Use checkExpression in checkSpreadExpression

Not checkExpressionCached. checkExpressionCached ignores ongoing control
flow analysis, which causes the following loop to make the compiler
recur infinitely:

```ts
let a = []
for (const x of []) {
    a = [...a]
}
```
This commit is contained in:
Nathan Shively-Sanders 2016-12-09 10:50:14 -08:00
parent f79fca7087
commit a52805f641

View File

@ -11252,13 +11252,7 @@ namespace ts {
}
function checkSpreadExpression(node: SpreadElement, contextualMapper?: TypeMapper): Type {
// It is usually not safe to call checkExpressionCached if we can be contextually typing.
// You can tell that we are contextually typing because of the contextualMapper parameter.
// While it is true that a spread element can have a contextual type, it does not do anything
// with this type. It is neither affected by it, nor does it propagate it to its operand.
// So the fact that contextualMapper is passed is not important, because the operand of a spread
// element is not contextually typed.
const arrayOrIterableType = checkExpressionCached(node.expression, contextualMapper);
const arrayOrIterableType = checkExpression(node.expression, contextualMapper);
return checkIteratedTypeOrElementType(arrayOrIterableType, node.expression, /*allowStringInput*/ false);
}