Be a bit more aggressive about expiring old soversions

Allow the source package responsible for the old soversion to be
completely expired if it wouldn't normally be kept, and all of it's
install packages have no external rdepends.

calm/package.py

@@ -1660,7 +1660,7 @@ def mark_fn(packages, po, v, certain_age, vault_requests):
     # shouldn't retain anything.
     #
     if pn.endswith('-debuginfo'):
-        return Freshness.conditional
+        return (Freshness.conditional, False)
 
     # - shared library packages which don't come from the current version of
     # source (i.e. is superseded or removed), have no packages from a
@@ -1674,25 +1674,25 @@ def mark_fn(packages, po, v, certain_age, vault_requests):
             mtime = po.tar(v).mtime
             if mtime < certain_age:
                 logging.debug("deprecated soversion package '%s' version '%s' mtime '%s' is over cut-off age" % (pn, v, time.strftime("%F %T %Z", time.localtime(mtime))))
-                return Freshness.conditional
+                return (Freshness.conditional, True)
 
     # - if package depends on anything in expired_provides
     #
     requires = po.version_hints[v].get('depends', [])
     if any(ep in requires for ep in past_mistakes.expired_provides):
         logging.debug("package '%s' version '%s' not retained as it requires a provide known to be expired" % (pn, v))
-        return Freshness.conditional
+        return (Freshness.conditional, False)
 
     # - marked via 'calm-tool vault'
     #
     es = po.srcpackage(v, suffix=False)
     if es in vault_requests:
         if v in vault_requests[es]:
             logging.info("package '%s' version '%s' not retained due vault request" % (pn, v))
-            return Freshness.conditional
+            return (Freshness.conditional, False)
 
     # otherwise, make no change
-    return Freshness.fresh
+    return (Freshness.fresh, False)
 
 
 #
@@ -1708,9 +1708,6 @@ def stale_packages(packages, vault_requests):
 
     # mark install packages for freshness
     for pn, po in packages.items():
-        if po.kind != Kind.binary:
-            continue
-
         # mark as fresh any versions explicitly listed in the keep: override
         # hint (unconditionally)
         for v in po.override_hints.get('keep', '').split():
@@ -1759,13 +1756,38 @@ def stale_packages(packages, vault_requests):
             if newer:
                 mark_package_fresh(packages, pn, v)
 
+    for pn, po in packages.items():
+        if po.kind != Kind.binary:
+            continue
+
         # overwrite with 'conditional' package retention mark if it meets
         # various criteria
         for v in sorted(po.versions(), key=lambda v: SetupVersion(v)):
-            mark = mark_fn(packages, po, v, certain_age, vault_requests)
+            (mark, others) = mark_fn(packages, po, v, certain_age, vault_requests)
             if mark != Freshness.fresh:
                 mark_package_fresh(packages, pn, v, mark)
 
+            # also look over the other install packages generated by the
+            # source...
+            if others:
+                es = po.version_hints[v].get('external-source', None)
+                if es:
+                    es_po = packages[es]
+                    # ... if the source package version doesn't count as kept ...
+                    #
+                    # (set above using same critera as for install package
+                    # e.g. we have an excess number of packages)
+                    logging.warning("considering other packages from source package '%s' version '%s'" % (es, v))
+                    if getattr(es_po.tar(v), 'fresh', Freshness.stale) != Freshness.fresh:
+                        # ...  additionally mark anything with no other-source
+                        # rdepends
+                        for opn in sorted(es_po.is_used_by):
+                            if v in packages[opn].versions():
+                                if not any(packages[p].srcpackage(v) != es for p in packages[opn].rdepends):
+                                    mark_package_fresh(packages, opn, v, mark)
+                                else:
+                                    logging.warning("package '%s' version '%s' retained due to being used" % (opn, v))
+
     # mark source packages as fresh if any install package which uses it is fresh
     for po in packages.values():
         if po.kind == Kind.source: