purge: move extension into core mercurial The motivation is simple: it's nicer to avoid gating basic functionality. To reduce the risk of people shooting themselves in the feet, `--confirm` is now the default, unless the extensions is loaded.. For review of the body of the purge command, use this instead of what hg/phabricator will show (the block of code is modified, not just moved): Differential Revision: https://phab.mercurial-scm.org/D9820

--- a/tests/test-hgweb-json.t	Mon Jan 18 10:24:11 2021 +0100
+++ b/tests/test-hgweb-json.t	Mon Jan 18 10:24:20 2021 +0100
@@ -2190,6 +2190,10 @@
         "topic": "phase"
       },
       {
+        "summary": "removes files not tracked by Mercurial",
+        "topic": "purge"
+      },
+      {
         "summary": "roll back an interrupted transaction",
         "topic": "recover"
       },