Improved ui.edit():
- Use descriptive name for temporary file: hg-editor-*.txt
- Don't import tempfile in the method, but use demandload()
- Remove tempfile file even if editor aborts.
%% no merges expected
%% merge should fail
abort: 'b' already exists in the working dir and differs from remote
%% merge of b expected
merging for b
merging b
%%
Contents of b should be "this is file b1"
This is file b1
%% merge fails
abort: outstanding uncommited changes
%% merge expected!
merging for b
merging b
%% merge of b should fail
abort: outstanding uncommited changes
%% merge of b expected
merging for b
merging b