContext.replaceExpectedType(context.expectedType),
coercionStrategyForLastExpression,
blockLevelVisitor);
if (result.getType() != null
&& statementExpression.getParent() instanceof KtBlockExpression) {
DataFlowValue lastExpressionValue =
DataFlowValueFactory.createDataFlowValue(
statementExpression, result.getType(), context);
DataFlowValue blockExpressionValue =
DataFlowValueFactory.createDataFlowValue(
(KtBlockExpression) statementExpression.getParent(), result.getType(), context);
result =
result.replaceDataFlowInfo(
result.getDataFlowInfo().assign(blockExpressionValue, lastExpressionValue));
}
} else {
result =
blockLevelVisitor.getTypeInfo(
statementExpression,
newContext.replaceContextDependency(ContextDependency.INDEPENDENT),
true);
}
DataFlowInfo newDataFlowInfo = result.getDataFlowInfo();
// If jump is not possible, we take new data flow info before jump
if (!jumpOutPossible) {
beforeJumpInfo = result.getJumpFlowInfo();
jumpOutPossible = result.getJumpOutPossible();
}
if (newDataFlowInfo != context.dataFlowInfo) {
newContext = newContext.replaceDataFlowInfo(newDataFlowInfo);
// We take current data flow info if jump there is not possible
}
blockLevelVisitor =
new ExpressionTypingVisitorDispatcher.ForBlock(
expressionTypingComponents, annotationChecker, scope);
}
return result.replaceJumpOutPossible(jumpOutPossible).replaceJumpFlowInfo(beforeJumpInfo);
}
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);
}
