tests/test-convert-authormap.t

abort: added logic for of hg abort

This is part of `GSoC19` project `Implement abort and
continue commands`. This patch is part of the `abort plan`.

This adds the basic logic for `hg abort`. This command
aborts an multistep operation like graft, histedit, rebase,
merge and unshelve if they are in an unfinished state.

The first part of the logic is determining the unfinished
operation from the state detection API under `statemod`.
This API is extended to support `hg abort` by adding a method
to register the abort logic as a function (here `abortfunc`).

Once the unfinished operation is determined the registered
logic is used to abort the command. The benefit of this kind
of framework is that any new extension developed can support
`hg abort` by registering the command and logic under
statedetection API.

`hg abort` currently supports `--dry-run/-n` flag only.
It is used to dry run `hg abort`

Further patches sequentially add support for `graft`, `rebase`,
`unshelve`, `histedit` and `merge`.

Differential Revision: https://phab.mercurial-scm.org/D6566

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > convert=
  > EOF

Prepare orig repo

  $ hg init orig
  $ cd orig
  $ echo foo > foo
  $ HGUSER='user name' hg ci -qAm 'foo'
  $ cd ..

Explicit --authors

  $ cat > authormap.txt <<EOF
  > user name = Long User Name
  > 
  > # comment
  > this line is ignored
  > EOF
  $ hg convert --authors authormap.txt orig new
  initializing destination new repository
  ignoring bad line in author map file authormap.txt: this line is ignored
  scanning source...
  sorting...
  converting...
  0 foo
  writing author map file $TESTTMP/new/.hg/authormap
  $ cat new/.hg/authormap
  user name=Long User Name
  $ hg -Rnew log
  changeset:   0:d89716e88087
  tag:         tip
  user:        Long User Name
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     foo
  
  $ rm -rf new

Implicit .hg/authormap

  $ hg init new
  $ mv authormap.txt new/.hg/authormap
  $ hg convert orig new
  ignoring bad line in author map file $TESTTMP/new/.hg/authormap: this line is ignored
  scanning source...
  sorting...
  converting...
  0 foo
  $ hg -Rnew log
  changeset:   0:d89716e88087
  tag:         tip
  user:        Long User Name
  date:        Thu Jan 01 00:00:00 1970 +0000
  summary:     foo