diff mercurial/logcmdutil.py @ 47437:7a430116f639

ui: add a context manager for silencing the ui (pushbuffer+popbuffer)

We often silence the ui by calling `ui.pushbuffer()` followed (a later
in the code) by `ui.popbuffer()`. These places can be identified by
the fact that they ignore the output returned from
`ui.popbuffer()`. Let's create a context manager for these cases, to
avoid repetition, and to avoid accidentally leaving the ui silent on
exceptions. I deliberately called the new function `silent()` instead
of `buffered()`, because it's just an implementation detail that it
uses `pushbuffer()` and `popbuffer()`. We could later optimize it to
not buffer the output.

Differential Revision: https://phab.mercurial-scm.org/D10884

--- a/mercurial/logcmdutil.py	Fri Jun 18 14:17:43 2021 -0700
+++ b/mercurial/logcmdutil.py	Fri Jun 18 15:48:51 2021 -0700
@@ -93,9 +93,8 @@
             },
             b"merge-diff",
         ):
-            repo.ui.pushbuffer()
-            merge.merge(ctx.p2(), wc=wctx)
-            repo.ui.popbuffer()
+            with repo.ui.silent():
+                merge.merge(ctx.p2(), wc=wctx)
         return wctx
     else:
         return ctx.p1()