Narrowing from truthy unknown to object #37507
Merged
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With this PR, given a variable
x
of typeunknown
, the patternx && typeof x === 'object'
narrowsx
toobject
. Previously we'd narrow toobject | null
because a truthiness check applied tounknown
is stillunknown
(andunknown
includesnull
).Note that this is a targeted fix for a relatively common pattern. In an ideal world we'd be able to accurately represent types that are known to be truthy, but we currently don't have that ability.
Fixes #36870.