Typed hash slice and except

[casperisfine]

Context

TypedHash inherits from HashWithIndifferentAccess, a while ago many methods like .except()would return a true HashWithIndifferentAccess, but recently they changed to return an instance of the same class than the initial hash.

First slice in 2017 https://github.com/rails/rails/commit/d6f3b91aaa4af88eda2344629afed64640d51e0f and more recently except in 2019: https://github.com/rails/rails/commit/a805d72e901f81f5b043dfd9904b80ce93ebfc01#diff-9f4b3d7342097a6f22290f147a09b77b

The problem with this is that TypedHash can contain default values for keys, so if you clear a a key with a default, it will be reset on the new instance, which makes for confusing defaults.

e.g.: {age: 42}.except(:age) => {age: 0} while you'd likely expect {}.

Solution

We first cast to HashWIthIndifferentAccess before calling these methods.

@rafaelfranca thoughts?

[rafaelfranca]

Ah, when you say a default is not the Hash.default value but a list of defaults values that are applied in the constructor of this object.

[coveralls]

Coverage increased (+0.01%) to 94.927% when pulling 1711765a2586362a37640d2c3b25600878fbb883 on typed-hash-slice-and-except into 0f47084d6a0e0e142f6c5d26d53a87ae924751d1 on master.

[coveralls]

Coverage increased (+0.01%) to 94.927% when pulling 1711765a2586362a37640d2c3b25600878fbb883 on typed-hash-slice-and-except into 0f47084d6a0e0e142f6c5d26d53a87ae924751d1 on master.