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.
Test 'hg log' with a bookmark
Create the repository
$ hg init Test-D8973
$ cd Test-D8973
$ echo "bar" > foo.txt
$ hg add foo.txt
$ hg commit -m "Add foo in 'default'"
Add a bookmark for topic X
$ hg branch -f sebhtml
marked working directory as branch sebhtml
(branches are permanent and global, did you want a bookmark?)
$ hg bookmark sebhtml/99991-topic-X
$ hg up sebhtml/99991-topic-X
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo "X" > x.txt
$ hg add x.txt
$ hg commit -m "Add x.txt in 'sebhtml/99991-topic-X'"
$ hg log -B sebhtml/99991-topic-X
changeset: 1:29f39dea9bf9
branch: sebhtml
bookmark: sebhtml/99991-topic-X
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Add x.txt in 'sebhtml/99991-topic-X'
Add a bookmark for topic Y
$ hg update default
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
(leaving bookmark sebhtml/99991-topic-X)
$ echo "Y" > y.txt
$ hg add y.txt
$ hg branch -f sebhtml
marked working directory as branch sebhtml
$ hg bookmark sebhtml/99992-topic-Y
$ hg up sebhtml/99992-topic-Y
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg commit -m "Add y.txt in 'sebhtml/99992-topic-Y'"
created new head
$ hg log -B sebhtml/99992-topic-Y
changeset: 2:11df7969cf8d
branch: sebhtml
bookmark: sebhtml/99992-topic-Y
tag: tip
parent: 0:eaea25376a59
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Add y.txt in 'sebhtml/99992-topic-Y'
The log of topic Y does not interfere with the log of topic X
$ hg log -B sebhtml/99991-topic-X
changeset: 1:29f39dea9bf9
branch: sebhtml
bookmark: sebhtml/99991-topic-X
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Add x.txt in 'sebhtml/99991-topic-X'
Merge topics Y and X in the default branch
$ hg update default
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
(leaving bookmark sebhtml/99992-topic-Y)
$ hg bookmark
sebhtml/99991-topic-X 1:29f39dea9bf9
sebhtml/99992-topic-Y 2:11df7969cf8d
$ hg merge sebhtml/99992-topic-Y
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m "Merge branch 'sebhtml/99992-topic-Y' into 'default'"
$ hg update default
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg merge sebhtml/99991-topic-X
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m "Merge branch 'sebhtml/99991-topic-X' into 'default'"
Check the log of topic X, topic Y, and default branch
$ hg log -B sebhtml/99992-topic-Y
$ hg log -B sebhtml/99991-topic-X
$ hg log -b default
changeset: 4:c26ba8c1e1cb
tag: tip
parent: 3:2189f3fb90d6
parent: 1:29f39dea9bf9
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Merge branch 'sebhtml/99991-topic-X' into 'default'
changeset: 3:2189f3fb90d6
parent: 0:eaea25376a59
parent: 2:11df7969cf8d
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Merge branch 'sebhtml/99992-topic-Y' into 'default'
changeset: 0:eaea25376a59
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Add foo in 'default'
Set up multiple bookmarked heads:
$ hg bookmark merged-head
$ hg up 1
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
(leaving bookmark merged-head)
$ echo "Z" > z.txt
$ hg ci -Am 'Add Z'
adding z.txt
$ hg bookmark topic-Z
$ hg log -GT '{rev}: {branch}, {bookmarks}\n'
@ 5: sebhtml, topic-Z
|
| o 4: default, merged-head
|/|
| o 3: default,
| |\
| | o 2: sebhtml, sebhtml/99992-topic-Y
| |/
o | 1: sebhtml, sebhtml/99991-topic-X
|/
o 0: default,
Multiple revisions under bookmarked head:
$ hg log -GT '{rev}: {branch}, {bookmarks}\n' -B merged-head
o 4: default, merged-head
|\
| ~
o 3: default,
|\
~ ~
Follows multiple bookmarks:
$ hg log -GT '{rev}: {branch}, {bookmarks}\n' -B merged-head -B topic-Z
@ 5: sebhtml, topic-Z
|
~
o 4: default, merged-head
|\
| ~
o 3: default,
|\
~ ~
Filter by bookmark and branch:
$ hg log -GT '{rev}: {branch}, {bookmarks}\n' -B merged-head -B topic-Z -b default
o 4: default, merged-head
|\
| ~
o 3: default,
|\
~ ~
Unknown bookmark:
$ hg log -B unknown
abort: bookmark 'unknown' does not exist
[10]
Shouldn't accept string-matcher syntax:
$ hg log -B 're:.*'
abort: bookmark 're:.*' does not exist
[10]