Merge pull request #17 from alickbass/flatMap-array

Flat map array
alickbass · Feb 20, 2017 · 8265da1 · 8265da1
2 parents 867e010 + 1a63362
commit 8265da1
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Showing 2 changed files with 40 additions and 2 deletions.
diff --git a/SwiftyJSONModel/JSONObject.swift b/SwiftyJSONModel/JSONObject.swift
@@ -55,7 +55,7 @@ public extension JSONObject where PropertyType.RawValue == String {
         return try value(for: keyPath)
     }
 
-    public func value<T: JSONInitializable>(for keyPath: [PropertyType]) throws -> T {
+    private func value<T: JSONInitializable>(for keyPath: [PropertyType]) throws -> T {
         assert(keyPath.isEmpty == false, "KeyPath cannot be empty")
 
         let key = keyPath[0]
@@ -75,7 +75,7 @@ public extension JSONObject where PropertyType.RawValue == String {
         return try value(for: keyPath)
     }
 
-    public func value<T: JSONInitializable>(for keyPath: [PropertyType]) throws -> [T] {
+    private func value<T: JSONInitializable>(for keyPath: [PropertyType]) throws -> [T] {
         assert(keyPath.isEmpty == false, "KeyPath cannot be empty")
 
         let key = keyPath[0]
@@ -97,6 +97,26 @@ public extension JSONObject where PropertyType.RawValue == String {
         }
     }
 
+    public func flatMap<T: JSONInitializable>(for keyPath: PropertyType...) throws -> [T] {
+        return try flatMap(for: keyPath)
+    }
+
+    private func flatMap<T: JSONInitializable>(for keyPath: [PropertyType]) throws -> [T] {
+        assert(keyPath.isEmpty == false, "KeyPath cannot be empty")
+
+        let key = keyPath[0]
+        do {
+            if keyPath.count == 1 {
+                return try self[key].arrayValue().lazy.flatMap({ try? T(json: $0) })
+            } else {
+                let subPath: [PropertyType] = .init(keyPath[1..<keyPath.count])
+                return try JSONObject<PropertyType>(json: self[key]).flatMap(for: subPath)
+            }
+        } catch let error as JSONModelError {
+            throw JSONModelError.invalidValueFor(key: key.rawValue, error)
+        }
+    }
+
     // MARK: - Optional methods
     public func value<T: JSONInitializable>(for keyPath: PropertyType...) -> T? {
         return try? value(for: keyPath)

diff --git a/SwiftyJSONModelTests/JSONObjectTests.swift b/SwiftyJSONModelTests/JSONObjectTests.swift
@@ -124,4 +124,22 @@ class JSONObjectTests: XCTestCase {
         XCTAssertEqual((object.value(for: .first, .second, .array) as [Int]?)!, [1, 2, 3])
         XCTAssertNil(object.value(for: .first, .second, .array) as [String]?)
     }
+
+    func testJSONObjectFlatMap() {
+        enum PropertyKey: String {
+            case first, second, third, array
+        }
+
+        let nestedJSON: JSON = ["first": ["second": ["third": 3, "array": [1, "test", 3]]]]
+        let object = try! JSONObject<PropertyKey>(json: nestedJSON)
+
+        XCTAssertEqual(try! object.flatMap(for: .first, .second, .array), [1, 3])
+        XCTAssertEqual(try! object.flatMap(for: .first, .second, .array), ["test"])
+        XCTAssertThrowsError(try object.flatMap(for: .first, .second, .third) as [Int]) { error in
+            let first = PropertyKey.first.rawValue
+            let second = PropertyKey.second.rawValue
+            let third = PropertyKey.third.rawValue
+            XCTAssertEqual(error as? JSONModelError, .invalidValueFor(key: first,  .invalidValueFor(key: second, .invalidValueFor(key: third, .invalidElement))))
+        }
+    }
 }