view tests/test-strict.t @ 33668:cde4cfeb6e3e stable

ui: restore behavior to ignore some I/O errors (issue5658)

e9646ff34d55 and 1bfb9a63b98e refactored ui methods to no longer
silently swallow some IOError instances. This is arguably the
correct thing to do. However, it had the unfortunate side-effect
of causing StdioError to bubble up to sensitive code like
transaction aborts, leading to an uncaught exceptions and failures
to e.g. roll back a transaction. This could occur when a remote
HTTP or SSH client connection dropped. The new behavior is
resulting in semi-frequent "abandonded transaction" errors on
multiple high-volume repositories at Mozilla.

This commit effectively reverts e9646ff34d55 and 1bfb9a63b98e to
restore the old behavior.

I agree with the principle that I/O errors shouldn't be ignored.
That makes this change... unfortunate. However, our hands are tied
for what to do on stable. I think the proper solution is for the
ui's behavior to be configurable (possibly via a context manager).
During critical sections like transaction rollback and abort, it
should be possible to suppress errors. But this feature would not
be appropriate on stable.

  $ 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