diff --git a/contrib/debugshell.py b/contrib/debugshell.py
--- a/contrib/debugshell.py
+++ b/contrib/debugshell.py
@@ -56,7 +56,7 @@
         with demandimport.deactivated():
             __import__(pdbmap[debugger])
     except ImportError:
-        ui.warn(
+        ui.warnnoi18n(
             b"%s debugger specified but %s module was not found\n"
             % (debugger, pdbmap[debugger])
         )
diff --git a/contrib/perf.py b/contrib/perf.py
--- a/contrib/perf.py
+++ b/contrib/perf.py
@@ -1307,7 +1307,7 @@
             hint=b"see 'hg help config.paths'",
         )
     dest = path.pushloc or path.loc
-    ui.status(b'analysing phase of %s\n' % util.hidepassword(dest))
+    ui.statusnoi18n(b'analysing phase of %s\n' % util.hidepassword(dest))
     other = hg.peer(repo, opts, dest)
 
     # easier to perform discovery through the operation
@@ -1323,9 +1323,9 @@
     del other
     publishing = remotephases.get(b'publishing', False)
     if publishing:
-        ui.status(b'publishing: yes\n')
+        ui.statusnoi18n(b'publishing: yes\n')
     else:
-        ui.status(b'publishing: no\n')
+        ui.statusnoi18n(b'publishing: no\n')
 
     nodemap = repo.changelog.nodemap
     nonpublishroots = 0
@@ -1335,8 +1335,8 @@
         node = bin(nhex)
         if node in nodemap and int(phase):
             nonpublishroots += 1
-    ui.status(b'number of roots: %d\n' % len(remotephases))
-    ui.status(b'number of known non public roots: %d\n' % nonpublishroots)
+    ui.statusnoi18n(b'number of roots: %d\n' % len(remotephases))
+    ui.statusnoi18n(b'number of known non public roots: %d\n' % nonpublishroots)
 
     def d():
         phases.remotephasessummary(repo, remotesubset, remotephases)
@@ -3694,7 +3694,7 @@
 
     def write():
         for i in range(100000):
-            ui.write(b'Testing write performance\n')
+            ui.writenoi18n(b'Testing write performance\n')
 
     timer(write)
     fm.end()
diff --git a/doc/check-seclevel.py b/doc/check-seclevel.py
--- a/doc/check-seclevel.py
+++ b/doc/check-seclevel.py
@@ -47,7 +47,7 @@
 
 
 def checkseclevel(ui, doc, name, initlevel):
-    ui.note('checking "%s"\n' % name)
+    ui.notenoi18n('checking "%s"\n' % name)
     if not isinstance(doc, bytes):
         doc = doc.encode('utf-8')
     blocks, pruned = minirst.parse(doc, 0, ['verbose'])
@@ -70,11 +70,11 @@
             continue
         nextlevel = mark2level[mark]
         if curlevel < nextlevel and curlevel + 1 != nextlevel:
-            ui.warn('gap of section level at "%s" of %s\n' % (title, name))
+            ui.warnnoi18n('gap of section level at "%s" of %s\n' % (title, name))
             showavailables(ui, initlevel)
             errorcnt += 1
             continue
-        ui.note(
+        ui.notenoi18n(
             'appropriate section level for "%s %s"\n'
             % (mark * (nextlevel * 2), title)
         )
@@ -88,7 +88,7 @@
     for k, entry in cmdtable.items():
         name = k.split(b"|")[0].lstrip(b"^")
         if not entry[0].__doc__:
-            ui.note('skip checking %s: no help document\n' % (namefmt % name))
+            ui.notenoi18n('skip checking %s: no help document\n' % (namefmt % name))
             continue
         errorcnt += checkseclevel(
             ui, entry[0].__doc__, namefmt % name, initlevel
@@ -113,7 +113,7 @@
     ):
         mod = extensions.load(ui, name, None)
         if not mod.__doc__:
-            ui.note('skip checking %s extension: no help document\n' % name)
+            ui.notenoi18n('skip checking %s extension: no help document\n' % name)
             continue
         errorcnt += checkseclevel(
             ui, mod.__doc__, '%s extension' % name, initlevel_ext
@@ -138,7 +138,7 @@
         with open(filename) as fp:
             doc = fp.read()
 
-    ui.note(
+    ui.notenoi18n(
         'checking input from %s with initlevel %d\n' % (filename, initlevel)
     )
     return checkseclevel(ui, doc, 'input from %s' % filename, initlevel)
diff --git a/hgext/convert/cvsps.py b/hgext/convert/cvsps.py
--- a/hgext/convert/cvsps.py
+++ b/hgext/convert/cvsps.py
@@ -1021,7 +1021,7 @@
                 )
             )
             if cs.branchpoints:
-                ui.write(
+                ui.writenoi18n(
                     b'Branchpoints: %s \n' % b', '.join(sorted(cs.branchpoints))
                 )
             if opts[b"parents"] and cs.parents:
@@ -1044,9 +1044,9 @@
                 if r:
                     ui.write((b'Ancestors: %s\n' % (b','.join(r))))
 
-            ui.write(b'Log:\n')
+            ui.writenoi18n(b'Log:\n')
             ui.write(b'%s\n\n' % cs.comment)
-            ui.write(b'Members: \n')
+            ui.writenoi18n(b'Members: \n')
             for f in cs.entries:
                 fn = f.file
                 if fn.startswith(opts[b"prefix"]):
diff --git a/hgext/hgk.py b/hgext/hgk.py
--- a/hgext/hgk.py
+++ b/hgext/hgk.py
@@ -97,17 +97,17 @@
 
         for f in modified:
             # TODO get file permissions
-            ui.write(
+            ui.writenoi18n(
                 b":100664 100664 %s %s M\t%s\t%s\n"
                 % (short(mmap[f]), short(mmap2[f]), f, f)
             )
         for f in added:
-            ui.write(
+            ui.writenoi18n(
                 b":000000 100664 %s %s N\t%s\t%s\n"
                 % (empty, short(mmap2[f]), f, f)
             )
         for f in removed:
-            ui.write(
+            ui.writenoi18n(
                 b":100664 000000 %s %s D\t%s\t%s\n"
                 % (short(mmap[f]), empty, f, f)
             )
@@ -166,7 +166,7 @@
     ui.write((b"branch %s\n" % ctx.branch()))
     if obsolete.isenabled(repo, obsolete.createmarkersopt):
         if ctx.obsolete():
-            ui.write(b"obsolete\n")
+            ui.writenoi18n(b"obsolete\n")
     ui.write((b"phase %s\n\n" % ctx.phasestr()))
 
     if prefix != b"":
diff --git a/hgext/keyword.py b/hgext/keyword.py
--- a/hgext/keyword.py
+++ b/hgext/keyword.py
@@ -517,7 +517,7 @@
 
     uisetup(ui)
     reposetup(ui, repo)
-    ui.write(b'[extensions]\nkeyword =\n')
+    ui.writenoi18n(b'[extensions]\nkeyword =\n')
     demoitems(b'keyword', ui.configitems(b'keyword'))
     demoitems(b'keywordset', ui.configitems(b'keywordset'))
     demoitems(b'keywordmaps', kwmaps.iteritems())
diff --git a/hgext/phabricator.py b/hgext/phabricator.py
--- a/hgext/phabricator.py
+++ b/hgext/phabricator.py
@@ -774,7 +774,7 @@
                     try:
                         writediffproperties(unfi[newnode], diffmap[old.node()])
                     except util.urlerr.urlerror:
-                        ui.warn(b'Failed to update metadata for D%s\n' % drevid)
+                        ui.warnnoi18n(b'Failed to update metadata for D%s\n' % drevid)
                 # Remove local tags since it's no longer necessary
                 tagname = b'D%d' % drevid
                 if tagname in repo.tags():
diff --git a/hgext/remotefilelog/debugcommands.py b/hgext/remotefilelog/debugcommands.py
--- a/hgext/remotefilelog/debugcommands.py
+++ b/hgext/remotefilelog/debugcommands.py
@@ -187,7 +187,7 @@
 
     r = buildtemprevlog(repo, os.path.basename(file_)[:-2])
 
-    ui.write(b"digraph G {\n")
+    ui.writenoi18n(b"digraph G {\n")
     for i in r:
         node = r.node(i)
         pp = r.parents(node)
@@ -289,7 +289,7 @@
                 (b"smaller" if difference > 0 else b"bigger"),
             )
 
-            ui.write(
+            ui.writenoi18n(
                 b"Total:%s%s  %s (%s)\n"
                 % (
                     b"".ljust(2 * hashlen - len(b"Total:")),
diff --git a/hgext/show.py b/hgext/show.py
--- a/hgext/show.py
+++ b/hgext/show.py
@@ -316,7 +316,7 @@
             else:
                 ui.write(b'  ')
 
-            ui.write(b'o  ')
+            ui.writenoi18n(b'o  ')
             displayer.show(ctx, nodelen=nodelen)
             displayer.flush(ctx)
             ui.write(b'\n')
@@ -378,7 +378,7 @@
             ui.write(b' /   ')
 
         ui.write(_(b'(stack base)'), b'\n', label=b'stack.label')
-        ui.write(b'o  ')
+        ui.writenoi18n(b'o  ')
 
         displayer.show(basectx, nodelen=nodelen)
         displayer.flush(basectx)
diff --git a/hgext/win32mbcs.py b/hgext/win32mbcs.py
--- a/hgext/win32mbcs.py
+++ b/hgext/win32mbcs.py
@@ -215,4 +215,4 @@
         # command line options is not yet applied when
         # extensions.loadall() is called.
         if b'--debug' in sys.argv:
-            ui.write(b"[win32mbcs] activated with encoding: %s\n" % _encoding)
+            ui.writenoi18n(b"[win32mbcs] activated with encoding: %s\n" % _encoding)
diff --git a/mercurial/bundle2.py b/mercurial/bundle2.py
--- a/mercurial/bundle2.py
+++ b/mercurial/bundle2.py
@@ -2388,7 +2388,7 @@
     tr = op.gettransaction()
     markerdata = inpart.read()
     if op.ui.config(b'experimental', b'obsmarkers-exchange-debug'):
-        op.ui.write(
+        op.ui.writenoi18n(
             b'obsmarker-exchange: %i bytes received\n' % len(markerdata)
         )
     # The mergemarkers call will crash if marker creation is not enabled.
diff --git a/mercurial/debugcommands.py b/mercurial/debugcommands.py
--- a/mercurial/debugcommands.py
+++ b/mercurial/debugcommands.py
@@ -304,7 +304,7 @@
 def _debugchangegroup(ui, gen, all=None, indent=0, **opts):
     indent_string = b' ' * indent
     if all:
-        ui.write(
+        ui.writenoi18n(
             b"%sformat: id, p1, p2, cset, delta base, len(delta)\n"
             % indent_string
         )
@@ -438,12 +438,12 @@
     opts = pycompat.byteskwargs(opts)
     peer = hg.peer(ui, opts, path)
     caps = peer.capabilities()
-    ui.write(b'Main capabilities:\n')
+    ui.writenoi18n(b'Main capabilities:\n')
     for c in sorted(caps):
         ui.write(b'  %s\n' % c)
     b2caps = bundle2.bundle2caps(peer)
     if b2caps:
-        ui.write(b'Bundle2 capabilities:\n')
+        ui.writenoi18n(b'Bundle2 capabilities:\n')
         for key, values in sorted(b2caps.iteritems()):
             ui.write(b'  %s\n' % key)
             for v in values:
@@ -487,7 +487,7 @@
 )
 def debugcolor(ui, repo, **opts):
     """show available color, effects or style"""
-    ui.write(b'color mode: %s\n' % stringutil.pprint(ui._colormode))
+    ui.writenoi18n(b'color mode: %s\n' % stringutil.pprint(ui._colormode))
     if opts.get(r'style'):
         return _debugdisplaystyle(ui)
     else:
@@ -651,11 +651,11 @@
         d = dateutil.parsedate(date, util.extendeddateformats)
     else:
         d = dateutil.parsedate(date)
-    ui.write(b"internal: %d %d\n" % d)
-    ui.write(b"standard: %s\n" % dateutil.datestr(d))
+    ui.writenoi18n(b"internal: %d %d\n" % d)
+    ui.writenoi18n(b"standard: %s\n" % dateutil.datestr(d))
     if range:
         m = dateutil.matchdate(range)
-        ui.write(b"match: %s\n" % m(d[0]))
+        ui.writenoi18n(b"match: %s\n" % m(d[0]))
 
 
 @command(
@@ -922,7 +922,7 @@
             )
             common = set(common)
             if not opts.get(b'nonheads'):
-                ui.write(
+                ui.writenoi18n(
                     b"unpruned common: %s\n"
                     % b" ".join(sorted(short(n) for n in common))
                 )
@@ -969,24 +969,24 @@
     data[b'nb-revs-missing'] = data[b'nb-revs'] - data[b'nb-revs-common']
 
     # display discovery summary
-    ui.write(b"elapsed time:  %(elapsed)f seconds\n" % data)
-    ui.write(b"heads summary:\n")
-    ui.write(b"  total common heads:  %(nb-common)9d\n" % data)
-    ui.write(b"    also local heads:  %(nb-common-local)9d\n" % data)
-    ui.write(b"    also remote heads: %(nb-common-remote)9d\n" % data)
-    ui.write(b"    both:              %(nb-common-both)9d\n" % data)
-    ui.write(b"  local heads:         %(nb-local)9d\n" % data)
-    ui.write(b"    common:            %(nb-common-local)9d\n" % data)
-    ui.write(b"    missing:           %(nb-local-missing)9d\n" % data)
-    ui.write(b"  remote heads:        %(nb-remote)9d\n" % data)
-    ui.write(b"    common:            %(nb-common-remote)9d\n" % data)
-    ui.write(b"    unknown:           %(nb-remote-unknown)9d\n" % data)
-    ui.write(b"local changesets:      %(nb-revs)9d\n" % data)
-    ui.write(b"  common:              %(nb-revs-common)9d\n" % data)
-    ui.write(b"  missing:             %(nb-revs-missing)9d\n" % data)
+    ui.writenoi18n(b"elapsed time:  %(elapsed)f seconds\n" % data)
+    ui.writenoi18n(b"heads summary:\n")
+    ui.writenoi18n(b"  total common heads:  %(nb-common)9d\n" % data)
+    ui.writenoi18n(b"    also local heads:  %(nb-common-local)9d\n" % data)
+    ui.writenoi18n(b"    also remote heads: %(nb-common-remote)9d\n" % data)
+    ui.writenoi18n(b"    both:              %(nb-common-both)9d\n" % data)
+    ui.writenoi18n(b"  local heads:         %(nb-local)9d\n" % data)
+    ui.writenoi18n(b"    common:            %(nb-common-local)9d\n" % data)
+    ui.writenoi18n(b"    missing:           %(nb-local-missing)9d\n" % data)
+    ui.writenoi18n(b"  remote heads:        %(nb-remote)9d\n" % data)
+    ui.writenoi18n(b"    common:            %(nb-common-remote)9d\n" % data)
+    ui.writenoi18n(b"    unknown:           %(nb-remote-unknown)9d\n" % data)
+    ui.writenoi18n(b"local changesets:      %(nb-revs)9d\n" % data)
+    ui.writenoi18n(b"  common:              %(nb-revs-common)9d\n" % data)
+    ui.writenoi18n(b"  missing:             %(nb-revs-missing)9d\n" % data)
 
     if ui.verbose:
-        ui.write(
+        ui.writenoi18n(
             b"common heads: %s\n" % b" ".join(sorted(short(n) for n in common))
         )
 
@@ -1163,7 +1163,7 @@
 
     m = ctx.matchfileset(expr)
     if opts[b'show_matcher'] or (opts[b'show_matcher'] is None and ui.verbose):
-        ui.write(b'* matcher:\n', stringutil.prettyrepr(m), b'\n')
+        ui.writenoi18n(b'* matcher:\n', stringutil.prettyrepr(m), b'\n')
     for f in sorted(files):
         if not m(f):
             continue
@@ -1245,19 +1245,19 @@
 @command(b'debugfsinfo', [], _(b'[PATH]'), norepo=True)
 def debugfsinfo(ui, path=b"."):
     """show information detected about current filesystem"""
-    ui.write(b'path: %s\n' % path)
-    ui.write(b'mounted on: %s\n' % (util.getfsmountpoint(path) or b'(unknown)'))
-    ui.write(b'exec: %s\n' % (util.checkexec(path) and b'yes' or b'no'))
-    ui.write(b'fstype: %s\n' % (util.getfstype(path) or b'(unknown)'))
-    ui.write(b'symlink: %s\n' % (util.checklink(path) and b'yes' or b'no'))
-    ui.write(b'hardlink: %s\n' % (util.checknlink(path) and b'yes' or b'no'))
+    ui.writenoi18n(b'path: %s\n' % path)
+    ui.writenoi18n(b'mounted on: %s\n' % (util.getfsmountpoint(path) or b'(unknown)'))
+    ui.writenoi18n(b'exec: %s\n' % (util.checkexec(path) and b'yes' or b'no'))
+    ui.writenoi18n(b'fstype: %s\n' % (util.getfstype(path) or b'(unknown)'))
+    ui.writenoi18n(b'symlink: %s\n' % (util.checklink(path) and b'yes' or b'no'))
+    ui.writenoi18n(b'hardlink: %s\n' % (util.checknlink(path) and b'yes' or b'no'))
     casesensitive = b'(unknown)'
     try:
         with pycompat.namedtempfile(prefix=b'.debugfsinfo', dir=path) as f:
             casesensitive = util.fscasesensitive(f.name) and b'yes' or b'no'
     except OSError:
         pass
-    ui.write(b'case-sensitive: %s\n' % casesensitive)
+    ui.writenoi18n(b'case-sensitive: %s\n' % casesensitive)
 
 
 @command(
@@ -1409,7 +1409,7 @@
     """dump an index DAG as a graphviz dot file"""
     opts = pycompat.byteskwargs(opts)
     r = cmdutil.openstorage(repo, b'debugindexdot', file_, opts)
-    ui.write(b"digraph G {\n")
+    ui.writenoi18n(b"digraph G {\n")
     for i in r:
         node = r.node(i)
         pp = r.parents(node)
@@ -1818,13 +1818,13 @@
                             pid,
                             host,
                         )
-                ui.write(b"%-6s %s (%ds)\n" % (name + b":", locker, age))
+                ui.writenoi18n(b"%-6s %s (%ds)\n" % (name + b":", locker, age))
                 return 1
             except OSError as e:
                 if e.errno != errno.ENOENT:
                     raise
 
-        ui.write(b"%-6s free\n" % (name + b":"))
+        ui.writenoi18n(b"%-6s free\n" % (name + b":"))
         return 0
 
     held += report(repo.svfs, b"lock", repo.lock)
@@ -1920,7 +1920,7 @@
             return h
 
     def printrecords(version):
-        ui.write(b'* version %d records\n' % version)
+        ui.writenoi18n(b'* version %d records\n' % version)
         if version == 1:
             records = v1records
         else:
@@ -1929,12 +1929,12 @@
         for rtype, record in records:
             # pretty print some record types
             if rtype == b'L':
-                ui.write(b'local: %s\n' % record)
+                ui.writenoi18n(b'local: %s\n' % record)
             elif rtype == b'O':
-                ui.write(b'other: %s\n' % record)
+                ui.writenoi18n(b'other: %s\n' % record)
             elif rtype == b'm':
                 driver, mdstate = record.split(b'\0', 1)
-                ui.write(b'merge driver: %s (state "%s")\n' % (driver, mdstate))
+                ui.writenoi18n(b'merge driver: %s (state "%s")\n' % (driver, mdstate))
             elif rtype in b'FDC':
                 r = record.split(b'\0')
                 f, state, hash, lfile, afile, anode, ofile = r[0:7]
@@ -1943,16 +1943,16 @@
                     flags = r[7]
                 else:
                     onode, flags = r[7:9]
-                ui.write(
+                ui.writenoi18n(
                     b'file: %s (record type "%s", state "%s", hash %s)\n'
                     % (f, rtype, state, _hashornull(hash))
                 )
-                ui.write(b'  local path: %s (flags "%s")\n' % (lfile, flags))
-                ui.write(
+                ui.writenoi18n(b'  local path: %s (flags "%s")\n' % (lfile, flags))
+                ui.writenoi18n(
                     b'  ancestor path: %s (node %s)\n'
                     % (afile, _hashornull(anode))
                 )
-                ui.write(
+                ui.writenoi18n(
                     b'  other path: %s (node %s)\n'
                     % (ofile, _hashornull(onode))
                 )
@@ -1965,20 +1965,20 @@
                     extrastrings.append(b'%s = %s' % (extras[i], extras[i + 1]))
                     i += 2
 
-                ui.write(
+                ui.writenoi18n(
                     b'file extras: %s (%s)\n'
                     % (filename, b', '.join(extrastrings))
                 )
             elif rtype == b'l':
                 labels = record.split(b'\0', 2)
                 labels = [l for l in labels if len(l) > 0]
-                ui.write(b'labels:\n')
+                ui.writenoi18n(b'labels:\n')
                 ui.write((b'  local: %s\n' % labels[0]))
                 ui.write((b'  other: %s\n' % labels[1]))
                 if len(labels) > 2:
                     ui.write((b'  base:  %s\n' % labels[2]))
             else:
-                ui.write(
+                ui.writenoi18n(
                     b'unrecognized entry: %s\t%s\n'
                     % (rtype, record.replace(b'\0', b'\t'))
                 )
@@ -2004,15 +2004,15 @@
     v2records.sort(key=key)
 
     if not v1records and not v2records:
-        ui.write(b'no merge state found\n')
+        ui.writenoi18n(b'no merge state found\n')
     elif not v2records:
-        ui.note(b'no version 2 merge state\n')
+        ui.notenoi18n(b'no version 2 merge state\n')
         printrecords(1)
     elif ms._v1v2match(v1records, v2records):
-        ui.note(b'v1 and v2 states match: using v2\n')
+        ui.notenoi18n(b'v1 and v2 states match: using v2\n')
         printrecords(2)
     else:
-        ui.note(b'v1 and v2 states mismatch: using v1\n')
+        ui.notenoi18n(b'v1 and v2 states mismatch: using v1\n')
         printrecords(1)
         if ui.verbose:
             printrecords(2)
@@ -2381,15 +2381,15 @@
     overrides = {}
     if opts[b'tool']:
         overrides[(b'ui', b'forcemerge')] = opts[b'tool']
-        ui.note(b'with --tool %r\n' % (pycompat.bytestr(opts[b'tool'])))
+        ui.notenoi18n(b'with --tool %r\n' % (pycompat.bytestr(opts[b'tool'])))
 
     with ui.configoverride(overrides, b'debugmergepatterns'):
         hgmerge = encoding.environ.get(b"HGMERGE")
         if hgmerge is not None:
-            ui.note(b'with HGMERGE=%r\n' % (pycompat.bytestr(hgmerge)))
+            ui.notenoi18n(b'with HGMERGE=%r\n' % (pycompat.bytestr(hgmerge)))
         uimerge = ui.config(b"ui", b"merge")
         if uimerge:
-            ui.note(b'with ui.merge=%r\n' % (pycompat.bytestr(uimerge)))
+            ui.notenoi18n(b'with ui.merge=%r\n' % (pycompat.bytestr(uimerge)))
 
         ctx = scmutil.revsingle(repo, opts.get(b'rev'))
         m = scmutil.match(ctx, pats, opts)
@@ -2785,34 +2785,34 @@
         else:
             return value, 100.0
 
-    ui.write(b'format : %d\n' % format)
-    ui.write(b'flags  : %s\n' % b', '.join(flags))
+    ui.writenoi18n(b'format : %d\n' % format)
+    ui.writenoi18n(b'flags  : %s\n' % b', '.join(flags))
 
     ui.write(b'\n')
     fmt = pcfmtstr(totalsize)
     fmt2 = dfmtstr(totalsize)
-    ui.write(b'revisions     : ' + fmt2 % numrevs)
-    ui.write(b'    merges    : ' + fmt % pcfmt(nummerges, numrevs))
-    ui.write(b'    normal    : ' + fmt % pcfmt(numrevs - nummerges, numrevs))
-    ui.write(b'revisions     : ' + fmt2 % numrevs)
-    ui.write(b'    empty     : ' + fmt % pcfmt(numempty, numrevs))
-    ui.write(
+    ui.writenoi18n(b'revisions     : ' + fmt2 % numrevs)
+    ui.writenoi18n(b'    merges    : ' + fmt % pcfmt(nummerges, numrevs))
+    ui.writenoi18n(b'    normal    : ' + fmt % pcfmt(numrevs - nummerges, numrevs))
+    ui.writenoi18n(b'revisions     : ' + fmt2 % numrevs)
+    ui.writenoi18n(b'    empty     : ' + fmt % pcfmt(numempty, numrevs))
+    ui.writenoi18n(
         b'                   text  : '
         + fmt % pcfmt(numemptytext, numemptytext + numemptydelta)
     )
-    ui.write(
+    ui.writenoi18n(
         b'                   delta : '
         + fmt % pcfmt(numemptydelta, numemptytext + numemptydelta)
     )
-    ui.write(b'    snapshot  : ' + fmt % pcfmt(numfull + numsemi, numrevs))
+    ui.writenoi18n(b'    snapshot  : ' + fmt % pcfmt(numfull + numsemi, numrevs))
     for depth in sorted(numsnapdepth):
         ui.write(
             (b'      lvl-%-3d :       ' % depth)
             + fmt % pcfmt(numsnapdepth[depth], numrevs)
         )
-    ui.write(b'    deltas    : ' + fmt % pcfmt(numdeltas, numrevs))
-    ui.write(b'revision size : ' + fmt2 % totalsize)
-    ui.write(
+    ui.writenoi18n(b'    deltas    : ' + fmt % pcfmt(numdeltas, numrevs))
+    ui.writenoi18n(b'revision size : ' + fmt2 % totalsize)
+    ui.writenoi18n(
         b'    snapshot  : ' + fmt % pcfmt(fulltotal + semitotal, totalsize)
     )
     for depth in sorted(numsnapdepth):
@@ -2820,7 +2820,7 @@
             (b'      lvl-%-3d :       ' % depth)
             + fmt % pcfmt(snaptotal[depth], totalsize)
         )
-    ui.write(b'    deltas    : ' + fmt % pcfmt(deltatotal, totalsize))
+    ui.writenoi18n(b'    deltas    : ' + fmt % pcfmt(deltatotal, totalsize))
 
     def fmtchunktype(chunktype):
         if chunktype == b'empty':
@@ -2831,44 +2831,44 @@
             return b'    0x%s      : ' % hex(chunktype)
 
     ui.write(b'\n')
-    ui.write(b'chunks        : ' + fmt2 % numrevs)
+    ui.writenoi18n(b'chunks        : ' + fmt2 % numrevs)
     for chunktype in sorted(chunktypecounts):
         ui.write(fmtchunktype(chunktype))
         ui.write(fmt % pcfmt(chunktypecounts[chunktype], numrevs))
-    ui.write(b'chunks size   : ' + fmt2 % totalsize)
+    ui.writenoi18n(b'chunks size   : ' + fmt2 % totalsize)
     for chunktype in sorted(chunktypecounts):
         ui.write(fmtchunktype(chunktype))
         ui.write(fmt % pcfmt(chunktypesizes[chunktype], totalsize))
 
     ui.write(b'\n')
     fmt = dfmtstr(max(avgchainlen, maxchainlen, maxchainspan, compratio))
-    ui.write(b'avg chain length  : ' + fmt % avgchainlen)
-    ui.write(b'max chain length  : ' + fmt % maxchainlen)
-    ui.write(b'max chain reach   : ' + fmt % maxchainspan)
-    ui.write(b'compression ratio : ' + fmt % compratio)
+    ui.writenoi18n(b'avg chain length  : ' + fmt % avgchainlen)
+    ui.writenoi18n(b'max chain length  : ' + fmt % maxchainlen)
+    ui.writenoi18n(b'max chain reach   : ' + fmt % maxchainspan)
+    ui.writenoi18n(b'compression ratio : ' + fmt % compratio)
 
     if format > 0:
         ui.write(b'\n')
-        ui.write(
+        ui.writenoi18n(
             b'uncompressed data size (min/max/avg) : %d / %d / %d\n'
             % tuple(datasize)
         )
-    ui.write(
+    ui.writenoi18n(
         b'full revision size (min/max/avg)     : %d / %d / %d\n'
         % tuple(fullsize)
     )
-    ui.write(
+    ui.writenoi18n(
         b'inter-snapshot size (min/max/avg)    : %d / %d / %d\n'
         % tuple(semisize)
     )
     for depth in sorted(snapsizedepth):
         if depth == 0:
             continue
-        ui.write(
+        ui.writenoi18n(
             b'    level-%-3d (min/max/avg)          : %d / %d / %d\n'
             % ((depth,) + tuple(snapsizedepth[depth]))
         )
-    ui.write(
+    ui.writenoi18n(
         b'delta size (min/max/avg)             : %d / %d / %d\n'
         % tuple(deltasize)
     )
@@ -2877,21 +2877,21 @@
         ui.write(b'\n')
         fmt = pcfmtstr(numdeltas)
         fmt2 = pcfmtstr(numdeltas, 4)
-        ui.write(b'deltas against prev  : ' + fmt % pcfmt(numprev, numdeltas))
+        ui.writenoi18n(b'deltas against prev  : ' + fmt % pcfmt(numprev, numdeltas))
         if numprev > 0:
-            ui.write(
+            ui.writenoi18n(
                 b'    where prev = p1  : ' + fmt2 % pcfmt(nump1prev, numprev)
             )
-            ui.write(
+            ui.writenoi18n(
                 b'    where prev = p2  : ' + fmt2 % pcfmt(nump2prev, numprev)
             )
-            ui.write(
+            ui.writenoi18n(
                 b'    other            : ' + fmt2 % pcfmt(numoprev, numprev)
             )
         if gdelta:
-            ui.write(b'deltas against p1    : ' + fmt % pcfmt(nump1, numdeltas))
-            ui.write(b'deltas against p2    : ' + fmt % pcfmt(nump2, numdeltas))
-            ui.write(
+            ui.writenoi18n(b'deltas against p1    : ' + fmt % pcfmt(nump1, numdeltas))
+            ui.writenoi18n(b'deltas against p2    : ' + fmt % pcfmt(nump2, numdeltas))
+            ui.writenoi18n(
                 b'deltas against other : ' + fmt % pcfmt(numother, numdeltas)
             )
 
@@ -2929,7 +2929,7 @@
                 % (b"nodeid".ljust(idlen), b"p1".ljust(idlen))
             )
         else:
-            ui.write(
+            ui.writenoi18n(
                 b"   rev linkrev %s %s p2\n"
                 % (b"nodeid".ljust(idlen), b"p1".ljust(idlen))
             )
@@ -2943,7 +2943,7 @@
                 % b"nodeid".rjust(idlen)
             )
         else:
-            ui.write(
+            ui.writenoi18n(
                 b"   rev flag     size   link     p1     p2 %s\n"
                 % b"nodeid".rjust(idlen)
             )
@@ -3109,14 +3109,14 @@
         arevs = revset.makematcher(treebystage[b'analyzed'])(repo)
         brevs = revset.makematcher(treebystage[b'optimized'])(repo)
         if opts[b'show_set'] or (opts[b'show_set'] is None and ui.verbose):
-            ui.write(b"* analyzed set:\n", stringutil.prettyrepr(arevs), b"\n")
-            ui.write(b"* optimized set:\n", stringutil.prettyrepr(brevs), b"\n")
+            ui.writenoi18n(b"* analyzed set:\n", stringutil.prettyrepr(arevs), b"\n")
+            ui.writenoi18n(b"* optimized set:\n", stringutil.prettyrepr(brevs), b"\n")
         arevs = list(arevs)
         brevs = list(brevs)
         if arevs == brevs:
             return 0
-        ui.write(b'--- analyzed\n', label=b'diff.file_a')
-        ui.write(b'+++ optimized\n', label=b'diff.file_b')
+        ui.writenoi18n(b'--- analyzed\n', label=b'diff.file_a')
+        ui.writenoi18n(b'+++ optimized\n', label=b'diff.file_b')
         sm = difflib.SequenceMatcher(None, arevs, brevs)
         for tag, alo, ahi, blo, bhi in sm.get_opcodes():
             if tag in (r'delete', r'replace'):
@@ -3133,7 +3133,7 @@
     func = revset.makematcher(tree)
     revs = func(repo)
     if opts[b'show_set'] or (opts[b'show_set'] is None and ui.verbose):
-        ui.write(b"* set:\n", stringutil.prettyrepr(revs), b"\n")
+        ui.writenoi18n(b"* set:\n", stringutil.prettyrepr(revs), b"\n")
     if not opts[b'show_revs']:
         return
     for c in revs:
@@ -3311,9 +3311,9 @@
 def debugsub(ui, repo, rev=None):
     ctx = scmutil.revsingle(repo, rev, None)
     for k, v in sorted(ctx.substate.items()):
-        ui.write(b'path %s\n' % k)
-        ui.write(b' source   %s\n' % v[0])
-        ui.write(b' revision %s\n' % v[1])
+        ui.writenoi18n(b'path %s\n' % k)
+        ui.writenoi18n(b' source   %s\n' % v[0])
+        ui.writenoi18n(b' revision %s\n' % v[1])
 
 
 @command(
@@ -3414,22 +3414,22 @@
         ui.note(templater.prettyformat(tree), b'\n')
         newtree = templater.expandaliases(tree, aliases)
         if newtree != tree:
-            ui.note(b"* expanded:\n", templater.prettyformat(newtree), b'\n')
+            ui.notenoi18n(b"* expanded:\n", templater.prettyformat(newtree), b'\n')
 
     if revs is None:
         tres = formatter.templateresources(ui, repo)
         t = formatter.maketemplater(ui, tmpl, resources=tres)
         if ui.verbose:
             kwds, funcs = t.symbolsuseddefault()
-            ui.write(b"* keywords: %s\n" % b', '.join(sorted(kwds)))
-            ui.write(b"* functions: %s\n" % b', '.join(sorted(funcs)))
+            ui.writenoi18n(b"* keywords: %s\n" % b', '.join(sorted(kwds)))
+            ui.writenoi18n(b"* functions: %s\n" % b', '.join(sorted(funcs)))
         ui.write(t.renderdefault(props))
     else:
         displayer = logcmdutil.maketemplater(ui, repo, tmpl)
         if ui.verbose:
             kwds, funcs = displayer.t.symbolsuseddefault()
-            ui.write(b"* keywords: %s\n" % b', '.join(sorted(kwds)))
-            ui.write(b"* functions: %s\n" % b', '.join(sorted(funcs)))
+            ui.writenoi18n(b"* keywords: %s\n" % b', '.join(sorted(kwds)))
+            ui.writenoi18n(b"* functions: %s\n" % b', '.join(sorted(funcs)))
         for r in revs:
             displayer.show(repo[r], **pycompat.strkwargs(props))
         displayer.close()
@@ -3444,7 +3444,7 @@
 def debuguigetpass(ui, prompt=b''):
     """show prompt to type password"""
     r = ui.getpass(prompt)
-    ui.write(b'respose: %s\n' % r)
+    ui.writenoi18n(b'respose: %s\n' % r)
 
 
 @command(
@@ -3456,7 +3456,7 @@
 def debuguiprompt(ui, prompt=b''):
     """show plain prompt"""
     r = ui.prompt(prompt)
-    ui.write(b'response: %s\n' % r)
+    ui.writenoi18n(b'response: %s\n' % r)
 
 
 @command(b'debugupdatecaches', [])
@@ -3522,7 +3522,7 @@
     opts = pycompat.byteskwargs(opts)
     m = scmutil.match(repo[None], pats, opts)
     if ui.verbose:
-        ui.write(b'* matcher:\n', stringutil.prettyrepr(m), b'\n')
+        ui.writenoi18n(b'* matcher:\n', stringutil.prettyrepr(m), b'\n')
     items = list(repo[None].walk(m))
     if not items:
         return
diff --git a/mercurial/dispatch.py b/mercurial/dispatch.py
--- a/mercurial/dispatch.py
+++ b/mercurial/dispatch.py
@@ -93,7 +93,7 @@
                 except:  # re-raises below
                     if exc is None:
                         exc = sys.exc_info()[1]
-                    self.ui.warn(b'error in exit handlers:\n')
+                    self.ui.warnnoi18n(b'error in exit handlers:\n')
                     self.ui.traceback(force=True)
         finally:
             if exc is not None:
diff --git a/mercurial/sslutil.py b/mercurial/sslutil.py
--- a/mercurial/sslutil.py
+++ b/mercurial/sslutil.py
@@ -383,11 +383,11 @@
             sslkeylog.set_keylog(
                 pycompat.fsdecode(encoding.environ[b'SSLKEYLOGFILE'])
             )
-            ui.warn(
+            ui.warnnoi18n(
                 b'sslkeylog enabled by SSLKEYLOGFILE environment variable\n'
             )
         except ImportError:
-            ui.warn(
+            ui.warnnoi18n(
                 b'sslkeylog module missing, '
                 b'but SSLKEYLOGFILE set in environment\n'
             )
diff --git a/tests/blackbox-readonly-dispatch.py b/tests/blackbox-readonly-dispatch.py
--- a/tests/blackbox-readonly-dispatch.py
+++ b/tests/blackbox-readonly-dispatch.py
@@ -14,10 +14,10 @@
     """
     ui = uimod.ui.load()
     extensions.populateui(ui)
-    ui.status(b"running: %s\n" % cmd)
+    ui.statusnoi18n(b"running: %s\n" % cmd)
     req = dispatch.request(cmd.split(), ui)
     result = dispatch.dispatch(req)
-    ui.status(b"result: %r\n" % result)
+    ui.statusnoi18n(b"result: %r\n" % result)
 
 
 # create file 'foo', add and commit
diff --git a/tests/test-ui-color.py b/tests/test-ui-color.py
--- a/tests/test-ui-color.py
+++ b/tests/test-ui-color.py
@@ -10,8 +10,8 @@
 # ensure errors aren't buffered
 testui = uimod.ui()
 testui.pushbuffer()
-testui.write(b'buffered\n')
-testui.warn(b'warning\n')
+testui.writenoi18n(b'buffered\n')
+testui.warnnoi18n(b'warning\n')
 testui.write_err(b'error\n')
 print(stringutil.pprint(testui.popbuffer(), bprefix=True).decode('ascii'))