Bug#816645: devscripts testsuite failure on raspbian and presumablly other deratives that are not special-cased.

[Peter Green]

Package: devscripts
Version: 2.15.10

Note: this started as a mailing list post on devscripts-devel ( 
http://lists.alioth.debian.org/pipermail/devscripts-devel/2016-January/004781.html 
http://lists.alioth.debian.org/pipermail/devscripts-devel/2016-February/004793.html 
)

Starting with version 2.15.10 devscripts started failing to build in 
raspbian stretch. Sepcifically it failed with

testFileExclusion
uupdate --no-symlink --upstream-version 1+dfsg1 ../foo_1+dfsg1.orig.tar.xz
uupdate: New Release will be 1+dfsg1-0raspbian1.
uupdate: Untarring the new sourcecode archive ../foo_1+dfsg1.orig.tar.xz
uupdate: debian/source/format is "3.0 (quilt)".
uupdate: Auto-generating foo_0+dfsg1-1.debian.tar.xz
uupdate: Unpacking the debian/ directory from version 0+dfsg1-1 worked fine.
uupdate: Remember: Your current directory is the OLD sourcearchive!
uupdate: Do a "cd ../foo-1+dfsg1" to see the new package
ASSERT:uscan: Version should be 1+dfsg1-1 but 1+dfsg1-0raspbian1 expected:<1+dfsg1-0raspbian1>  but was:<1+dfsg1-1>


In version 2.15.10 the method used in uupdate to generate version 
suffixes was changed.

  SUFFIX="1"

  if which dpkg-vendor >/dev/null 2>&1; then
-    case "$(dpkg-vendor --query Vendor 2>/dev/null)" in
- "Ubuntu")
-            SUFFIX="0ubuntu1"
-            ;;
-    esac
+  VENDER="$(dpkg-vendor --query Vendor 2>/dev/null|tr 'A-Z' 'a-z')"
+  case "$VENDER" in
+  debian) SUFFIX="1" ;;
+  *) SUFFIX="0${VENDER}1" ;;
+  esac
+else
+  SUFFIX="1"
  fi

It's not clear to me why this change was made, the only thing I see in 
the changelog that seems related is

   [ Benjamin Drung ]
   * test_uscan: Fix failure in testFileExclusion due to wrong tarfile name
     test on Ubuntu.

but that talks about changing the test, not about changing uscan itself. 
It also doesn't seem to match up as the changelog entry talks about 
fixing Ubuntu but the change changes the behaviour for everything except 
Debian and Ubuntu.

If I modify test_uscan to expect -0<vendor>1 suffixes then 
testFileExclusion passes but other tests that passed before start to fail.

testWatch4WebNonNativeBZ2
uscan warn: Possible OpenPGP signature found at:
    http://localhost:50014/2.0/foo/ooo/foo-2.0.tar.gz.asc.
    Please consider adding opts=pgpsigurlmangle=s/$/.asc/
    to debian/watch.  see uscan(1) for more details.
uscan: Newest version of foo on remote site is 2.0, local version is 1.0
uscan:    => Newer package available from
       http://localhost:50014/2.0/foo/ooo/foo-2.0.tar.gz
ASSERT:uscan: Version should be 2.0-1 but 2.0-0raspbian1 
expected:<2.0-0raspbian1> but was:<2.0-1>

So it seems that uupdate is now using -0<vendor>1 on unknown derivatives 
but other tools are still using -1 on unknown derivatives. Thoughts on 
the best way to resolve this? (it seems to me that ideally the knowlage 
of how to generate version numbers for different derivatives would be 
centralised rather than duplicated).

Reverting the change to version number generation in uupdate results in 
a successful build on Raspbian.