Always. If they're a friend, they'll forgive, aid, and/or console. Why hide?
If they don't, they weren't your friend and giving up your integrity wouldn't have been worth it.
But that doesn't mean I won't lie to a specific friend to preserve a promise to them.
Lying in and of itself is not wrong. It depends on the motivation.
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And all that said, I have no doubt I slip up every once in a while.