view tests/test-merge4.t @ 49378:094a5fa3cf52 stable 6.2

procutil: make stream detection in make_line_buffered more correct and strict

In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.

Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.

The new logic is different in two ways:

First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.

Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.

The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.

  $ hg init
  $ echo This is file a1 > a
  $ hg add a
  $ hg commit -m "commit #0"
  $ echo This is file b1 > b
  $ hg add b
  $ hg commit -m "commit #1"
  $ hg update 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo This is file c1 > c
  $ hg add c
  $ hg commit -m "commit #2"
  created new head
  $ hg merge 1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ rm b
  $ echo This is file c22 > c

Test hg behaves when committing with a missing file added by a merge

  $ hg commit -m "commit #3"
  abort: cannot commit merge with missing files
  [255]


Test conflict*() revsets

# Bad usage
  $ hg log -r 'conflictlocal(foo)'
  hg: parse error: conflictlocal takes no arguments
  [10]
  $ hg log -r 'conflictother(foo)'
  hg: parse error: conflictother takes no arguments
  [10]
  $ hg co -C .
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
# No merge parents when not merging
  $ hg log -r 'conflictlocal() + conflictother()'
# No merge parents when there is no conflict
  $ hg merge 1
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg log -r 'conflictlocal() + conflictother()'
  $ hg co -C .
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo conflict > b
  $ hg ci -Aqm 'conflicting change to b'
  $ hg merge 1
  merging b
  warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg merge --abort' to abandon
  [1]
# Shows merge parents when there is a conflict
  $ hg log -r 'conflictlocal()' -T '{rev} {desc}\n'
  3 conflicting change to b
  $ hg log -r 'conflictother()' -T '{rev} {desc}\n'
  1 commit #1