log: make opts entries optional (issue2423)

mercurial/cmdutil.py

@@ -996,7 +996,7 b' def walkchangerevs(repo, match, opts, pr'
         defrange = '%s:0' % repo['.'].rev()
     else:
         defrange = '-1:0'
-    revs = scmutil.revrange(repo, opts['rev'] or [defrange])
+    revs = scmutil.revrange(repo, opts.get('rev') or [defrange])
     if not revs:
         return []
     wanted = set()

mercurial/commands.py

@@ -4074,7 +4074,7 b' def log(ui, repo, *pats, **opts):'
         getrenamed = templatekw.getrenamedfn(repo, endrev=endrev)
 
     df = False
-    if opts["date"]:
+    if opts.get("date"):
         df = util.matchdate(opts["date"])
 
     branches = opts.get('branch', []) + opts.get('only_branch', [])