diff --git a/contrib/check-code.py b/contrib/check-code.py
--- a/contrib/check-code.py
+++ b/contrib/check-code.py
@@ -337,6 +337,8 @@ pypats = [
     (r'^import httplib', "don't use httplib, use util.httplib"),
     (r'^import BaseHTTPServer', "use util.httpserver instead"),
     (r'\.next\(\)', "don't use .next(), use next(...)"),
+    (r'([a-z]*).revision\(\1\.node\(',
+     "don't covert rev to node before passing to revision(nodeorrev)"),
 
     # rules depending on implementation of repquote()
     (r' x+[xpqo%APM][\'"]\n\s+[\'"]x',
diff --git a/tests/test-check-code.t b/tests/test-check-code.t
--- a/tests/test-check-code.t
+++ b/tests/test-check-code.t
@@ -9,7 +9,16 @@ New errors are not allowed. Warnings are
 
   $ hg locate -X contrib/python-zstandard -X hgext/fsmonitor/pywatchman |
   > sed 's-\\-/-g' | xargs "$check_code" --warnings --per-file=0 || false
+  contrib/perf.py:859:
+   >             r.revision(r.node(x))
+   don't covert rev to node before passing to revision(nodeorrev)
   Skipping i18n/polib.py it has no-che?k-code (glob)
+  mercurial/bundlerepo.py:117:
+   >         return mdiff.textdiff(self.revision(self.node(rev1)),
+   don't covert rev to node before passing to revision(nodeorrev)
+  mercurial/bundlerepo.py:118:
+   >                               self.revision(self.node(rev2)))
+   don't covert rev to node before passing to revision(nodeorrev)
   mercurial/demandimport.py:312:
    >     if os.environ.get('HGDEMANDIMPORT') != 'disable':
    use encoding.environ instead (py3)
@@ -36,7 +45,22 @@ New errors are not allowed. Warnings are
   mercurial/policy.py:49:
    >     policy = os.environ.get('HGMODULEPOLICY', policy)
    use encoding.environ instead (py3)
+  mercurial/revlog.py:441:
+   >         t = self.revision(self.node(rev))
+   don't covert rev to node before passing to revision(nodeorrev)
+  mercurial/revlog.py:1599:
+   >                 basetext = self.revision(self.node(baserev), _df=fh, raw=raw)
+   don't covert rev to node before passing to revision(nodeorrev)
+  mercurial/revlog.py:1631:
+   >                     ptext = self.revision(self.node(rev), _df=fh)
+   don't covert rev to node before passing to revision(nodeorrev)
   Skipping mercurial/statprof.py it has no-che?k-code (glob)
+  mercurial/unionrepo.py:93:
+   >         return mdiff.textdiff(self.revision(self.node(rev1)),
+   don't covert rev to node before passing to revision(nodeorrev)
+  mercurial/unionrepo.py:94:
+   >                               self.revision(self.node(rev2)))
+   don't covert rev to node before passing to revision(nodeorrev)
   [1]
 
 @commands in debugcommands.py should be in alphabetical order.
diff --git a/tests/test-contrib-perf.t b/tests/test-contrib-perf.t
--- a/tests/test-contrib-perf.t
+++ b/tests/test-contrib-perf.t
@@ -165,3 +165,7 @@ Check perf.py for historical portability
   $ (hg files -r 1.2 glob:mercurial/*.c glob:mercurial/*.py;
   >  hg files -r tip glob:mercurial/*.c glob:mercurial/*.py) |
   > "$TESTDIR"/check-perf-code.py contrib/perf.py
+  contrib/perf.py:859:
+   >             r.revision(r.node(x))
+   don't covert rev to node before passing to revision(nodeorrev)
+  [1]