pretty print Map in debug mode

Author: paulofaria

Sources/GraphQL/Map/Map.swift

@@ -697,6 +697,8 @@ extension Map : ExpressibleByDictionaryLiteral {
 
 extension Map : CustomStringConvertible {
     public var description: String {
+        var indentLevel = 0
+
         let escapeMapping: [Character: String] = [
             "\r": "\\r",
             "\n": "\\n",
@@ -739,33 +741,74 @@ extension Map : CustomStringConvertible {
 
         func serialize(array: [Map]) -> String {
             var string = "["
+
+            if _isDebugAssertConfiguration() {
+                indentLevel += 1
+            }
 
             for index in 0 ..< array.count {
+                if _isDebugAssertConfiguration() {
+                    string += "\n"
+                    string += indent()
+                }
+
                 string += serialize(map: array[index])
 
                 if index != array.count - 1 {
-                    string += ","
+                    if _isDebugAssertConfiguration() {
+                        string += ", "
+                    } else {
+                        string += ","
+                    }
                 }
             }
-            
-            return string + "]"
+
+            if _isDebugAssertConfiguration() {
+                indentLevel -= 1
+                return string + "\n" + indent() + "]"
+            } else {
+                return string + "]"
+            }
         }
 
         func serialize(dictionary: [String: Map]) -> String {
             var string = "{"
             var index = 0
+
+            if _isDebugAssertConfiguration() {
+                indentLevel += 1
+            }
 
             for (key, value) in dictionary.sorted(by: {$0.0 < $1.0}) {
-                string += escape(key) + ":" + serialize(map: value)
-                
+                if _isDebugAssertConfiguration() {
+                    string += "\n"
+                    string += indent()
+                    string += escape(key) + ": " + serialize(map: value)
+                } else {
+                    string += escape(key) + ":" + serialize(map: value)
+                }
+
                 if index != dictionary.count - 1 {
-                    string += ","
+                    if _isDebugAssertConfiguration() {
+                        string += ", "
+                    } else {
+                        string += ","
+                    }
                 }
 
                 index += 1
             }
-            
-            return string + "}"
+
+            if _isDebugAssertConfiguration() {
+                indentLevel -= 1
+                return string + "\n" + indent() + "}"
+            } else {
+                return string + "}"
+            }
+        }
+
+        func indent() -> String {
+            return String(repeating: "    ", count: indentLevel)
         }
 
         return serialize(map: self)

Tests/GraphQLTests/HelloWorldTests/HelloWorldTests.swift

@@ -16,21 +16,29 @@ class HelloWorldTests : XCTestCase {
 
     func testHello() throws {
         let query = "{ hello }"
-        let expected: Map = ["hello": "world"]
+        let expected: Map = [
+            "data": [
+                "hello": "world"
+            ]
+        ]
         let result = try graphql(schema: schema, request: query)
-        XCTAssertEqual(result["data"], expected)
+        XCTAssertEqual(result, expected)
     }
 
     func testBoyhowdy() throws {
         let query = "{ boyhowdy }"
 
-        let expectedErrors: Map = [[
-            "message": "Cannot query field \"boyhowdy\" on type \"RootQueryType\".",
-            "locations": [["line": 1, "column": 3]]
-        ]]
+        let expectedErrors: Map = [
+            "errors": [
+                [
+                    "message": "Cannot query field \"boyhowdy\" on type \"RootQueryType\".",
+                    "locations": [["line": 1, "column": 3]]
+                ]
+            ]
+        ]
 
         let result = try graphql(schema: schema, request: query)
-        XCTAssertEqual(result["errors"], expectedErrors)
+        XCTAssertEqual(result, expectedErrors)
     }
 }