help: add internals.extensions topic
I think it's better to include the API overview in core as we now have the
internals section in our help system.
Retrieved from the wiki, and formatted as reST. Several wiki links are
removed since they are invalid in the help. The sections about example
extension are removed at all as they seemed too verbose.
https://www.mercurial-scm.org/wiki/WritingExtensions
Initial setup.
$ hg init repo
$ cd repo
$ touch thefile
$ hg ci -A -m 'Initial commit.'
adding thefile
Create a tag.
$ hg tag branchortag
Create a branch with the same name as the tag.
$ hg branch branchortag
marked working directory as branch branchortag
(branches are permanent and global, did you want a bookmark?)
$ hg ci -m 'Create a branch with the same name as a tag.'
This is what we have:
$ hg log
changeset: 2:10519b3f489a
branch: branchortag
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Create a branch with the same name as a tag.
changeset: 1:2635c45ca99b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Added tag branchortag for changeset f57387372b5d
changeset: 0:f57387372b5d
tag: branchortag
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit.
Update to the tag:
$ hg up 'tag(branchortag)'
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg parents
changeset: 0:f57387372b5d
tag: branchortag
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit.
Updating to the branch:
$ hg up 'branch(branchortag)'
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 2:10519b3f489a
branch: branchortag
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Create a branch with the same name as a tag.
$ cd ..