streamclone: define first iteration of version 2 of stream format
(This patch is based on a first draft from Gregory Szorc, with deeper rework)
Version 1 of the stream clone format was invented many years ago and suffers
from a few deficiencies:
1) Filenames are stored in store-encoded (on filesystem) form rather than in
their internal form. This makes future compatibility with new store
filename encodings more difficult.
2) File entry "headers" consist of a newline of the file name followed by the
string file size. Converting strings to integers is avoidable overhead. We
can't store filenames with newlines (manifests have this limitation as
well, so it isn't a major concern). But the big concern here is the
necessity for readline(). Scanning for newlines means reading ahead and
that means extra buffer allocations and slicing (in Python) and this makes
performance suffer.
3) Filenames aren't compressed optimally. Filenames should be compressed well
since there is a lot of repeated data. However, since they are scattered
all over the stream (with revlog data in between), they typically fall
outside the window size of the compressor and don't compress.
4) It can only exchange stored based content, being able to exchange caches
too would be nice.
5) It is limited to a stream-based protocol and isn't suitable for an on-disk
format for general repository reading because the offset of individual file
entries requires scanning the entire file to find file records.
As part of enabling streaming clones to work in bundle2, #2 proved to have a
significant negative impact on performance. Since bundle2 provides the
opportunity to start fresh, Gregory Szorc figured he would take the
opportunity to invent a new streaming clone data format.
The new format devised in this series addresses #1, #2, and #4. It punts on #3
because it was complex without yielding a significant gain and on #5 because
devising a new store format that "packs" multiple revlogs into a single
"packed revlog" is massive scope bloat. However, this v2 format might be
suitable for streaming into a "packed revlog" with minimal processing. If it
works, great. If not, we can always invent stream format when it is needed.
This patch only introduces the bases of the format. We'll get it usable through
bundle2 first, then we'll extend the format in future patches to bring it to its
full potential (especially #4).
$ hg init
$ mkdir d1 d1/d11 d2
$ echo d1/a > d1/a
$ echo d1/ba > d1/ba
$ echo d1/a1 > d1/d11/a1
$ echo d1/b > d1/b
$ echo d2/b > d2/b
$ hg add d1/a d1/b d1/ba d1/d11/a1 d2/b
$ hg commit -m "1"
rename a single file
$ hg rename d1/d11/a1 d2/c
$ hg --config ui.portablefilenames=abort rename d1/a d1/con.xml
abort: filename contains 'con', which is reserved on Windows: d1/con.xml
[255]
$ hg sum
parent: 0:9b4b6e7b2c26 tip
1
branch: default
commit: 1 renamed
update: (current)
phases: 1 draft
$ hg status -C
A d2/c
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/c
rename a single file using absolute paths
$ hg rename `pwd`/d1/d11/a1 `pwd`/d2/c
$ hg status -C
A d2/c
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/c
rename --after a single file
$ mv d1/d11/a1 d2/c
$ hg rename --after d1/d11/a1 d2/c
$ hg status -C
A d2/c
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/c
rename --after a single file when src and tgt already tracked
$ mv d1/d11/a1 d2/c
$ hg addrem -s 0
removing d1/d11/a1
adding d2/c
$ hg rename --after d1/d11/a1 d2/c
$ hg status -C
A d2/c
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/c
rename --after a single file to a nonexistent target filename
$ hg rename --after d1/a dummy
d1/a: not recording move - dummy does not exist
move a single file to an existing directory
$ hg rename d1/d11/a1 d2
$ hg status -C
A d2/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/a1
move --after a single file to an existing directory
$ mv d1/d11/a1 d2
$ hg rename --after d1/d11/a1 d2
$ hg status -C
A d2/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/a1
rename a file using a relative path
$ (cd d1/d11; hg rename ../../d2/b e)
$ hg status -C
A d1/d11/e
d2/b
R d2/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/d11/e
rename --after a file using a relative path
$ (cd d1/d11; mv ../../d2/b e; hg rename --after ../../d2/b e)
$ hg status -C
A d1/d11/e
d2/b
R d2/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/d11/e
rename directory d1 as d3
$ hg rename d1/ d3
moving d1/a to d3/a
moving d1/b to d3/b
moving d1/ba to d3/ba
moving d1/d11/a1 to d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
rename --after directory d1 as d3
$ mv d1 d3
$ hg rename --after d1 d3
moving d1/a to d3/a
moving d1/b to d3/b
moving d1/ba to d3/ba
moving d1/d11/a1 to d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move a directory using a relative path
$ (cd d2; mkdir d3; hg rename ../d1/d11 d3)
moving ../d1/d11/a1 to d3/d11/a1
$ hg status -C
A d2/d3/d11/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d3
move --after a directory using a relative path
$ (cd d2; mkdir d3; mv ../d1/d11 d3; hg rename --after ../d1/d11 d3)
moving ../d1/d11/a1 to d3/d11/a1
$ hg status -C
A d2/d3/d11/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d3
move directory d1/d11 to an existing directory d2 (removes empty d1)
$ hg rename d1/d11/ d2
moving d1/d11/a1 to d2/d11/a1
$ hg status -C
A d2/d11/a1
d1/d11/a1
R d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d11
move directories d1 and d2 to a new directory d3
$ mkdir d3
$ hg rename d1 d2 d3
moving d1/a to d3/d1/a
moving d1/b to d3/d1/b
moving d1/ba to d3/d1/ba
moving d1/d11/a1 to d3/d1/d11/a1
moving d2/b to d3/d2/b
$ hg status -C
A d3/d1/a
d1/a
A d3/d1/b
d1/b
A d3/d1/ba
d1/ba
A d3/d1/d11/a1
d1/d11/a1
A d3/d2/b
d2/b
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
R d2/b
$ hg update -C
5 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move --after directories d1 and d2 to a new directory d3
$ mkdir d3
$ mv d1 d2 d3
$ hg rename --after d1 d2 d3
moving d1/a to d3/d1/a
moving d1/b to d3/d1/b
moving d1/ba to d3/d1/ba
moving d1/d11/a1 to d3/d1/d11/a1
moving d2/b to d3/d2/b
$ hg status -C
A d3/d1/a
d1/a
A d3/d1/b
d1/b
A d3/d1/ba
d1/ba
A d3/d1/d11/a1
d1/d11/a1
A d3/d2/b
d2/b
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
R d2/b
$ hg update -C
5 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move everything under directory d1 to existing directory d2, do not
overwrite existing files (d2/b)
$ hg rename d1/* d2
d2/b: not overwriting - file already committed
(hg rename --force to replace the file by recording a rename)
moving d1/d11/a1 to d2/d11/a1
$ hg status -C
A d2/a
d1/a
A d2/ba
d1/ba
A d2/d11/a1
d1/d11/a1
R d1/a
R d1/ba
R d1/d11/a1
$ diff -u d1/b d2/b
--- d1/b * (glob)
+++ d2/b * (glob)
@@ * (glob)
-d1/b
+d2/b
[1]
$ hg update -C
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d2/a d2/ba d2/d11/a1
attempt to move one file into a non-existent directory
$ hg rename d1/a dx/
abort: destination dx/ is not a directory
[255]
$ hg status -C
$ hg update -C
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
attempt to move potentially more than one file into a non-existent directory
$ hg rename 'glob:d1/**' dx
abort: with multiple sources, destination must be an existing directory
[255]
move every file under d1 to d2/d21
$ mkdir d2/d21
$ hg rename 'glob:d1/**' d2/d21
moving d1/a to d2/d21/a
moving d1/b to d2/d21/b
moving d1/ba to d2/d21/ba
moving d1/d11/a1 to d2/d21/a1
$ hg status -C
A d2/d21/a
d1/a
A d2/d21/a1
d1/d11/a1
A d2/d21/b
d1/b
A d2/d21/ba
d1/ba
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d21
move --after some files under d1 to d2/d21
$ mkdir d2/d21
$ mv d1/a d1/d11/a1 d2/d21
$ hg rename --after 'glob:d1/**' d2/d21
moving d1/a to d2/d21/a
d1/b: not recording move - d2/d21/b does not exist
d1/ba: not recording move - d2/d21/ba does not exist
moving d1/d11/a1 to d2/d21/a1
$ hg status -C
A d2/d21/a
d1/a
A d2/d21/a1
d1/d11/a1
R d1/a
R d1/d11/a1
$ hg update -C
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d21
move every file under d1 starting with an 'a' to d2/d21 (regexp)
$ mkdir d2/d21
$ hg rename 're:d1/([^a][^/]*/)*a.*' d2/d21
moving d1/a to d2/d21/a
moving d1/d11/a1 to d2/d21/a1
$ hg status -C
A d2/d21/a
d1/a
A d2/d21/a1
d1/d11/a1
R d1/a
R d1/d11/a1
$ hg update -C
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d2/d21
attempt to overwrite an existing file
$ echo "ca" > d1/ca
$ hg rename d1/ba d1/ca
d1/ca: not overwriting - file exists
(hg rename --after to record the rename)
$ hg status -C
? d1/ca
$ hg update -C
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
forced overwrite of an existing file
$ echo "ca" > d1/ca
$ hg rename --force d1/ba d1/ca
$ hg status -C
A d1/ca
d1/ba
R d1/ba
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/ca
attempt to overwrite an existing broken symlink
#if symlink
$ ln -s ba d1/ca
$ hg rename --traceback d1/ba d1/ca
d1/ca: not overwriting - file exists
(hg rename --after to record the rename)
$ hg status -C
? d1/ca
$ hg update -C
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/ca
replace a symlink with a file
$ ln -s ba d1/ca
$ hg rename --force d1/ba d1/ca
$ hg status -C
A d1/ca
d1/ba
R d1/ba
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/ca
#endif
do not copy more than one source file to the same destination file
$ mkdir d3
$ hg rename d1/* d2/* d3
moving d1/d11/a1 to d3/d11/a1
d3/b: not overwriting - d2/b collides with d1/b
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move a whole subtree with "hg rename ."
$ mkdir d3
$ (cd d1; hg rename . ../d3)
moving a to ../d3/d1/a
moving b to ../d3/d1/b
moving ba to ../d3/d1/ba
moving d11/a1 to ../d3/d1/d11/a1
$ hg status -C
A d3/d1/a
d1/a
A d3/d1/b
d1/b
A d3/d1/ba
d1/ba
A d3/d1/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move a whole subtree with "hg rename --after ."
$ mkdir d3
$ mv d1/* d3
$ (cd d1; hg rename --after . ../d3)
moving a to ../d3/a
moving b to ../d3/b
moving ba to ../d3/ba
moving d11/a1 to ../d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
move the parent tree with "hg rename .."
$ (cd d1/d11; hg rename .. ../../d3)
moving ../a to ../../d3/a
moving ../b to ../../d3/b
moving ../ba to ../../d3/ba
moving a1 to ../../d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/b
d1/b
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
skip removed files
$ hg remove d1/b
$ hg rename d1 d3
moving d1/a to d3/a
moving d1/ba to d3/ba
moving d1/d11/a1 to d3/d11/a1
$ hg status -C
A d3/a
d1/a
A d3/ba
d1/ba
A d3/d11/a1
d1/d11/a1
R d1/a
R d1/b
R d1/ba
R d1/d11/a1
$ hg update -C
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf d3
transitive rename
$ hg rename d1/b d1/bb
$ hg rename d1/bb d1/bc
$ hg status -C
A d1/bc
d1/b
R d1/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/bc
transitive rename --after
$ hg rename d1/b d1/bb
$ mv d1/bb d1/bc
$ hg rename --after d1/bb d1/bc
$ hg status -C
A d1/bc
d1/b
R d1/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/bc
$ echo "# idempotent renames (d1/b -> d1/bb followed by d1/bb -> d1/b)"
# idempotent renames (d1/b -> d1/bb followed by d1/bb -> d1/b)
$ hg rename d1/b d1/bb
$ echo "some stuff added to d1/bb" >> d1/bb
$ hg rename d1/bb d1/b
$ hg status -C
M d1/b
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
overwriting with renames (issue1959)
$ hg rename d1/a d1/c
$ hg rename d1/b d1/a
$ hg status -C
M d1/a
d1/b
A d1/c
d1/a
R d1/b
$ hg diff --git
diff --git a/d1/a b/d1/a
--- a/d1/a
+++ b/d1/a
@@ -1,1 +1,1 @@
-d1/a
+d1/b
diff --git a/d1/b b/d1/b
deleted file mode 100644
--- a/d1/b
+++ /dev/null
@@ -1,1 +0,0 @@
-d1/b
diff --git a/d1/a b/d1/c
copy from d1/a
copy to d1/c
$ hg update -C
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm d1/c # The file was marked as added, so 'hg update' action was 'forget'
check illegal path components
$ hg rename d1/d11/a1 .hg/foo
abort: path contains illegal component: .hg/foo
[255]
$ hg status -C
$ hg rename d1/d11/a1 ../foo
abort: ../foo not under root '$TESTTMP'
[255]
$ hg status -C
$ mv d1/d11/a1 .hg/foo
$ hg rename --after d1/d11/a1 .hg/foo
abort: path contains illegal component: .hg/foo
[255]
$ hg status -C
! d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm .hg/foo
$ hg rename d1/d11/a1 .hg
abort: path contains illegal component: .hg/a1
[255]
$ hg --config extensions.largefiles= rename d1/d11/a1 .hg
The fsmonitor extension is incompatible with the largefiles extension and has been disabled. (fsmonitor !)
abort: path contains illegal component: .hg/a1
[255]
$ hg status -C
$ hg rename d1/d11/a1 ..
abort: ../a1 not under root '$TESTTMP'
[255]
$ hg --config extensions.largefiles= rename d1/d11/a1 ..
The fsmonitor extension is incompatible with the largefiles extension and has been disabled. (fsmonitor !)
abort: ../a1 not under root '$TESTTMP'
[255]
$ hg status -C
$ mv d1/d11/a1 .hg
$ hg rename --after d1/d11/a1 .hg
abort: path contains illegal component: .hg/a1
[255]
$ hg status -C
! d1/d11/a1
$ hg update -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm .hg/a1
$ (cd d1/d11; hg rename ../../d2/b ../../.hg/foo)
abort: path contains illegal component: .hg/foo
[255]
$ hg status -C
$ (cd d1/d11; hg rename ../../d2/b ../../../foo)
abort: ../../../foo not under root '$TESTTMP'
[255]
$ hg status -C