packaging: rework version detection and declaration (issue4912)

Previously the -rc in our rc tags got dropped, meaning that those
packages looked newer to the packaging system than the later release
build. This rectifies the issue, though some damage may already have
been done on 3.6-rc builds.

I'm mostly cargo-culting the RPM version format - there don't appear
to be rules for RPM about how to handle this. Hopefully an RPM
enthusiast can fix up what I've done as a followup.

contrib/builddeb

@@ -46,6 +46,13 b' if [ ! -d .hg ]; then'
 fi
 
 gethgversion
+debver="$version"
+if [ -n "$type" ] ; then
+    debver="$debver~$type"
+fi
+if [ -n "$distance" ] ; then
+    debver="$debver+$distance-$node"
+fi
 
 control=debian/control
 changelog=debian/changelog
@@ -61,7 +68,7 b' if [ "$BUILD" ]; then'
 
     # This looks like sed -i, but sed -i behaves just differently enough
     # between BSD and GNU sed that I gave up and did the dumb thing.
-    sed "s/__VERSION__/$version/" < $changelog > $changelog.tmp
+    sed "s/__VERSION__/$debver/" < $changelog > $changelog.tmp
     date=$(date --rfc-2822)
     sed "s/__DATE__/$date/" < $changelog.tmp > $changelog
     rm $changelog.tmp
@@ -79,6 +86,6 b' if [ "$CLEANUP" ] ; then'
     find ../mercurial*.deb ../mercurial_*.build ../mercurial_*.changes \
           -type f -newer $control -print0 | \
       xargs -Inarf -0 mv narf "$OUTPUTDIR"
-    echo "Built packages for $version-$release:"
+    echo "Built packages for $debver:"
     find "$OUTPUTDIR" -type f -newer $control -name '*.deb'
 fi

contrib/buildrpm

@@ -49,6 +49,18 b' fi'
 
 gethgversion
 
+# TODO: handle distance/node set, and type set
+
+if [ -z "$type" ] ; then
+   release=1
+else
+    release=0.9_$type
+fi
+
+if [ -n "$distance" ] ; then
+    release=$release+$distance_$node
+fi
+
 if [ "$PYTHONVER" ]; then
     release=$release+$PYTHONVER
     RPMPYTHONVER=$PYTHONVER

contrib/packagelib.sh

@@ -1,3 +1,12 b''
+# Extract version number into 4 parts, some of which may be empty:
+#
+# version: the numeric part of the most recent tag. Will always look like 1.3.
+#
+# type: if an rc build, "rc", otherwise empty
+#
+# distance: the distance from the nearest tag, or empty if built from a tag
+#
+# node: the node|short hg was built from, or empty if built from a tag
 gethgversion() {
     make clean
     make local || make local PURE=--pure
@@ -7,13 +16,20 b' gethgversion() {'
 
     hgversion=`$HG version | sed -ne 's/.*(version \(.*\))$/\1/p'`
 
+    if echo $hgversion | grep + > /dev/null 2>&1 ; then
+        tmp=`echo $hgversion | cut -d+ -f 2`
+        hgversion=`echo $hgversion | cut -d+ -f 1`
+        distance=`echo $tmp | cut -d- -f 1`
+        node=`echo $tmp | cut -d- -f 2`
+    else
+        distance=''
+        node=''
+    fi
     if echo $hgversion | grep -- '-' > /dev/null 2>&1; then
-        # nightly build case, version is like 1.3.1+250-20b91f91f9ca
         version=`echo $hgversion | cut -d- -f1`
-        release=`echo $hgversion | cut -d- -f2 | sed -e 's/+.*//'`
+        type=`echo $hgversion | cut -d- -f2`
     else
-        # official tag, version is like 1.3.1
-        version=`echo $hgversion | sed -e 's/+.*//'`
-        release='0'
+        version=$hgversion
+        type=''
     fi
 }