view tests/test-rhg-no-generaldelta.t @ 49788:31b4675ca998 stable

emitrevision: if we need to compute a delta on the fly, try p1 or p2 first

Falling back to `prev` does not yield any real value on modern storage and
result in pathological changes to be created on the other side. Doing a delta
against a parent will likely be smaller (helping the network) and will be safer
to apply on the client (helping future pulls by Triggering intermediate
snapshop where they will be needed by later deltas).

  $ NO_FALLBACK="env RHG_ON_UNSUPPORTED=abort"

  $ cat << EOF >> $HGRCPATH
  > [format]
  > sparse-revlog = no
  > EOF

  $ hg init repo --config format.generaldelta=no --config format.usegeneraldelta=no
  $ cd repo
  $ (echo header; seq.py 20) > f
  $ hg commit -q -Am initial
  $ (echo header; seq.py 20; echo footer) > f
  $ hg commit -q -Am x
  $ hg update ".^"
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ (seq.py 20; echo footer) > f
  $ hg commit -q -Am y
  $ hg debugdeltachain f --template '{rev} {prevrev} {deltatype}\n'
  0 -1 base
  1 0 prev
  2 1 prev

rhg works on non-generaldelta revlogs:

  $ $NO_FALLBACK hg cat f -r .
  1
  2
  3
  4
  5
  6
  7
  8
  9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  footer