private KotlinTypeInfo getTypeOfLastExpressionInBlock(
@NotNull KtExpression statementExpression,
@NotNull ExpressionTypingContext context,
@NotNull CoercionStrategy coercionStrategyForLastExpression,
@NotNull ExpressionTypingInternals blockLevelVisitor) {
if (context.expectedType != NO_EXPECTED_TYPE) {
KotlinType expectedType;
if (context.expectedType == UNIT_EXPECTED_TYPE
|| // the first check is necessary to avoid invocation 'isUnit(UNIT_EXPECTED_TYPE)'
(coercionStrategyForLastExpression == COERCION_TO_UNIT
&& KotlinBuiltIns.isUnit(context.expectedType))) {
expectedType = UNIT_EXPECTED_TYPE;
} else {
expectedType = context.expectedType;
}
return blockLevelVisitor.getTypeInfo(
statementExpression, context.replaceExpectedType(expectedType), true);
}
KotlinTypeInfo result = blockLevelVisitor.getTypeInfo(statementExpression, context, true);
if (coercionStrategyForLastExpression == COERCION_TO_UNIT) {
boolean mightBeUnit = false;
if (statementExpression instanceof KtDeclaration) {
mightBeUnit = true;
}
if (statementExpression instanceof KtBinaryExpression) {
KtBinaryExpression binaryExpression = (KtBinaryExpression) statementExpression;
IElementType operationType = binaryExpression.getOperationToken();
//noinspection SuspiciousMethodCalls
if (operationType == KtTokens.EQ
|| OperatorConventions.ASSIGNMENT_OPERATIONS.containsKey(operationType)) {
mightBeUnit = true;
}
}
if (mightBeUnit) {
// ExpressionTypingVisitorForStatements should return only null or Unit for declarations and
// assignments,
// but (for correct assignment / initialization analysis) data flow info must be preserved
assert result.getType() == null || KotlinBuiltIns.isUnit(result.getType());
result = result.replaceType(expressionTypingComponents.builtIns.getUnitType());
}
}
return result;
}
/**
* 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);
}