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 diff --change, --from, --to
$ hg init a
$ cd a
$ echo "first" > file.txt
$ hg add file.txt
$ hg commit -m 'first commit' # 0
$ echo "second" > file.txt
$ hg commit -m 'second commit' # 1
$ echo "third" > file.txt
$ hg commit -m 'third commit' # 2
$ hg diff --nodates --change 1
diff -r 4bb65dda5db4 -r e9b286083166 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-first
+second
$ hg diff --change e9b286083166
diff -r 4bb65dda5db4 -r e9b286083166 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +1,1 @@
-first
+second
Test --from and --to
$ hg diff --from . --rev .
abort: cannot specify both --from and --rev
[10]
$ hg diff --to . --rev .
abort: cannot specify both --to and --rev
[10]
$ hg diff --from . --change .
abort: cannot specify both --from and --change
[10]
$ hg diff --to . --change .
abort: cannot specify both --to and --change
[10]
$ echo dirty > file.txt
$ hg diff --from .
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +1,1 @@
-third
+dirty
$ hg diff --from . --reverse
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +1,1 @@
-dirty
+third
$ hg diff --to .
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +1,1 @@
-dirty
+third
$ hg diff --from 0 --to 2
diff -r 4bb65dda5db4 -r bf5ff72eb7e0 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +1,1 @@
-first
+third
$ hg diff --from 2 --to 0
diff -r bf5ff72eb7e0 -r 4bb65dda5db4 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -1,1 +1,1 @@
-third
+first
$ hg co -C .
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ..
Test dumb revspecs: top-level "x:y", "x:", ":y" and ":" ranges should be handled
as pairs even if x == y, but not for "f(x:y)" nor "x::y" (issue3474, issue4774)
$ hg clone -q a dumbspec
$ cd dumbspec
$ echo "wdir" > file.txt
$ hg diff -r 2:2
$ hg diff -r 2:.
$ hg diff -r 2:
$ hg diff -r :0
$ hg diff -r '2:first(2:2)'
$ hg diff -r 'first(2:2)' --nodates
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-third
+wdir
$ hg diff -r '(2:2)' --nodates
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-third
+wdir
$ hg diff -r 2::2 --nodates
diff -r bf5ff72eb7e0 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-third
+wdir
$ hg diff -r "2 and 1"
abort: empty revision range
[10]
$ cd ..
$ hg clone -qr0 a dumbspec-rev0
$ cd dumbspec-rev0
$ echo "wdir" > file.txt
$ hg diff -r :
$ hg diff -r 'first(:)' --nodates
diff -r 4bb65dda5db4 file.txt
--- a/file.txt
+++ b/file.txt
@@ -1,1 +1,1 @@
-first
+wdir
$ cd ..
Testing diff --change when merge:
$ cd a
$ for i in 1 2 3 4 5 6 7 8 9 10; do
> echo $i >> file.txt
> done
$ hg commit -m "lots of text" # 3
$ sed -e 's,^2$,x,' file.txt > file.txt.tmp
$ mv file.txt.tmp file.txt
$ hg commit -m "change 2 to x" # 4
$ hg up -r 3
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ sed -e 's,^8$,y,' file.txt > file.txt.tmp
$ mv file.txt.tmp file.txt
$ hg commit -m "change 8 to y"
created new head
$ hg up -C -r 4
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg merge -r 5
merging file.txt
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg commit -m "merge 8 to y" # 6
$ hg diff --change 5
diff -r ae119d680c82 -r 9085c5c02e52 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -6,6 +6,6 @@
5
6
7
-8
+y
9
10
must be similar to 'hg diff --change 5':
$ hg diff -c 6
diff -r 273b50f17c6d -r 979ca961fd2e file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -6,6 +6,6 @@
5
6
7
-8
+y
9
10
merge diff should show only manual edits to a merge:
$ hg diff --config diff.merge=yes -c 6
(no diff output is expected here)
Construct an "evil merge" that does something other than just the merge.
$ hg co ".^"
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg merge -r 5
merging file.txt
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ echo 11 >> file.txt
$ hg ci -m 'merge 8 to y with manual edit of 11' # 7
created new head
$ hg diff -c 7
diff -r 273b50f17c6d -r 8ad85e839ba7 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -6,6 +6,7 @@
5
6
7
-8
+y
9
10
+11
Contrast with the `hg diff -c 7` version above: only the manual edit shows
up, making it easy to identify changes someone is otherwise trying to sneak
into a merge.
$ hg diff --config diff.merge=yes -c 7
diff -r 8ad85e839ba7 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -9,3 +9,4 @@
y
9
10
+11
Set up a conflict.
$ hg co ".^"
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ sed -e 's,^8$,z,' file.txt > file.txt.tmp
$ mv file.txt.tmp file.txt
$ hg ci -m 'conflicting edit: 8 to z'
created new head
$ echo "this file is new in p1 of the merge" > new-file-p1.txt
$ hg ci -Am 'new file' new-file-p1.txt
$ hg log -r . --template 'p1 will be rev {rev}\n'
p1 will be rev 9
$ hg co 5
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo "this file is new in p2 of the merge" > new-file-p2.txt
$ hg ci -Am 'new file' new-file-p2.txt
created new head
$ hg log -r . --template 'p2 will be rev {rev}\n'
p2 will be rev 10
$ hg co -- 9
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg merge -r 10
merging file.txt
warning: conflicts while merging file.txt! (edit, then use 'hg resolve --mark')
1 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]
$ hg revert file.txt -r .
$ hg resolve -ma
(no more unresolved files)
$ hg commit -m 'merge conflicted edit'
Without diff.merge, it's a diff against p1
$ hg diff --config diff.merge=no -c 11
diff -r fd1f17c90d7c -r 5010caab09f6 new-file-p2.txt
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/new-file-p2.txt Thu Jan 01 00:00:00 1970 +0000
@@ -0,0 +1,1 @@
+this file is new in p2 of the merge
With diff.merge, it's a diff against the conflicted content.
$ hg diff --config diff.merge=yes -c 11
diff -r 5010caab09f6 file.txt
--- a/file.txt Thu Jan 01 00:00:00 1970 +0000
+++ b/file.txt Thu Jan 01 00:00:00 1970 +0000
@@ -6,12 +6,6 @@
5
6
7
-<<<<<<< local: fd1f17c90d7c - test: new file
z
-||||||| base: ae119d680c82 - test: lots of text
-8
-=======
-y
->>>>>>> other: d9e7de69eac3 - test: new file
9
10
There must _NOT_ be a .hg/merge directory leftover.
$ test ! -d .hg/merge
(No output is expected)
$ cd ..