This fixes the Windows regression I mentioned on IRC that was flagged by our
CI. It turned out that the bug is not Windows specific at all, it's just
that on Windows setCurrentDirectory with a http URL fails because that is
not a valid path name. Calling error in such cases lets us catch this when
testing on Linux, too.

A more principled solution would be to parse arguments that denote a repo
location immediately in the frontend and use the parsed form in the rest of
the code instead of the raw string.

3 patches for repository http://darcs.net/screened:

patch d7a11386d72441f3a00aa876360bdd8de21f3b4e
Author: Ben Franksen <ben.franksen@online.de>
Date:   Thu Jul  8 10:33:14 CEST 2021
  * setCurrentDirectory: call error if argument is a remote URL

patch 46c59a13b975e80ed869082745f09b423a4febee
Author: Ben Franksen <ben.franksen@online.de>
Date:   Sun Feb 28 11:44:48 CET 2021
  * fix in checkSuspendedStatus and maybeDisplaySuspendedStatus

  We must not try to access either of the rebase patch files if the repo
  location is a remote URL.

patch b2775f40b6521e2df3f555361b4ff9de6f4fc25c
Author: Ben Franksen <ben.franksen@online.de>
Date:   Thu Jul  8 20:37:14 CEST 2021
  * HasCallStack: withCurrentDirectory, withRepoDir

Attachments

• patch-preview.txt
• setcurrentdirectory_-call-error-if-argument-is-a-remote-url.dpatch

Looks good - one question:

>   * fix in checkSuspendedStatus and maybeDisplaySuspendedStatus

>  We must not try to access either of the rebase patch files if the repo
>  location is a remote URL.

Are there scenarios in which we call these functions for a remote repo?
Maybe those could be explained in a comment on the `isValidLocalPath`
guards if so.

>>    * fix in checkSuspendedStatus and maybeDisplaySuspendedStatus
> 
>>   We must not try to access either of the rebase patch files if the repo
>>   location is a remote URL.
> 
> Are there scenarios in which we call these functions for a remote repo?

Definitely maybeDisplaySuspendedStatus, it is call at the end of every 
RepoJob; think `darcs log --repo=...`, which IIRC made me stumble over this. 
Will add a comment.

checkSuspendedStatus is only called at the start of RebaseJob and 
RebaseAwareJob, so certainly not for repos at remote URLs. So this check is 
defensive and could be removed. Do you think I should?

> Definitely maybeDisplaySuspendedStatus, it is call at
> the end of every RepoJob; think `darcs log --repo=...`,
> which IIRC made me stumble over this. Will add a comment.

> checkSuspendedStatus is only called at the start of
> RebaseJob and RebaseAwareJob, so certainly not for
> repos at remote URLs. So this check is defensive and
> could be removed. Do you think I should?

No, it's fine to keep it, I was just surprised about both
cases. I think just documenting that it's defensive
would work.

Following up on review.

1 patch for repository http://darcs.net/screened:

patch 74049ba04f353c3d2afc1ac0d7ae66feacc2092d
Author: Ben Franksen <ben.franksen@online.de>
Date:   Wed Mar 22 23:33:50 CET 2023
  * document isValidLocalPath checks in D.R.Rebase

Attachments

• document-isvalidlocalpath-checks-in-d_r_rebase.dpatch
• patch-preview.txt