Depends parsing: Properly handle empty depends / buildinfo: strict depends

pmb/build/buildinfo.py

@@ -40,7 +40,8 @@ def generate(args, apk_path, arch, suffix, apkbuild):
     installed = pmb.chroot.apk.installed(args, suffix)
     relevant = (apkbuild["makedepends"] + [apkbuild["pkgname"], "abuild",
                                            "build-base"])
-    relevant = pmb.parse.depends.recurse(args, relevant, arch, in_aports=False)
+    relevant = pmb.parse.depends.recurse(args, relevant, arch, in_aports=False,
+                                         strict=True)
     for pkgname in relevant:
         if pkgname == apkbuild["pkgname"]:
             continue

pmb/parse/depends.py

@@ -101,7 +101,8 @@ def recurse(args, pkgnames, arch=None, in_apkindexes=True, in_aports=True,
 
         # Append to todo/ret
         logging.verbose("-> Depends: " + str(depends))
-        todo += depends
+        if depends:
+            todo += depends
         ret.append(pkgname)
 
     return ret