copy: distinguish "file exists" cases and add a hint (BC)
Users that want to add a copy record to an existing commit with 'hg
commit --amend' should be guided towards this workflow, rather than
reaching for some sort of uncommit-recommit flow. As part of this,
distinguish in the top-line error message whether the file merely
already exists (untracked) on disk or the file already exists in
history.
The full list of copy and rename cases and how they interact with
flags are listed below:
target exists --after --force | action
n n * | copy
n y * | (1)
untracked n n | (4) NEWHINT
untracked n y | (3)
untracked y * | (2)
y n n | (4) NEWHINT
y n y | (3)
y y n | (2)
y y y | (3)
deleted n n | copy
deleted n y | (3)
deleted y n | (1)
deleted y y | (1)
* = don't care
(1) <src>: not recording move - <target> does not exist
(2) preserve target contents
(3) replace target contents
(4) <target>: not overwriting - file {exists,already committed}
Credit to Kevin for wholly rewriting my table to cover more cases we
discovered at the sprint.
I think this change gets the hints correct in all cases, but I'd
appreciate close inspection of the test cases to make sure I haven't
gotten turned around in here.
# See http://EditorConfig.org for the specification
root = true
[*.py]
indent_size = 4
indent_style = space
trim_trailing_whitespace = true
[*.{c,h}]
indent_size = 8
indent_style = tab
trim_trailing_whitespace = true