--- a/mercurial/cmdutil.py	Sat Jun 02 13:25:45 2018 -0400
+++ b/mercurial/cmdutil.py	Sat Jun 02 13:44:44 2018 -0400
@@ -3208,8 +3208,16 @@
     if found. It's probably good to check this right before
     bailifchanged().
     '''
+    # Check for non-clearable states first, so things like rebase will take
+    # precedence over update.
     for f, clearable, allowcommit, msg, hint in unfinishedstates:
-        if commit and allowcommit:
+        if clearable or (commit and allowcommit):
+            continue
+        if repo.vfs.exists(f):
+            raise error.Abort(msg, hint=hint)
+
+    for f, clearable, allowcommit, msg, hint in unfinishedstates:
+        if not clearable or (commit and allowcommit):
             continue
         if repo.vfs.exists(f):
             raise error.Abort(msg, hint=hint)

--- a/tests/test-rebase-abort.t	Sat Jun 02 13:25:45 2018 -0400
+++ b/tests/test-rebase-abort.t	Sat Jun 02 13:44:44 2018 -0400
@@ -387,10 +387,9 @@
   .hg/undo.dirstate
   .hg/updatestate
 
-XXX: This should complain about needing to abort/continue rebase
   $ hg rebase -s 3 -d tip
-  abort: last update was interrupted
-  (use 'hg update' to get a consistent checkout)
+  abort: rebase in progress
+  (use 'hg rebase --continue' or 'hg rebase --abort')
   [255]
   $ hg up .
   abort: rebase in progress
@@ -401,10 +400,9 @@
   (use 'hg rebase --continue' or 'hg rebase --abort')
   [255]
 
-XXX: This should complain about needing to abort/continue rebase
   $ hg graft 3
-  abort: last update was interrupted
-  (use 'hg update' to get a consistent checkout)
+  abort: rebase in progress
+  (use 'hg rebase --continue' or 'hg rebase --abort')
   [255]
 
   $ hg rebase --abort