Map stale empty object type in union into fresh empty object type after spread is complete #34839
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…er spread is complete
sandersn
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Nov 12, 2019
jablko
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Nov 21, 2019
…er spread is complete (microsoft#34839) * Map stale empty object type in union into fresh empty object type after spread is complete * Accept minor baseline diff
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Fixes #34690
In the example given,
false | { foo: Record<never, never> }is mapped into{} | { foo: Record<never, never> }by the spread operator, except the{}isn't a fresh literal object type - it's just the plain ole stale vanilla empty object type used globally throughout the checker. This change maps that stale empty object into a brand new fresh empty object, as occurs in the non-union spread case.