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mergemercurialdvcsmerge-conflict-resolution

Mercurial show diff against 2 parents or base during merge

Our teem recently faced with merge that removes one leaf of merge and we "lost" changes (as if you perform hg merge --tool internal:local).

This happen because we don't experienced with hg merge command.

hg diff shown only one difference, but not other.

BASE --- HEAD1 --- MERGE
   \---- HEAD2 --/

Suppose in HEAD1 I merge HEAD2 but has not yet commit changes.

HEAD2 diff against MERGE I see by hg diff. It is -r BASE:HEAD2 patch.

How can I see diff between current local merge state with HEAD1 as if we merge from HEAD2

How can I see diff between current local merge state with BASE?

Solution

  • Thanks @Vince for suggestion. I reread hg help diff and hg help revset and get that I want.

    Assume that you at MERGE before commit and perform merge from HEAD1.

    To compare diff against HEAD1 use one of:

    hg diff
hg diff -r .
hg diff -r HEAD1

    Check:

     hg log -r .

    To compare diff against HEAD1 use one of:

    hg diff -r HEAD2

    If you have only 2 heads in current branch last expression can be written without HEAD2 name:

    hg diff -r 'branch(.) & head() - .'

    Check:

    hg log -r 'branch(.) & head() - .'

    To compare against BASE:

    hg log -r 'ancestor(HEAD1, HEAD2)'

    If you have only 2 heads in current branch last expression can be written without HEAD1/HEAD2 names::

    hg diff -r 'ancestor(branch(.) & head())'

    Check:

    hg log -r 'ancestor(branch(.) & head())'

    I wander if there are any shortcut for second parent of current merge. For first - just dot sign...

    UPDATE Hm... p1() and p2() are awesome! I rewrote my examples in way that they have no concrete names HEAD1/HEAD2:

    hg diff -r 'p1()'
hg diff -r 'p2()'
hg diff -r 'ancestor(p1(), p2())'