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Merge pull request #13483 from Microsoft/operatorsAndNullableTypes

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Improved checking of nullable operands in expressions
This commit is contained in:
Anders Hejlsberg
2017-01-16 15:03:48 -10:00
committed by GitHub
parent ed13dde154 221c0d7a39
commit d6fde0c07f
63 changed files with 3138 additions and 1104 deletions
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59
src/compiler/checker.ts
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@@ -12342,16 +12342,18 @@ namespace ts {
}
function checkNonNullExpression(node: Expression | QualifiedName) {
const type = checkExpression(node);
if (strictNullChecks) {
const kind = getFalsyFlags(type) & TypeFlags.Nullable;
if (kind) {
error(node, kind & TypeFlags.Undefined ? kind & TypeFlags.Null ?
Diagnostics.Object_is_possibly_null_or_undefined :
Diagnostics.Object_is_possibly_undefined :
Diagnostics.Object_is_possibly_null);
}
return getNonNullableType(type);
return checkNonNullType(checkExpression(node), node);
}
function checkNonNullType(type: Type, errorNode: Node): Type {
const kind = (strictNullChecks ? getFalsyFlags(type) : type.flags) & TypeFlags.Nullable;
if (kind) {
error(errorNode, kind & TypeFlags.Undefined ? kind & TypeFlags.Null ?
Diagnostics.Object_is_possibly_null_or_undefined :
Diagnostics.Object_is_possibly_undefined :
Diagnostics.Object_is_possibly_null);
const t = getNonNullableType(type);
return t.flags & (TypeFlags.Nullable | TypeFlags.Never) ? unknownType : t;
}
return type;
}
@@ -14491,6 +14493,7 @@ namespace ts {
case SyntaxKind.PlusToken:
case SyntaxKind.MinusToken:
case SyntaxKind.TildeToken:
checkNonNullType(operandType, node.operand);
if (maybeTypeOfKind(operandType, TypeFlags.ESSymbol)) {
error(node.operand, Diagnostics.The_0_operator_cannot_be_applied_to_type_symbol, tokenToString(node.operator));
}
@@ -14502,7 +14505,7 @@ namespace ts {
booleanType;
case SyntaxKind.PlusPlusToken:
case SyntaxKind.MinusMinusToken:
const ok = checkArithmeticOperandType(node.operand, getNonNullableType(operandType),
const ok = checkArithmeticOperandType(node.operand, checkNonNullType(operandType, node.operand),
Diagnostics.An_arithmetic_operand_must_be_of_type_any_number_or_an_enum_type);
if (ok) {
// run check only if former checks succeeded to avoid reporting cascading errors
@@ -14518,7 +14521,7 @@ namespace ts {
if (operandType === silentNeverType) {
return silentNeverType;
}
const ok = checkArithmeticOperandType(node.operand, getNonNullableType(operandType),
const ok = checkArithmeticOperandType(node.operand, checkNonNullType(operandType, node.operand),
Diagnostics.An_arithmetic_operand_must_be_of_type_any_number_or_an_enum_type);
if (ok) {
// run check only if former checks succeeded to avoid reporting cascading errors
@@ -14593,7 +14596,6 @@ namespace ts {
}
// NOTE: do not raise error if right is unknown as related error was already reported
if (!(isTypeAny(rightType) ||
rightType.flags & TypeFlags.Nullable ||
getSignaturesOfType(rightType, SignatureKind.Call).length ||
getSignaturesOfType(rightType, SignatureKind.Construct).length ||
isTypeSubtypeOf(rightType, globalFunctionType))) {
@@ -14606,6 +14608,8 @@ namespace ts {
if (leftType === silentNeverType || rightType === silentNeverType) {
return silentNeverType;
}
leftType = checkNonNullType(leftType, left);
rightType = checkNonNullType(rightType, right);
// TypeScript 1.0 spec (April 2014): 4.15.5
// The in operator requires the left operand to be of type Any, the String primitive type, or the Number primitive type,
// and the right operand to be of type Any, an object type, or a type parameter type.
@@ -14890,17 +14894,9 @@ namespace ts {
if (leftType === silentNeverType || rightType === silentNeverType) {
return silentNeverType;
}
// TypeScript 1.0 spec (April 2014): 4.19.1
// These operators require their operands to be of type Any, the Number primitive type,
// or an enum type. Operands of an enum type are treated
// as having the primitive type Number. If one operand is the null or undefined value,
// it is treated as having the type of the other operand.
// The result is always of the Number primitive type.
if (leftType.flags & TypeFlags.Nullable) leftType = rightType;
if (rightType.flags & TypeFlags.Nullable) rightType = leftType;
leftType = getNonNullableType(leftType);
rightType = getNonNullableType(rightType);
leftType = checkNonNullType(leftType, left);
rightType = checkNonNullType(rightType, right);
let suggestedOperator: SyntaxKind;
// if a user tries to apply a bitwise operator to 2 boolean operands
@@ -14925,16 +14921,11 @@ namespace ts {
if (leftType === silentNeverType || rightType === silentNeverType) {
return silentNeverType;
}
// TypeScript 1.0 spec (April 2014): 4.19.2
// The binary + operator requires both operands to be of the Number primitive type or an enum type,
// or at least one of the operands to be of type Any or the String primitive type.
// If one operand is the null or undefined value, it is treated as having the type of the other operand.
if (leftType.flags & TypeFlags.Nullable) leftType = rightType;
if (rightType.flags & TypeFlags.Nullable) rightType = leftType;
leftType = getNonNullableType(leftType);
rightType = getNonNullableType(rightType);
if (!isTypeOfKind(leftType, TypeFlags.Any | TypeFlags.StringLike) && !isTypeOfKind(rightType, TypeFlags.Any | TypeFlags.StringLike)) {
leftType = checkNonNullType(leftType, left);
rightType = checkNonNullType(rightType, right);
}
let resultType: Type;
if (isTypeOfKind(leftType, TypeFlags.NumberLike) && isTypeOfKind(rightType, TypeFlags.NumberLike)) {
@@ -14973,8 +14964,8 @@ namespace ts {
case SyntaxKind.LessThanEqualsToken:
case SyntaxKind.GreaterThanEqualsToken:
if (checkForDisallowedESSymbolOperand(operator)) {
leftType = getBaseTypeOfLiteralType(leftType);
rightType = getBaseTypeOfLiteralType(rightType);
leftType = getBaseTypeOfLiteralType(checkNonNullType(leftType, left));
rightType = getBaseTypeOfLiteralType(checkNonNullType(rightType, right));
if (!isTypeComparableTo(leftType, rightType) && !isTypeComparableTo(rightType, leftType)) {
reportOperatorError();
}