view tests/test-issue619.t @ 46087:64292addbe67

diff: add --from and --to flags as clearer alternative to -r -r

I think it was mistake to let the `-r` flag accept two revisions in
`hg diff` in 98633e60067c (Support for 0, 1, or 2 diff revs,
2005-05-07). The command clearly acts on two revisions and having a
single flag to indicate which those are is unclear. It got worse when
it started accepting revsets as input.

This patch introduces `--from` and `--to` flags, each taking a single
revision and each defaulting to the working copy. That means that `hg

https://bz.mercurial-scm.org/619

  $ hg init
  $ echo a > a
  $ hg ci -Ama
  adding a

  $ echo b > b
  $ hg branch b
  marked working directory as branch b
  (branches are permanent and global, did you want a bookmark?)
  $ hg ci -Amb
  adding b

  $ hg co -C 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

Fast-forward:

  $ hg merge b
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg ci -Ammerge

Bogus fast-forward should fail:

  $ hg merge b
  abort: merging with a working directory ancestor has no effect
  [255]

Even with strange revset (issue4465)

  $ hg merge ::.
  abort: merging with a working directory ancestor has no effect
  [255]