Added conditional conformance fo Equatable and Hashable for DictionaryLiteral. Added tests too.

Author: mortenbekditlevsen

stdlib/public/core/Mirror.swift

@@ -905,6 +905,43 @@ extension DictionaryLiteral : RandomAccessCollection {
   }
 }
 
+extension DictionaryLiteral : Equatable where Key: Equatable, Value : Equatable {
+  @_inlineable // FIXME(sil-serialize-all)
+  public static func ==(lhs: DictionaryLiteral<Key, Value>, rhs: DictionaryLiteral<Key, Value>) -> Bool {
+    let lhsCount = lhs.count
+    if lhsCount != rhs.count {
+        return false
+    }
+    // We know that lhs.count == rhs.count, compare element wise.
+    for idx in 0..<lhsCount {
+        if lhs[idx].key != rhs[idx].key ||
+            lhs[idx].value != rhs[idx].value {
+            return false
+        }
+    }
+    return true
+  }
+}
+
+extension DictionaryLiteral : Hashable where Key: Hashable, Value : Hashable {
+  /// The hash value for the dictionary.
+  ///
+  /// Two dictionaries that are equal will always have equal hash values.
+  ///
+  /// Hash values are not guaranteed to be equal across different executions of
+  /// your program. Do not save hash values to use during a future execution.
+  @_inlineable // FIXME(sil-serialize-all)
+  public var hashValue: Int {
+    // FIXME(ABI)#177: <rdar://problem/18915294> Issue applies to DictionaryLiteral too
+    var result: Int = 0
+    for element in self {
+      let elementHashValue = _combineHashValues(element.key.hashValue, element.value.hashValue)
+      result = _combineHashValues(result, elementHashValue)
+    }
+    return result
+  }
+}
+
 extension String {
   /// Creates a string representing the given value.
   ///

test/stdlib/DictionaryLiteral.swift

@@ -54,3 +54,12 @@ expectType(DictionaryLiteral<String, NSObject>.self, &hetero1)
 
 var hetero2: DictionaryLiteral = ["a": 1 as NSNumber, "b": "Foo" as NSString]
 expectType(DictionaryLiteral<String, NSObject>.self, &hetero2)
+
+let instances: [DictionaryLiteral<Int, String>] = [
+  [1: "a", 1: "a", 2: "b"],
+  [1: "a", 2: "b", 1: "a"],
+  [2: "b", 1: "a", 1: "a"],
+  [1: "a", 1: "a", 1: "a"]
+]
+checkEquatable(instances, oracle: { $0 == $1 })
+checkHashable(instances, equalityOracle: { $0 == $1 })