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.
$ HGMERGE=true; export HGMERGE
$ hg init r1
$ cd r1
$ echo a > a
$ hg addremove
adding a
$ hg commit -m "1"
$ hg clone . ../r2
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ../r2
$ hg up
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo abc > a
$ hg diff --nodates
diff -r c19d34741b0a a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-a
+abc
$ cd ../r1
$ echo b > b
$ echo a2 > a
$ hg addremove
adding b
$ hg commit -m "2"
$ cd ../r2
$ hg -q pull ../r1
$ hg status
M a
$ hg parents
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 1
$ hg --debug up
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb
b: remote created -> g
getting b
preserving a for resolve of a
a: versions differ -> m
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg --debug up 0
starting 4 threads for background file closing (?)
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: 1e71731e6fbb, local: 1e71731e6fbb+, remote: c19d34741b0a
b: other deleted -> r
removing b
starting 4 threads for background file closing (?)
preserving a for resolve of a
a: versions differ -> m
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@1e71731e6fbb+ other a@c19d34741b0a ancestor a@1e71731e6fbb
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
0 files updated, 1 files merged, 1 files removed, 0 files unresolved
$ hg parents
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 1
$ hg --debug up
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: c19d34741b0a, local: c19d34741b0a+, remote: 1e71731e6fbb
b: remote created -> g
getting b
preserving a for resolve of a
a: versions differ -> m
picked tool 'true' for a (binary False symlink False changedelete False)
merging a
my a@c19d34741b0a+ other a@1e71731e6fbb ancestor a@c19d34741b0a
launching merge tool: true *$TESTTMP/r2/a* * * (glob)
merge tool returned: 0
1 files updated, 1 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg -v history
changeset: 1:1e71731e6fbb
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: a b
description:
2
changeset: 0:c19d34741b0a
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files: a
description:
1
$ hg diff --nodates
diff -r 1e71731e6fbb a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-a2
+abc
create a second head
$ cd ../r1
$ hg up 0
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo b2 > b
$ echo a3 > a
$ hg addremove
adding b
$ hg commit -m "3"
created new head
$ cd ../r2
$ hg -q pull ../r1
$ hg status
M a
$ hg parents
changeset: 1:1e71731e6fbb
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 2
$ hg --debug up
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
updated to "1e71731e6fbb: 2"
1 other heads for branch "default"
test conflicting untracked files
$ hg up -qC 0
$ echo untracked > b
$ hg st
? b
$ hg up 1
b: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[20]
$ rm b
test conflicting untracked ignored file
$ hg up -qC 0
$ echo ignored > .hgignore
$ hg add .hgignore
$ hg ci -m 'add .hgignore'
created new head
$ echo ignored > ignored
$ hg add ignored
$ hg ci -m 'add ignored file'
$ hg up -q 'desc("add .hgignore")'
$ echo untracked > ignored
$ hg st
$ hg up 'desc("add ignored file")'
ignored: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[20]
test a local add
$ cd ..
$ hg init a
$ hg init b
$ echo a > a/a
$ echo a > b/a
$ hg --cwd a commit -A -m a
adding a
$ cd b
$ hg add a
$ hg pull -u ../a
pulling from ../a
requesting all changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets cb9a9f314b8b
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg st
test updating backwards through a rename
$ hg mv a b
$ hg ci -m b
$ echo b > b
$ hg up -q 0
$ hg st
M a
$ hg diff --nodates
diff -r cb9a9f314b8b a
--- a/a
+++ b/a
@@ -1,1 +1,1 @@
-a
+b
test for superfluous filemerge of clean files renamed in the past
$ hg up -qC tip
$ echo c > c
$ hg add c
$ hg up -qt:fail 0
$ cd ..