tests/test-diff-change.t

wireprotov2: send linknodes to emitfilerevisions()

Previously, linknodes were calculated within emitfilerevisions() by
using filectx.introrev(), which would always use the linkrev/linknode
as recorded by storage. This is wrong for cases where the receiver
doesn't have the changeset the linknode refers to.

This commit changes the logic for linknode emission so the mapping
of filenode to linknode is computed by the caller and passed into
emitfilerevisions().

As part of the change, linknodes for "filesdata" in the
haveparents=False case are now correct: the existing code performed a
manifest walk and it was trivial to plug in the correct linknode.

However, behavior for the haveparents=True case is still wrong
because it relies on filtering linkrevs against the outgoing set in
order to determine what to send. This will be fixed in a subsequent
commit.

The change test test-wireproto-exchangev2-shallow.t is a bit wonky.
The test repo has 6 revisions. The changed test is performing a shallow
clone with depth=1. So, only file data for revision 5 is present
locally. So, the new behavior of associating the linknode with
revision 5 for every file revision seems correct. Of course, when
backfilling old revisions, we'll want to update the linknode. But
this problem requires wire protocol support and we'll cross that
bridge later.

Differential Revision: https://phab.mercurial-scm.org/D5405

Testing diff --change

  $ 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

  $ 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
  [255]

  $ 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

  $ cd ..