fix #6870, hashing collections

JuliaLang · May 19, 2014 · 00081d7 · 00081d7 · StefanKarpinski · May 19, 2014
1 parent 18d1266
commit 00081d7
Show file tree

Hide file tree

Showing 2 changed files with 19 additions and 3 deletions.
diff --git a/base/hashing2.jl b/base/hashing2.jl
@@ -166,14 +166,19 @@ hash(s::String, h::Uint) = hash(bytestring(s), h)
 
 ## hashing collections ##
 
-function hash(v::Union(Tuple,AbstractArray,Associative), h::Uint)
-    h += object_id(eltype(v))
-    for x = v
+function hash(v::Union(AbstractArray,Associative), h::Uint)
+    h += uint(isa(v,Associative) ? 0x6d35bb51952d5539 : 0x7f53e68ceb575e76)
+    for x in v
         h = hash(x, h)
     end
     return h
 end
 
+hash(::(), h::Uint) = h + uint(0x77cfa1eef01bca90)
+hash(x::(Any,), h::Uint)    = hash(x[1], hash((), h))
+hash(x::(Any,Any), h::Uint) = hash(x[1], hash(x[2], hash((), h)))
+hash(x::Tuple, h::Uint)     = hash(x[1], hash(x[2], hash(tupletail(x), h)))
+
 hash(s::Set, h::Uint) = hash(sort(s.dict.keys[s.dict.slots .!= 0]), h)
 
 hash(r::Range{Bool}, h::Uint) = invoke(hash, (Range, Uint), r, h)

diff --git a/test/hashing.jl b/test/hashing.jl
@@ -29,6 +29,17 @@ for T=types, S=types, x=vals
     # end
 end
 
+# hashing collections (e.g. issue #6870)
+vals = {[1,2,3,4], [1 2;3 4], {1,2,3,4}, [1,3,2,4],
+        Set([1,2,3,4]),
+        [42 => 101, 77 => 93], {42 => 101, 77 => 93},
+        (1,2,3,4), (1.0,2.0,3.0,4.0), (1,3,2,4),
+        ("a","b"), (SubString("a",1,1), SubString("b",1,1))}
+
+for a in vals, b in vals
+    @test !isequal(a,b) || hash(a)==hash(b)
+end
+
 @test hash(RopeString("1","2")) == hash("12")
 @test hash(SubString("--hello--",3,7)) == hash("hello")
 @test hash(:(X.x)) == hash(:(X.x))