[pacman-dev] Bazaar branch check in makepkg

[Allan McRae]

On 09/01/15 08:18, David Macek wrote:
> Hi all.
> 
> I'm posting this on behalf of an MSYS2 user. We'd like to hear your opinion on removing this check from makepkg, which has been causing some troubles apparently.
> 
> The patch: https://raw.githubusercontent.com/renatosilva/MSYS2-packages/e006c48770281be1c952f2063ce0d5ccc4585d86/pacman/0003-Fix-Bazaar-cloning-support-in-makepkg.patch
> 
> His comment:
> 
> There was some manual check to know if the existing repository is actually a clone of the branch specified in $source. However this check needs to be semantic, not a simple string comparison. For example, I was blocked from building a PKGBUILD which uses a Bazaar repository in $source, because Bazaar was returning two different strings for the same location (for HTTP one was url-encoded while the other was not, and for local paths one was absolute while the other was relative).
> 
> While this may be a bug in Bazaar, the check is unreliable since the comparison is not semantic (http://foo.com/%2Bplus and http://foo.com/+plus obviously refer to the same location for example). It is also useless because the intention is updating the existing local clone. However, if the local clone is not a real clone of the repository specified in $source (which is what this buggy check tries to tell), next step which is a pull operation will fail anyway.

Why would it fail?  Given it is in a directory with a VCS PKGBUILD, it
probably is a valid checkout.  I quite often switch sources from the
upstream VCS repo, to other peoples copies if they have a development
branch that needs tested.

> I'm not sure why this kind of code is used but it looks pretty useless for any VCS at all. Maybe they wanted to avoid that non-clones successfully pulled from $source (for example if the non-clone simply just lacks some commits), but isn't this a corner case? Anyway, upstream may be interested in removing these checks for all VCS systems.

I have no interest in removing the check.  I do have interest in fixing
the bug...

Something like this should about do it...

for (( i = 0; i < length; i++ )); do
  local c="${1:i:1}"
  case $c in
    [a-zA-Z0-9.~_-]) printf "$c" ;;    # have I covered everything here?
    *) printf '%%%02X' "'$c"
  esac
done