view tests/test-merge2.t @ 29765:19578bb84731

extensions: add unwrapfunction to undo wrapfunction

Before this patch, we don't have a safe way to undo a wrapfunction because
other extensions may wrap the same function and calling setattr will undo
them accidentally.

This patch adds an "unwrapfunction" to address the issue. It removes the
wrapper from the wrapper chain, and re-wraps everything, which is not the
most efficient but short and easy to understand. We can revisit the code
if we have perf issues with long chains.

The "undo" feature is useful in cases like wrapping a function just in a
scope. Like, having a "select" command to interactively (using arrow keys)
select content from some output (ex. smartlog). It could wrap "ui.label" to
extract interesting texts just in the "select" command.

  $ hg init t
  $ cd t
  $ echo This is file a1 > a
  $ hg add a
  $ hg commit -m "commit #0"
  $ echo This is file b1 > b
  $ hg add b
  $ hg commit -m "commit #1"
  $ rm b
  $ hg update 0
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo This is file b2 > b
  $ hg add b
  $ hg commit -m "commit #2"
  created new head
  $ cd ..; rm -r t

  $ mkdir t
  $ cd t
  $ hg init
  $ echo This is file a1 > a
  $ hg add a
  $ hg commit -m "commit #0"
  $ echo This is file b1 > b
  $ hg add b
  $ hg commit -m "commit #1"
  $ rm b
  $ hg update 0
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo This is file b2 > b
  $ hg commit -A -m "commit #2"
  adding b
  created new head
  $ cd ..; rm -r t

  $ hg init t
  $ cd t
  $ echo This is file a1 > a
  $ hg add a
  $ hg commit -m "commit #0"
  $ echo This is file b1 > b
  $ hg add b
  $ hg commit -m "commit #1"
  $ rm b
  $ hg remove b
  $ hg update 0
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo This is file b2 > b
  $ hg commit -A -m "commit #2"
  adding b
  created new head

  $ cd ..