view tests/test-histedit-templates.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.

Testing templating for histedit command

Setup

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > histedit=
  > [experimental]
  > evolution=createmarkers
  > EOF

  $ hg init repo
  $ cd repo
  $ for ch in a b c d; do echo foo > $ch; hg commit -Aqm "Added "$ch; done

  $ hg log -G -T "{rev}:{node|short} {desc}"
  @  3:62615734edd5 Added d
  |
  o  2:28ad74487de9 Added c
  |
  o  1:29becc82797a Added b
  |
  o  0:18d04c59bb5d Added a
  
Getting the JSON output for nodechanges

  $ hg histedit -Tjson --commands - 2>&1 <<EOF
  > pick 28ad74487de9 Added c
  > pick 62615734edd5 Added d
  > pick 18d04c59bb5d Added a
  > pick 29becc82797a Added b
  > EOF
  [
   {
    "nodechanges": {"18d04c59bb5d2d4090ad9a5b59bd6274adb63add": ["109f8ec895447f81b380ba8d4d8b66539ccdcb94"], "28ad74487de9599d00d81085be739c61fc340652": ["bff9e07c1807942b161dab768aa793b48e9a7f9d"], "29becc82797a4bc11ec8880b58eaecd2ab3e7760": ["f5dcf3b4db23f31f1aacf46c33d1393de303d26f"], "62615734edd52f06b6fb9c2beb429e4fe30d57b8": ["201423b441c84d9e6858daed653e0d22485c1cfa"]}
   }
  ]

  $ hg log -G -T "{rev}:{node|short} {desc}"
  @  7:f5dcf3b4db23 Added b
  |
  o  6:109f8ec89544 Added a
  |
  o  5:201423b441c8 Added d
  |
  o  4:bff9e07c1807 Added c
  
  $ hg histedit -T "{nodechanges|json}" --commands - 2>&1 <<EOF
  > pick bff9e07c1807 Added c
  > pick 201423b441c8 Added d
  > pick 109f8ec89544 Added a
  > roll f5dcf3b4db23 Added b
  > EOF
  {"109f8ec895447f81b380ba8d4d8b66539ccdcb94": ["8d01470bfeab64d3de13c49adb79d88790d38396"], "f3ec56a374bdbdf1953cacca505161442c6f3a3e": [], "f5dcf3b4db23f31f1aacf46c33d1393de303d26f": ["8d01470bfeab64d3de13c49adb79d88790d38396"]} (no-eol)