config: explicitly track the use of the standard default value We introduce a small object used to detect that no specific default value has been passed to 'ui.config'. We need this explicit special value since "None" is a valid and common default value. The end goal here is to make progress on a centralised and explicit declaration of the available config option. A first good usecase for this are "default" value. Before starting looking further down this alley we needs to rework the handling of default value in the 'ui' object to have all configxyz methods going through the same logic. This is the first changeset on this trek.

clonebundle: update hook arguments (BC) By calling applybundle() with 'clonebundles' and the url instead of calling processbundle(), the hooks will get different arguments: HG_SOURCE will be 'clonebundles' instead of 'bundle2' and HG_URL will be the url instead of 'bundle2'. This is consistent with the bundle1 behavior and seems like a bug fix, but I'm marking it BC anyway.

commands: move checkconflict to bookmarks module Again, commands.bookmark is getting too large. checkconflict already has a lot of state and putting it in the bmstore makes more sense than having it as a closure. This also allows extensions a place to override this behavior. While we're here, add a documentation string because, well, we should be documenting more of our methods.

commands: move checkformat to bookmarks module commands.bookmark has grown quite large with two closures already. Let's split this up (and in the process allow extensions to override the default behavior).

tests: tell pip not to check for a newer version pip will check to see if it's the latest version, and complain if it isn't. The --no-index flag implies the --disable-pip-version-check flag, and makes the warning (and any associated network activity) go away.

changeset_templater: backport parts map of [templates] section from formatter

formatter: add support for parts map of [templates] section Unlike a mapfile whose template is looked up by spec -> mapfile -> topic, [templates] section is global. We use :sub-section syntax to define parts per template.

changeset_templater: backport separator template from formatter As commented, this should be used with docheader and docfooter, not with header nor footer. That's one reason why no props are passed to templater when rendering a separator. (See map-cmdline.changelog to understand what the "header" is.)

formatter: add support for separator template This seems useful for writing JSON template.

formatter: add support for docheader and docfooter templates templatepartsmap() is a minimal copy of changeset_templater.__init__(). I tried to factor out a common function, but it was unnecessarily complicated.