Christopher Chedeau
cf45afba61
- This brings in the flow test suite that contains a ton of JavaScript parsing edge cases - This creates snapshot tests using the pretty printer for all of them - If uncomment `RUN_AST_TESTS` line in `tests/run_specs.js`, it checks ast(pretty_print(x)) == ast(x). Right now, "178 failed, 197 passed, 375 of 377 total". So half of the tests are not passing, most of them are crashes and many of the rest are subtle issues.
30 lines
860 B
JavaScript
30 lines
860 B
JavaScript
/**
|
|
* Tests for intersections of object types
|
|
*
|
|
* @noflow
|
|
*/
|
|
|
|
// TODO we should give explicit errors for incompatibilities
|
|
// which make an intersection uninhabitable:
|
|
// - shared mutable properties with different types
|
|
// - different dictionary types
|
|
//
|
|
// Currently we give no such errors. Instead, we rely on
|
|
// the impossibility of providing a value for such a type
|
|
// to produce errors on value inflows. This is clearly
|
|
// suboptimal, since eg declared vars require no explicit
|
|
// provision of values. This leaves the impossible types
|
|
// free to flow downstream and satisfy impossible constraints.
|
|
|
|
// intersection of object types satisfies union of properties
|
|
declare var a: A;
|
|
var b: B = a;
|
|
|
|
// intersection of dictionary types:
|
|
declare var c: C;
|
|
var d: D = c; // ok
|
|
|
|
// dict type mismatch
|
|
type E = { [key: string]: string };
|
|
var e: E = c; // error
|