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 the EOL hook
$ hg init main
$ cat > main/.hg/hgrc <<EOF
> [hooks]
> pretxnchangegroup = python:hgext.eol.hook
> EOF
$ hg clone main fork
updating to branch default
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd fork
Create repo
$ cat > .hgeol <<EOF
> [patterns]
> mixed.txt = BIN
> crlf.txt = CRLF
> **.txt = native
> EOF
$ hg add .hgeol
$ hg commit -m 'Commit .hgeol'
$ printf "first\nsecond\nthird\n" > a.txt
$ hg add a.txt
$ hg commit -m 'LF a.txt'
$ hg push ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files
$ printf "first\r\nsecond\r\nthird\n" > a.txt
$ hg commit -m 'CRLF a.txt'
$ hg push ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
error: pretxnchangegroup hook failed: end-of-line check failed:
a.txt in a8ee6548cd86 should not have CRLF line endings
transaction abort!
rollback completed
abort: end-of-line check failed:
a.txt in a8ee6548cd86 should not have CRLF line endings
[255]
$ printf "first\nsecond\nthird\n" > a.txt
$ hg commit -m 'LF a.txt (fixed)'
$ hg push ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 1 files
$ printf "first\nsecond\nthird\n" > crlf.txt
$ hg add crlf.txt
$ hg commit -m 'LF crlf.txt'
$ hg push ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
error: pretxnchangegroup hook failed: end-of-line check failed:
crlf.txt in 004ba2132725 should not have LF line endings
transaction abort!
rollback completed
abort: end-of-line check failed:
crlf.txt in 004ba2132725 should not have LF line endings
[255]
$ printf "first\r\nsecond\r\nthird\r\n" > crlf.txt
$ hg commit -m 'CRLF crlf.txt (fixed)'
$ hg push ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 1 files
$ printf "first\r\nsecond" > b.txt
$ hg add b.txt
$ hg commit -m 'CRLF b.txt'
$ hg push ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
error: pretxnchangegroup hook failed: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
transaction abort!
rollback completed
abort: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
[255]
$ hg up -r -2
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ printf "some\nother\nfile" > c.txt
$ hg add c.txt
$ hg commit -m "LF c.txt, b.txt doesn't exist here"
created new head
$ hg push -f ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
error: pretxnchangegroup hook failed: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
transaction abort!
rollback completed
abort: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
[255]
Test checkheadshook alias
$ cat > ../main/.hg/hgrc <<EOF
> [hooks]
> pretxnchangegroup = python:hgext.eol.checkheadshook
> EOF
$ hg push -f ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
error: pretxnchangegroup hook failed: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
transaction abort!
rollback completed
abort: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
[255]
We can fix the head and push again
$ hg up 6
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ printf "first\nsecond" > b.txt
$ hg ci -m "remove CRLF from b.txt"
$ hg push -f ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 2 files (+1 heads)
$ hg -R ../main rollback
repository tip rolled back to revision 5 (undo push)
Test it still fails with checkallhook
$ cat > ../main/.hg/hgrc <<EOF
> [hooks]
> pretxnchangegroup = python:hgext.eol.checkallhook
> EOF
$ hg push -f ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
error: pretxnchangegroup hook failed: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
transaction abort!
rollback completed
abort: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
[255]
But we can push the clean head
$ hg push -r7 -f ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
Test multiple files/revisions output
$ printf "another\r\nbad\r\none" > d.txt
$ hg add d.txt
$ hg ci -m "add d.txt"
$ hg push -f ../main
pushing to ../main
searching for changes
adding changesets
adding manifests
adding file changes
error: pretxnchangegroup hook failed: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
d.txt in a7040e68714f should not have CRLF line endings
transaction abort!
rollback completed
abort: end-of-line check failed:
b.txt in fbcf9b1025f5 should not have CRLF line endings
d.txt in a7040e68714f should not have CRLF line endings
[255]
$ cd ..