diff --git a/mercurial/scmutil.py b/mercurial/scmutil.py
--- a/mercurial/scmutil.py
+++ b/mercurial/scmutil.py
@@ -1211,9 +1211,9 @@
     try:
         similarity = float(opts.get(b'similarity') or 0)
     except ValueError:
-        raise error.Abort(_(b'similarity must be a number'))
+        raise error.InputError(_(b'similarity must be a number'))
     if similarity < 0 or similarity > 100:
-        raise error.Abort(_(b'similarity must be between 0 and 100'))
+        raise error.InputError(_(b'similarity must be between 0 and 100'))
     similarity /= 100.0
 
     ret = 0
diff --git a/tests/test-addremove-similar.t b/tests/test-addremove-similar.t
--- a/tests/test-addremove-similar.t
+++ b/tests/test-addremove-similar.t
@@ -131,13 +131,13 @@
 
   $ hg addremove -s foo
   abort: similarity must be a number
-  [255]
+  [10]
   $ hg addremove -s -1
   abort: similarity must be between 0 and 100
-  [255]
+  [10]
   $ hg addremove -s 1e6
   abort: similarity must be between 0 and 100
-  [255]
+  [10]
 
   $ cd ..