Mercurial > hg
view tests/test-diffstat.t @ 46607:e9901d01d135
revlog: add a mechanism to verify expected file position before appending
If someone uses `hg debuglocks`, or some non-hg process writes to the .hg
directory without respecting the locks, or if the repo's on a networked
filesystem, it's possible for the revlog code to write out corrupted data.
The form of this corruption can vary depending on what data was written and how
that happened. We are in the "networked filesystem" case (though I've had users
also do this to themselves with the "`hg debuglocks`" scenario), and most often
see this with the changelog. What ends up happening is we produce two items
(let's call them rev1 and rev2) in the .i file that have the same linkrev,
baserev, and offset into the .d file, while the data in the .d file is appended
properly. rev2's compressed_size is accurate for rev2, but when we go to
decompress the data in the .d file, we use the offset that's recorded in the
index file, which is the same as rev1, and attempt to decompress
rev2.compressed_size bytes of rev1's data. This usually does not succeed. :)
When using inline data, this also fails, though I haven't investigated why too
closely. This shows up as a "patch decode" error. I believe what's happening
there is that we're basically ignoring the offset field, getting the data
properly, but since baserev != rev, it thinks this is a delta based on rev
(instead of a full text) and can't actually apply it as such.
For now, I'm going to make this an optional component and default it to entirely
off. I may increase the default severity of this in the future, once I've
enabled it for my users and we gain more experience with it. Luckily, most of my
users have a versioned filesystem and can roll back to before the corruption has
been written, it's just a hassle to do so and not everyone knows how (so it's a
support burden). Users on other filesystems will not have that luxury, and this
can cause them to have a corrupted repository that they are unlikely to know how
to resolve, and they'll see this as a data-loss event. Refusing to create the
corruption is a much better user experience.
This mechanism is not perfect. There may be false-negatives (racy writes that
are not detected). There should not be any false-positives (non-racy writes that
are detected as such). This is not a mechanism that makes putting a repo on a
networked filesystem "safe" or "supported", just *less* likely to cause
corruption.
Differential Revision: https://phab.mercurial-scm.org/D9952
author | Kyle Lippincott <spectral@google.com> |
---|---|
date | Wed, 03 Feb 2021 16:33:10 -0800 |
parents | 251332dbf33d |
children | 0492002560f3 |
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$ hg init repo $ cd repo $ i=0; while [ "$i" -lt 213 ]; do echo a >> a; i=`expr $i + 1`; done $ hg add a $ cp a b $ hg add b Wide diffstat: $ hg diff --stat a | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ b | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 426 insertions(+), 0 deletions(-) diffstat width: $ COLUMNS=24 hg diff --config ui.interactive=true --stat a | 213 ++++++++++++++ b | 213 ++++++++++++++ 2 files changed, 426 insertions(+), 0 deletions(-) $ hg ci -m adda $ cat >> a <<EOF > a > a > a > EOF Narrow diffstat: $ hg diff --stat a | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) $ hg ci -m appenda >>> open("c", "wb").write(b"\0") and None $ touch d $ hg add c d Binary diffstat: $ hg diff --stat c | Bin 1 files changed, 0 insertions(+), 0 deletions(-) Binary git diffstat: $ hg diff --stat --git c | Bin d | 0 2 files changed, 0 insertions(+), 0 deletions(-) $ hg ci -m createb >>> open("file with spaces", "wb").write(b"\0") and None $ hg add "file with spaces" Filename with spaces diffstat: $ hg diff --stat file with spaces | Bin 1 files changed, 0 insertions(+), 0 deletions(-) Filename with spaces git diffstat: $ hg diff --stat --git file with spaces | Bin 1 files changed, 0 insertions(+), 0 deletions(-) Filename without "a/" or "b/" (issue5759): $ hg diff --config 'diff.noprefix=1' -c1 --stat --git a | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) $ hg diff --config 'diff.noprefix=1' -c2 --stat --git c | Bin d | 0 2 files changed, 0 insertions(+), 0 deletions(-) $ hg log --config 'diff.noprefix=1' -r '1:' -p --stat --git changeset: 1:3a95b07bb77f user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: appenda a | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a a --- a +++ a @@ -211,3 +211,6 @@ a a a +a +a +a changeset: 2:c60a6c753773 tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: createb c | Bin d | 0 2 files changed, 0 insertions(+), 0 deletions(-) diff --git c c new file mode 100644 index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..f76dd238ade08917e6712764a16a22005a50573d GIT binary patch literal 1 Ic${MZ000310RR91 diff --git d d new file mode 100644 diffstat within directories: $ hg rm -f 'file with spaces' $ mkdir dir1 dir2 $ echo new1 > dir1/new $ echo new2 > dir2/new $ hg add dir1/new dir2/new $ hg diff --stat dir1/new | 1 + dir2/new | 1 + 2 files changed, 2 insertions(+), 0 deletions(-) $ hg diff --stat --root dir1 new | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) $ hg diff --stat --root dir1 dir2 warning: dir2 not inside relative root dir1 $ hg diff --stat --root dir1 -I dir1/old $ cd dir1 $ hg diff --stat . dir1/new | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) $ hg diff --stat . --config ui.relative-paths=yes new | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) $ hg diff --stat --root . new | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) $ hg diff --stat --root . --config ui.relative-paths=yes new | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) --root trumps ui.relative-paths $ hg diff --stat --root .. --config ui.relative-paths=yes new | 1 + ../dir2/new | 1 + 2 files changed, 2 insertions(+), 0 deletions(-) $ hg diff --stat --root ../dir1 ../dir2 warning: ../dir2 not inside relative root . $ hg diff --stat --root . -I old $ cd .. Files with lines beginning with '--' or '++' should be properly counted in diffstat $ hg up -Cr tip 0 files updated, 0 files merged, 0 files removed, 0 files unresolved $ rm dir1/new $ rm dir2/new $ rm "file with spaces" $ cat > file << EOF > line 1 > line 2 > line 3 > EOF $ hg commit -Am file adding file Lines added starting with '--' should count as additions $ cat > file << EOF > line 1 > -- line 2, with dashes > line 3 > EOF $ hg diff --root . diff -r be1569354b24 file --- a/file Thu Jan 01 00:00:00 1970 +0000 +++ b/file * (glob) @@ -1,3 +1,3 @@ line 1 -line 2 +-- line 2, with dashes line 3 $ hg diff --root . --stat file | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) Lines changed starting with '--' should count as deletions $ hg commit -m filev2 $ cat > file << EOF > line 1 > -- line 2, with dashes, changed again > line 3 > EOF $ hg diff --root . diff -r 160f7c034df6 file --- a/file Thu Jan 01 00:00:00 1970 +0000 +++ b/file * (glob) @@ -1,3 +1,3 @@ line 1 --- line 2, with dashes +-- line 2, with dashes, changed again line 3 $ hg diff --root . --stat file | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) Lines changed starting with '--' should count as deletions and starting with '++' should count as additions $ cat > file << EOF > line 1 > ++ line 2, switched dashes to plusses > line 3 > EOF $ hg diff --root . diff -r 160f7c034df6 file --- a/file Thu Jan 01 00:00:00 1970 +0000 +++ b/file * (glob) @@ -1,3 +1,3 @@ line 1 --- line 2, with dashes +++ line 2, switched dashes to plusses line 3 $ hg diff --root . --stat file | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) When a file is renamed, --git shouldn't loss the info about old file $ hg init issue6025 $ cd issue6025 $ echo > a $ hg ci -Am 'add a' adding a $ hg mv a b $ hg diff --git diff --git a/a b/b rename from a rename to b $ hg diff --stat a | 1 - b | 1 + 2 files changed, 1 insertions(+), 1 deletions(-) $ hg diff --stat --git a => b | 0 1 files changed, 0 insertions(+), 0 deletions(-) -- filename may contain whitespaces $ echo > c $ hg ci -Am 'add c' adding c $ hg mv c 'new c' $ hg diff --git diff --git a/c b/new c rename from c rename to new c $ hg diff --stat c | 1 - new c | 1 + 2 files changed, 1 insertions(+), 1 deletions(-) $ hg diff --stat --git c => new c | 0 1 files changed, 0 insertions(+), 0 deletions(-) Make sure `diff --stat -q --config diff.git-0` shows stat (issue4037) $ hg status A new c R c $ hg diff --stat -q c | 1 - new c | 1 + 2 files changed, 1 insertions(+), 1 deletions(-)