tests: fix various test-check-module-imports.t violations

Somehow these are only caught when running the test under Python 3.

Differential Revision: https://phab.mercurial-scm.org/D2580

tests/test-i18n.t

@@ -54,8 +54,8 b' tool itself by doctest'
 Check i18n cache isn't reused after encoding change:
 
   $ cat > $TESTTMP/encodingchange.py << EOF
+  > from mercurial.i18n import _
   > from mercurial import encoding, registrar
-  > from mercurial.i18n import _
   > cmdtable = {}
   > command = registrar.command(cmdtable)
   > @command(b'encodingchange', norepo=True)

tests/test-lfs.t

@@ -616,8 +616,8 b' enabled adds the lfs requirement'
   $ cat > $TESTTMP/dumpflog.py << EOF
   > # print raw revision sizes, flags, and hashes for certain files
   > import hashlib
+  > from mercurial.node import short
   > from mercurial import revlog
-  > from mercurial.node import short
   > def hash(rawtext):
   >     h = hashlib.sha512()
   >     h.update(rawtext)

tests/test-resolve.t

@@ -85,7 +85,12 b" don't allow marking or unmarking driver-"
 
   $ cat > $TESTTMP/markdriver.py << EOF
   > '''mark and unmark files as driver-resolved'''
-  > from mercurial import merge, registrar, scmutil, pycompat
+  > from mercurial import (
+  >    merge,
+  >    pycompat,
+  >    registrar,
+  >    scmutil,
+  > )
   > cmdtable = {}
   > command = registrar.command(cmdtable)
   > @command(b'markdriver',

tests/test-rollback.t

@@ -220,8 +220,8 b' I/O errors on stdio are handled properly'
   > import errno
   > from mercurial.i18n import _
   > from mercurial import (
+  >     error,
   >     registrar,
-  >     error,
   >     ui as uimod,
   > )
   > 

tests/test-split.t

@@ -2,7 +2,8 b''
 
   $ cat > $TESTTMP/editor.py <<EOF
   > #!$PYTHON
-  > import os, sys
+  > import os
+  > import sys
   > path = os.path.join(os.environ['TESTTMP'], 'messages')
   > messages = open(path).read().split('--\n')
   > prompt = open(sys.argv[1]).read()