view tests/test-automv.t @ 46706:93e9f448273c

rhg: Add support for automatic fallback to Python

`rhg` is a command-line application that can do a small subset of what
`hg` can. It is written entirely in Rust, which avoids the cost of starting
a Python interpreter and importing many Python modules.
In a script that runs many `hg` commands, this cost can add up.

However making users decide when to use `rhg` instead of `hg` is
not practical as we want the subset of supported functionality
to grow over time.

Instead we introduce "fallback" behavior where, when `rhg` encounters
something (a sub-command, a repository format, …) that is not implemented
in Rust-only, it does nothing but silently start a subprocess of
Python-based `hg` running the same command.
That way `rhg` becomes a drop-in replacement for `hg` that sometimes
goes faster. Whether Python is used should be an implementation detail
not apparent to users (other than through speed).

A new `fallback` value is added to the previously introduced
`rhg.on-unsupported` configuration key. When in this mode, the new
`rhg.fallback-executable` config is determine what command to use
to run a Python-based `hg`.

The previous `rhg.on-unsupported = abort-silent` configuration was designed
to let a wrapper script call `rhg` and then fall back to `hg` based on the
exit code. This is still available, but having fallback behavior built-in
in rhg might be easier for users instead of leaving that script "as an
exercise for the reader".

Using a subprocess like this is not idea, especially when `rhg` is to be
installed in `$PATH` as `hg`, since the other `hg.py` executable needs
to still be available… somewhere. Eventually this could be replaced
by using PyOxidizer to a have a single executable that embeds a Python
interpreter, but only starts it when needed.

Differential Revision: https://phab.mercurial-scm.org/D10093

Tests for the automv extension; detect moved files at commit time.

  $ cat >> $HGRCPATH << EOF
  > [extensions]
  > automv=
  > rebase=
  > EOF

Setup repo

  $ hg init repo
  $ cd repo

Test automv command for commit

  $ printf 'foo\nbar\nbaz\n' > a.txt
  $ hg add a.txt
  $ hg commit -m 'init repo with a'

mv/rm/add
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit -m 'msg'
  detected move of 1 files
  $ hg status --change . -C
  A b.txt
    a.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

mv/rm/add/modif
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ printf '\n' >> b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit -m 'msg'
  detected move of 1 files
  created new head
  $ hg status --change . -C
  A b.txt
    a.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

mv/rm/add/modif
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ printf '\nfoo\n' >> b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit -m 'msg'
  created new head
  $ hg status --change . -C
  A b.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

mv/rm/add/modif/changethreshold
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ printf '\nfoo\n' >> b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit --config automv.similarity='60' -m 'msg'
  detected move of 1 files
  created new head
  $ hg status --change . -C
  A b.txt
    a.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

mv
  $ mv a.txt b.txt
  $ hg status -C
  ! a.txt
  ? b.txt
  $ hg commit -m 'msg'
  nothing changed (1 missing files, see 'hg status')
  [1]
  $ hg status -C
  ! a.txt
  ? b.txt
  $ hg revert -aqC
  $ rm b.txt

mv/rm/add/notincommitfiles
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ echo 'bar' > c.txt
  $ hg add c.txt
  $ hg status -C
  A b.txt
  A c.txt
  R a.txt
  $ hg commit c.txt -m 'msg'
  created new head
  $ hg status --change . -C
  A c.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg up -r 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ hg rm a.txt
  $ echo 'bar' > c.txt
  $ hg add c.txt
  $ hg commit -m 'msg'
  detected move of 1 files
  created new head
  $ hg status --change . -C
  A b.txt
    a.txt
  A c.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

mv/rm/add/--no-automv
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit --no-automv -m 'msg'
  created new head
  $ hg status --change . -C
  A b.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

Test automv command for commit --amend

mv/rm/add
  $ echo 'c' > c.txt
  $ hg add c.txt
  $ hg commit -m 'revision to amend to'
  created new head
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit --amend -m 'amended'
  detected move of 1 files
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status --change . -C
  A b.txt
    a.txt
  A c.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

mv/rm/add/modif
  $ echo 'c' > c.txt
  $ hg add c.txt
  $ hg commit -m 'revision to amend to'
  created new head
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ printf '\n' >> b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit --amend -m 'amended'
  detected move of 1 files
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status --change . -C
  A b.txt
    a.txt
  A c.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

mv/rm/add/modif
  $ echo 'c' > c.txt
  $ hg add c.txt
  $ hg commit -m 'revision to amend to'
  created new head
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ printf '\nfoo\n' >> b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit --amend -m 'amended'
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status --change . -C
  A b.txt
  A c.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

mv/rm/add/modif/changethreshold
  $ echo 'c' > c.txt
  $ hg add c.txt
  $ hg commit -m 'revision to amend to'
  created new head
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ printf '\nfoo\n' >> b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit --amend --config automv.similarity='60' -m 'amended'
  detected move of 1 files
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status --change . -C
  A b.txt
    a.txt
  A c.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

mv
  $ echo 'c' > c.txt
  $ hg add c.txt
  $ hg commit -m 'revision to amend to'
  created new head
  $ mv a.txt b.txt
  $ hg status -C
  ! a.txt
  ? b.txt
  $ hg commit --amend -m 'amended'
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status -C
  ! a.txt
  ? b.txt
  $ hg up -Cr 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved

mv/rm/add/notincommitfiles
  $ echo 'c' > c.txt
  $ hg add c.txt
  $ hg commit -m 'revision to amend to'
  created new head
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ echo 'bar' > d.txt
  $ hg add d.txt
  $ hg status -C
  A b.txt
  A d.txt
  R a.txt
  $ hg commit --amend -m 'amended' d.txt
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status --change . -C
  A c.txt
  A d.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit --amend -m 'amended'
  detected move of 1 files
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status --change . -C
  A b.txt
    a.txt
  A c.txt
  A d.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 3 files removed, 0 files unresolved

mv/rm/add/--no-automv
  $ echo 'c' > c.txt
  $ hg add c.txt
  $ hg commit -m 'revision to amend to'
  created new head
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg add b.txt
  $ hg status -C
  A b.txt
  R a.txt
  $ hg commit --amend -m 'amended' --no-automv
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status --change . -C
  A b.txt
  A c.txt
  R a.txt
  $ hg up -r 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

mv/rm/commit/add/amend
  $ echo 'c' > c.txt
  $ hg add c.txt
  $ hg commit -m 'revision to amend to'
  created new head
  $ mv a.txt b.txt
  $ hg rm a.txt
  $ hg status -C
  R a.txt
  ? b.txt
  $ hg commit -m "removed a"
  $ hg add b.txt
  $ hg commit --amend -m 'amended'
  saved backup bundle to $TESTTMP/repo/.hg/strip-backup/*-amend.hg (glob)
  $ hg status --change . -C
  A b.txt
  R a.txt

error conditions

  $ cat >> $HGRCPATH << EOF
  > [automv]
  > similarity=110
  > EOF
  $ hg commit -m 'revision to amend to'
  abort: automv.similarity must be between 0 and 100
  [255]