From 04d1591c7dcab4600baa9ecfc6f4123be428b941 Mon Sep 17 00:00:00 2001
From: kalmarek <kalmar@amu.edu.pl>
Date: Fri, 27 Oct 2017 16:16:43 +0200
Subject: [PATCH] actually cache and use savedhash + tests

---
 src/AutGroup.jl        | 11 +++++++----
 test/AutGroup-tests.jl | 10 ++++++++++
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/src/AutGroup.jl b/src/AutGroup.jl
index 50bb322..56e6758 100644
--- a/src/AutGroup.jl
+++ b/src/AutGroup.jl
@@ -201,8 +201,11 @@ end
 hash(s::AutSymbol, h::UInt) = hash(s.str, hash(s.pow, hash(:AutSymbol, h)))
 
 function hash(g::AutGroupElem, h::UInt)
-   gs = gens(parent(g).objectGroup)
-   return hash(g(gs), hash(typeof(g), hash(parent(g), h)))
+   if g.modified
+      g.savedhash = hash(g(gens(parent(g).objectGroup)), hash(typeof(g), hash(parent(g), h)))
+      g.modified = false
+   end
+   return g.savedhash
 end
 
 function change_pow(s::AutSymbol, n::Int)
@@ -316,7 +319,7 @@ function reduce!(W::AutGroupElem)
         end
     end
 
-    W.modified = false
-    W.savedhash = hash(W.symbols,hash(typeof(W)))
+    W.modified = true
+
     return W
 end
diff --git a/test/AutGroup-tests.jl b/test/AutGroup-tests.jl
index 0436d4d..e7adc3d 100644
--- a/test/AutGroup-tests.jl
+++ b/test/AutGroup-tests.jl
@@ -149,6 +149,16 @@
       b = Groups.flip_autsymbol(2)*A(inv(Groups.rmul_autsymbol(1,2)))
       @test a*b == b*a
       @test a^3 * b^3 == A()
+      g,h = Nemo.gens(A)[[1,8]]
+      domain = Nemo.gens(A.objectGroup)
+      @test (g*h)(domain) == (h*g)(domain)
+      @test (g*h).savedhash != (h*g).savedhash
+      a = g*h
+      b = h*g
+      @test hash(a) == hash(b)
+      @test a.savedhash == b.savedhash
+      @test length(unique([a,b])) == 1
+      @test length(unique([g*h, h*g])) == 1
    end
 
    @testset "specific Aut(F4) tests" begin