Add tests for flat dictionary, fix dictionaryLiteral (#182)

Sources/Hummingbird/Utils/FlatDictionary.swift

@@ -22,7 +22,7 @@
 /// functions will always return the first key found, but if you
 /// iterate through the key,value pairs you can access all values
 /// for a key
-public struct FlatDictionary<Key: Hashable, Value>: Collection {
+public struct FlatDictionary<Key: Hashable, Value>: Collection, ExpressibleByDictionaryLiteral {
     public typealias Element = (key: Key, value: Value)
     public typealias Index = Array<Element>.Index
 

Tests/HummingbirdTests/UtilsTests.swift

@@ -0,0 +1,39 @@
+//===----------------------------------------------------------------------===//
+//
+// This source file is part of the Hummingbird server framework project
+//
+// Copyright (c) 2023 the Hummingbird authors
+// Licensed under Apache License v2.0
+//
+// See LICENSE.txt for license information
+// See hummingbird/CONTRIBUTORS.txt for the list of Hummingbird authors
+//
+// SPDX-License-Identifier: Apache-2.0
+//
+//===----------------------------------------------------------------------===//
+
+import Hummingbird
+import XCTest
+
+class FlatDictionaryTests: XCTestCase {
+    func testLiteralInit() {
+        let a: FlatDictionary<String, String> = ["test": "value", "key2": "value2"]
+        XCTAssertEqual(a["test"], "value")
+        XCTAssertEqual(a["key2"], "value2")
+    }
+
+    func testKeyGetSet() {
+        var a: FlatDictionary<String, String> = [:]
+        a["key"] = "value"
+        XCTAssertEqual(a["key"], "value")
+        a["key"] = nil
+        XCTAssertEqual(a["key2"], nil)
+    }
+
+    func testKeyGetFirst() {
+        var a: FlatDictionary<String, String> = [:]
+        a.append(key: "key", value: "value1")
+        a.append(key: "key", value: "value2")
+        XCTAssertEqual(a["key"], "value1")
+    }
+}