Shortly after tediously importing about thirty historical changesets
by hand, I realized I had imported the changes into the wrong
directory.

In such cases in the past, I have successfuly editing files in
_darcs/patches/ directly, but this time I thought I'd be clever,
serialize the patch bundle using darcs send -aO, and edit that.

That went perfectly, and as expected the hash didn't match anymore.  I
tried to apply it with --debug and --verbose, expecting Darcs to tell
me what the patch SHOULD be, so I could simply edit the hash at the
bottom of the patch bundle.  But Darcs didn't tell me, so I'll have to
spend another four hours tediously re-importing them.  Grr!

Why not just delete the hash?

On Sun, Nov 01, 2009 at 07:28:59PM +0000, Eric Kow wrote:
> Why not just delete the hash?

I didn't realize that darcs apply would blithely carry on if it found
no hash.  Maybe, then, this fact should be documented on a "doing
Wrong Things in Darcs" page on the wiki?

You're right -- patch37 wouldn't apply due to a hash mismatch, and
just deleting the hash made darcs go ahead and apply it.

I'd like to make this a wont-fix then, to avoid users being tempted to shoot
themselves in the foot.  

An evil FAQ on the wiki wouldn't be bad if worded carefully and also crafted not
to run into the eyes-glazing-over effect.  "You do NOT want to do these things.
 Check with darcs-users first".  People have a funny habit of thinking the evil
FAQ stuff applies to them... (but it's probably better for us to control the
Evil FAQ rather than let it come from folklore)