tests/test-patch-offset.t
author Pierre-Yves David <pierre-yves.david@octobus.net>
Mon, 11 Dec 2023 22:27:59 +0100
changeset 51181 dcaa2df1f688
parent 41738 c70bdd222dcd
permissions -rw-r--r--
changelog: never inline changelog The test suite mostly use small repositories, that implies that most changelog in the tests are inlined. As a result, non-inlined changelog are quite poorly tested. Since non-inline changelog are most common case for serious repositories, this lack of testing is a significant problem that results in high profile issue like the one recently fixed by 66417f55ea33 and 849745d7da89. Inlining the changelog does not bring much to the table, the number of total file saved is negligible, and the changelog will be read by most operation anyway. So this changeset is make it so we never inline the changelog, and de-inline the one that are still inlined whenever we touch them. By doing that, we remove the "dual code path" situation for writing new entry to the changelog and move to a "single code path" situation. Having a single code path simplify the code and make sure it is covered by test (if test cover that situation obviously) This impact all tests that care about the number of file and the exchange size, but there is nothing too complicated in them just a lot of churn. The churn is made "worse" by the fact rust will use the persistent nodemap on any changelog now. Which is overall a win as it means testing the persistent nodemap more and having less special cases. In short, having inline changelog is mostly useless and an endless source of pain. We get rid of it.


  $ cat > writepatterns.py <<EOF
  > import sys
  > 
  > path = sys.argv[1]
  > patterns = sys.argv[2:]
  > 
  > fp = open(path, 'wb')
  > for pattern in patterns:
  >     count = int(pattern[0:-1])
  >     char = pattern[-1].encode('utf8') + b'\n'
  >     fp.write(char * count)
  > fp.close()
  > EOF

prepare repo

  $ hg init a
  $ cd a

These initial lines of Xs were not in the original file used to generate
the patch.  So all the patch hunks need to be applied to a constant offset
within this file.  If the offset isn't tracked then the hunks can be
applied to the wrong lines of this file.

  $ "$PYTHON" ../writepatterns.py a 34X 10A 1B 10A 1C 10A 1B 10A 1D 10A 1B 10A 1E 10A 1B 10A
  $ hg commit -Am adda
  adding a

This is a cleaner patch generated via diff
In this case it reproduces the problem when
the output of hg export does not
import patch

  $ hg import -v -m 'b' -d '2 0' - <<EOF
  > --- a/a	2009-12-08 19:26:17.000000000 -0800
  > +++ b/a	2009-12-08 19:26:17.000000000 -0800
  > @@ -9,7 +9,7 @@
  >  A
  >  A
  >  B
  > -A
  > +a
  >  A
  >  A
  >  A
  > @@ -53,7 +53,7 @@
  >  A
  >  A
  >  B
  > -A
  > +a
  >  A
  >  A
  >  A
  > @@ -75,7 +75,7 @@
  >  A
  >  A
  >  B
  > -A
  > +a
  >  A
  >  A
  >  A
  > EOF
  applying patch from stdin
  patching file a
  Hunk #1 succeeded at 43 (offset 34 lines).
  Hunk #2 succeeded at 87 (offset 34 lines).
  Hunk #3 succeeded at 109 (offset 34 lines).
  committing files:
  a
  committing manifest
  committing changelog
  created 189885cecb41

compare imported changes against reference file

  $ "$PYTHON" ../writepatterns.py aref 34X 10A 1B 1a 9A 1C 10A 1B 10A 1D 10A 1B 1a 9A 1E 10A 1B 1a 9A
  $ diff aref a

  $ cd ..