add Hash and Eq to Dict and Set

crates/compiler/builtins/roc/Dict.roc

@@ -98,6 +98,30 @@ Dict k v := {
     data : List (T k v),
     size : Nat,
 } | k has Hash & Eq
+     has [
+         Eq {
+             isEq,
+         },
+         Hash {
+             hash: hashDict,
+         },
+     ]
+
+isEq : Dict k v, Dict k v -> Bool | k has Hash & Eq, v has Eq
+isEq = \xs, ys ->
+    if len xs != len ys then
+        Bool.false
+    else
+        walkUntil xs Bool.true \_, k, xVal ->
+            when get ys k is
+                Ok yVal if yVal == xVal ->
+                    Continue Bool.true
+
+                _ ->
+                    Break Bool.false
+
+hashDict : hasher, Dict k v -> hasher | k has Hash & Eq, v has Hash, hasher has Hasher
+hashDict = \hasher, dict -> Hash.hashUnordered hasher (toList dict) List.walk
 
 ## Return an empty dictionary.
 ## ```
@@ -747,6 +771,71 @@ expect
 
     val == Ok "bar"
 
+expect
+    dict1 =
+        empty {}
+        |> insert 1 "bar"
+        |> insert 2 "baz"
+
+    dict2 =
+        empty {}
+        |> insert 2 "baz"
+        |> insert 1 "bar"
+
+    dict1 == dict2
+
+expect
+    dict1 =
+        empty {}
+        |> insert 1 "bar"
+        |> insert 2 "baz"
+
+    dict2 =
+        empty {}
+        |> insert 1 "bar"
+        |> insert 2 "baz!"
+
+    dict1 != dict2
+
+expect
+    inner1 =
+        empty {}
+        |> insert 1 "bar"
+        |> insert 2 "baz"
+
+    inner2 =
+        empty {}
+        |> insert 2 "baz"
+        |> insert 1 "bar"
+
+    outer =
+        empty {}
+        |> insert inner1 "wrong"
+        |> insert inner2 "right"
+
+    get outer inner1 == Ok "right"
+
+expect
+    inner1 =
+        empty {}
+        |> insert 1 "bar"
+        |> insert 2 "baz"
+
+    inner2 =
+        empty {}
+        |> insert 2 "baz"
+        |> insert 1 "bar"
+
+    outer1 =
+        empty {}
+        |> insert inner1 "val"
+
+    outer2 =
+        empty {}
+        |> insert inner2 "val"
+
+    outer1 == outer2
+
 expect
     val =
         empty {}

crates/compiler/builtins/roc/Set.roc

@@ -20,7 +20,7 @@ interface Set
         Bool.{ Bool, Eq },
         Dict.{ Dict },
         Num.{ Nat },
-        Hash.{ Hash },
+        Hash.{ Hash, Hasher },
     ]
 
 # We should have this line above the next has.
@@ -28,11 +28,14 @@ interface Set
 # | k has Hash & Eq
 ## Provides a [set](https://en.wikipedia.org/wiki/Set_(abstract_data_type))
 ## type which stores a collection of unique values, without any ordering
-Set k := Dict.Dict k {}
+Set k := Dict.Dict k {} | k has Hash & Eq
      has [
          Eq {
              isEq,
          },
+         Hash {
+             hash: hashSet,
+         },
      ]
 
 isEq : Set k, Set k -> Bool | k has Hash & Eq
@@ -46,6 +49,9 @@ isEq = \xs, ys ->
             else
                 Break Bool.false
 
+hashSet : hasher, Set k -> hasher | k has Hash & Eq, hasher has Hasher
+hashSet = \hasher, @Set inner -> Hash.hash hasher inner
+
 ## Creates a new empty `Set`.
 ## ```
 ## emptySet = Set.empty {}
@@ -353,3 +359,27 @@ expect
         |> insert 9
 
     x == fromList (toList x)
+
+# TODO: This test that puts a Set in a Set fails to unify.
+# expect
+#     orderOne : Set Nat
+#     orderOne =
+#         single 1
+#         |> insert 2
+
+#     orderTwo : Set Nat
+#     orderTwo =
+#         single 2
+#         |> insert 1
+
+#     wrapperOne : Set (Set Nat)
+#     wrapperOne =
+#         single orderOne
+#         |> insert orderTwo
+
+#     wrapperTwo : Set (Set Nat)
+#     wrapperTwo =
+#         single orderTwo
+#         |> insert orderOne
+
+#     wrapperOne == wrapperTwo