commands: use the new API to access hidden changesets in various commands In previous patches, we have added an internal API to unhide hidden changesets. This patch makes the following command use that api in nowarn mode i.e. there will be no warning while accessing hidden changesets. cat, diff, export, files, heads, identify, log, manifest, parents, status This patch also adds test demonstarting the behaviour. .. feature:: Accessing hidden changesets Set config option 'experimental.directaccess = True' to access hidden changesets from read only commands. Differential Revision: https://phab.mercurial-scm.org/D1735