--- a/mercurial/filesetlang.py	Sun Jul 22 11:47:29 2018 +0900
+++ b/mercurial/filesetlang.py	Sat Jul 21 16:41:45 2018 +0900
@@ -184,7 +184,14 @@
     if op == 'not':
         w, t = _optimize(x[1])
         return w, (op, t)
-    if op in {'and', 'minus'}:
+    if op == 'and':
+        wa, ta = _optimize(x[1])
+        wb, tb = _optimize(x[2])
+        if wa <= wb:
+            return wa, (op, ta, tb)
+        else:
+            return wb, (op, tb, ta)
+    if op == 'minus':
         wa, ta = _optimize(x[1])
         wb, tb = _optimize(x[2])
         return max(wa, wb), (op, ta, tb)

--- a/tests/test-fileset.t	Sun Jul 22 11:47:29 2018 +0900
+++ b/tests/test-fileset.t	Sat Jul 21 16:41:45 2018 +0900
@@ -186,18 +186,18 @@
     (symbol 'a2')
     (and
       (func
-        (symbol 'grep')
-        (string 'b'))
+        (symbol 'clean')
+        None)
       (func
-        (symbol 'clean')
-        None)))
+        (symbol 'grep')
+        (string 'b'))))
   * matcher:
   <unionmatcher matchers=[
     <patternmatcher patterns='(?:a1$)'>,
     <patternmatcher patterns='(?:a2$)'>,
     <intersectionmatcher
-      m1=<predicatenmatcher pred=grep('b')>,
-      m2=<predicatenmatcher pred=clean>>]>
+      m1=<predicatenmatcher pred=clean>,
+      m2=<predicatenmatcher pred=grep('b')>>]>
   a1
   a2
   b1
@@ -283,6 +283,19 @@
   $ fileset 'binary()'
   bin
 
+  $ fileset -p optimized -s 'binary() and b*'
+  * optimized:
+  (and
+    (symbol 'b*')
+    (func
+      (symbol 'binary')
+      None))
+  * matcher:
+  <intersectionmatcher
+    m1=<patternmatcher patterns='(?:b[^/]*$)'>,
+    m2=<predicatenmatcher pred=binary>>
+  bin
+
   $ fileset 'grep("b{1}")'
   .hgignore
   b1