$ hg init

  $ echo a > a

  $ hg ci -Ama

  adding a

  $ hg an a

  0: a

  $ hg --config ui.strict=False an a

  0: a

  $ echo "[ui]" >> $HGRCPATH

  $ echo "strict=True" >> $HGRCPATH

  $ hg an a

  hg: unknown command 'an'

  Mercurial Distributed SCM

  basic commands:

   add           add the specified files on the next commit

   annotate      show changeset information by line for each file

   clone         make a copy of an existing repository

   commit        commit the specified files or all outstanding changes

   diff          diff repository (or selected files)

   export        dump the header and diffs for one or more changesets

   forget        forget the specified files on the next commit

   init          create a new repository in the given directory

   log           show revision history of entire repository or files

   merge         merge another revision into working directory

   pull          pull changes from the specified source

   push          push changes to the specified destination

   remove        remove the specified files on the next commit

   serve         start stand-alone webserver

   status        show changed files in the working directory

   summary       summarize working directory state

   update        update working directory (or switch revisions)

  (use 'hg help' for the full list of commands or 'hg -v' for details)

  [255]

  $ hg annotate a

  0: a

should succeed - up is an alias, not an abbreviation

  $ hg up

  0 files updated, 0 files merged, 0 files removed, 0 files unresolved