errors: introduce InputError and use it from commands and cmdutil This patch introduces a `InputError` class and replaces many uses of `error.Abort` by it in `commands` and `cmdutil`. This is a part of https://www.mercurial-scm.org/wiki/ErrorCategoriesPlan. There will later be a different class for state errors (to raise e.g. when there's an unfinished operation). It's not always clear when one should report an input error and when it should be a state error. We can always adjust later if I got something wrong in this patch (but feel free to point out any you notice now). Differential Revision: https://phab.mercurial-scm.org/D9167

--- a/mercurial/scmutil.py	Wed Oct 21 19:00:16 2020 -0700
+++ b/mercurial/scmutil.py	Tue Oct 06 22:36:15 2020 -0700
@@ -219,6 +219,8 @@
     except error.WdirUnsupported:
         ui.error(_(b"abort: working directory revision cannot be specified\n"))
     except error.Abort as inst:
+        if isinstance(inst, error.InputError):
+            detailed_exit_code = 10
         ui.error(_(b"abort: %s\n") % inst.message)
         if inst.hint:
             ui.error(_(b"(%s)\n") % inst.hint)