diff --git a/Tests/XMLCoderTests/Minimal/BoolTests.swift b/Tests/XMLCoderTests/Minimal/BoolTests.swift
index 1d9803aa..ce41aaca 100644
--- a/Tests/XMLCoderTests/Minimal/BoolTests.swift
+++ b/Tests/XMLCoderTests/Minimal/BoolTests.swift
@@ -76,6 +76,7 @@ class BoolTests: XCTestCase {
     }
 
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
     ]
diff --git a/Tests/XMLCoderTests/Minimal/DataTests.swift b/Tests/XMLCoderTests/Minimal/DataTests.swift
index 695d3e3a..54934cf0 100644
--- a/Tests/XMLCoderTests/Minimal/DataTests.swift
+++ b/Tests/XMLCoderTests/Minimal/DataTests.swift
@@ -76,8 +76,129 @@ class DataTests: XCTestCase {
         }
     }
 
+    func testStrategy() throws {
+        let decoder = XMLDecoder()
+        let encoder = XMLEncoder()
+
+        encoder.outputFormatting = [.prettyPrinted]
+
+        for (value, xmlString) in values {
+            let xmlString =
+                """
+                <container>
+                    <value>\(xmlString)</value>
+                </container>
+                """
+            let xmlData = xmlString.data(using: .utf8)!
+
+            let decoded = try decoder.decode(Container.self, from: xmlData)
+            XCTAssertEqual(decoded.value, value)
+
+            let encoded = try encoder.encode(decoded, withRootKey: "container")
+            XCTAssertEqual(String(data: encoded, encoding: .utf8)!, xmlString)
+        }
+    }
+
+    func testKeyFormated() throws {
+        let decoder = XMLDecoder()
+        let encoder = XMLEncoder()
+
+        decoder.dataDecodingStrategy = .keyFormatted { $0.stringValue.data(using: .utf8) }
+
+        encoder.outputFormatting = [.prettyPrinted]
+
+        for (_, xmlString) in values {
+            let xmlString =
+                """
+                <container>
+                    <value>\(xmlString)</value>
+                </container>
+                """
+            let xmlData = xmlString.data(using: .utf8)!
+
+            let decoded = try decoder.decode(Container.self, from: xmlData)
+
+            XCTAssertEqual(decoded.value, Data("value".utf8))
+        }
+    }
+
+    func testKeyFormatedError() throws {
+        let decoder = XMLDecoder()
+        let encoder = XMLEncoder()
+
+        decoder.dataDecodingStrategy = .keyFormatted { codingKey in
+            return Data(base64Encoded: codingKey.stringValue)
+        }
+
+        encoder.outputFormatting = [.prettyPrinted]
+
+        for (_, xmlString) in values {
+            let xmlString =
+                """
+                <container>
+                    <value>\(xmlString)</value>
+                </container>
+                """
+            let xmlData = xmlString.data(using: .utf8)!
+
+            XCTAssertThrowsError(try decoder.decode(Container.self, from: xmlData))
+        }
+    }
+
+    func testKeyFormatedCouldNotDecodeError() throws {
+        let decoder = XMLDecoder()
+        let encoder = XMLEncoder()
+
+        decoder.dataDecodingStrategy = .keyFormatted { codingKey in
+            return Data(base64Encoded: codingKey.stringValue)
+        }
+
+        encoder.outputFormatting = [.prettyPrinted]
+
+        for (_, xmlString) in values {
+            let xmlString =
+                """
+                <container>
+                <value>\(xmlString)0</value>
+                <value>\(xmlString)0</value>
+                </container>
+                """
+            let xmlData = xmlString.data(using: .utf8)!
+
+            XCTAssertThrowsError(try decoder.decode(Container.self, from: xmlData))
+        }
+    }
+
+    func testKeyFormatedNoPathError() throws {
+        let decoder = XMLDecoder()
+        let encoder = XMLEncoder()
+
+        decoder.dataDecodingStrategy = .keyFormatted { codingKey in
+            return Data(base64Encoded: codingKey.stringValue)
+        }
+
+        encoder.outputFormatting = [.prettyPrinted]
+
+        for (_, _) in values {
+            let xmlString =
+                """
+                <container>
+                    <value>12</value>
+                </container>
+                """
+            let xmlData = xmlString.data(using: .utf8)!
+
+            XCTAssertThrowsError(try decoder.decode(Container.self, from: xmlData))
+        }
+    }
+
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
+        ("testKeyFormated", testKeyFormated),
+        ("testKeyFormatedError", testKeyFormatedError),
+        ("testKeyFormatedCouldNotDecodeError", testKeyFormatedCouldNotDecodeError),
+        ("testKeyFormatedNoPathError", testKeyFormatedNoPathError),
     ]
 }
diff --git a/Tests/XMLCoderTests/Minimal/DateTests.swift b/Tests/XMLCoderTests/Minimal/DateTests.swift
index ec73ab7e..6df21095 100644
--- a/Tests/XMLCoderTests/Minimal/DateTests.swift
+++ b/Tests/XMLCoderTests/Minimal/DateTests.swift
@@ -78,8 +78,88 @@ class DateTests: XCTestCase {
         }
     }
 
+    func testKeyFormatedError() throws {
+        let decoder = XMLDecoder()
+        let encoder = XMLEncoder()
+
+        decoder.dateDecodingStrategy = .keyFormatted { _ in
+            let formatter = DateFormatter()
+            formatter.dateFormat = "value"
+            return formatter
+        }
+
+        encoder.outputFormatting = [.prettyPrinted]
+
+        for (_, xmlString) in values {
+            let xmlString =
+                """
+                <container>
+                    <value>\(xmlString)</value>
+                </container>
+                """
+            let xmlData = xmlString.data(using: .utf8)!
+
+            XCTAssertThrowsError(try decoder.decode(Container.self, from: xmlData))
+        }
+    }
+
+    func testKeyFormatedCouldNotDecodeError() throws {
+        let decoder = XMLDecoder()
+        let encoder = XMLEncoder()
+
+        decoder.dateDecodingStrategy = .keyFormatted { _ in
+            let formatter = DateFormatter()
+            formatter.dateFormat = "value"
+            return formatter
+        }
+
+        encoder.outputFormatting = [.prettyPrinted]
+
+        for (_, xmlString) in values {
+            let xmlString =
+                """
+                <container>
+                <value>\(xmlString)</value>
+                <value>\(xmlString)</value>
+                </container>
+                """
+            let xmlData = xmlString.data(using: .utf8)!
+
+            XCTAssertThrowsError(try decoder.decode(Container.self, from: xmlData))
+        }
+    }
+
+    func testKeyFormatedNoPathError() throws {
+        let decoder = XMLDecoder()
+        let encoder = XMLEncoder()
+
+        decoder.dateDecodingStrategy = .keyFormatted { _ in
+            let formatter = DateFormatter()
+            formatter.dateFormat = "value"
+            return formatter
+        }
+
+        encoder.outputFormatting = [.prettyPrinted]
+
+        for (_, _) in values {
+            let xmlString =
+                """
+                <container>
+                    <value>12</value>
+                </container>
+                """
+            let xmlData = xmlString.data(using: .utf8)!
+
+            XCTAssertThrowsError(try decoder.decode(Container.self, from: xmlData))
+        }
+    }
+
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
+        ("testKeyFormatedError", testKeyFormatedError),
+        ("testKeyFormatedCouldNotDecodeError", testKeyFormatedCouldNotDecodeError),
+        ("testKeyFormatedNoPathError", testKeyFormatedNoPathError),
     ]
 }
diff --git a/Tests/XMLCoderTests/Minimal/DecimalTests.swift b/Tests/XMLCoderTests/Minimal/DecimalTests.swift
index 6cdcc5a2..79e951a1 100644
--- a/Tests/XMLCoderTests/Minimal/DecimalTests.swift
+++ b/Tests/XMLCoderTests/Minimal/DecimalTests.swift
@@ -77,6 +77,7 @@ class DecimalTests: XCTestCase {
     }
 
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
     ]
diff --git a/Tests/XMLCoderTests/Minimal/FloatTests.swift b/Tests/XMLCoderTests/Minimal/FloatTests.swift
index 5455e268..6e00ac5c 100644
--- a/Tests/XMLCoderTests/Minimal/FloatTests.swift
+++ b/Tests/XMLCoderTests/Minimal/FloatTests.swift
@@ -77,6 +77,7 @@ class FloatTests: XCTestCase {
     }
 
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
     ]
diff --git a/Tests/XMLCoderTests/Minimal/IntTests.swift b/Tests/XMLCoderTests/Minimal/IntTests.swift
index 7710b103..41a84fc6 100644
--- a/Tests/XMLCoderTests/Minimal/IntTests.swift
+++ b/Tests/XMLCoderTests/Minimal/IntTests.swift
@@ -76,6 +76,7 @@ class IntTests: XCTestCase {
     }
 
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
     ]
diff --git a/Tests/XMLCoderTests/Minimal/StringTests.swift b/Tests/XMLCoderTests/Minimal/StringTests.swift
index 9c9766f7..caedfe10 100644
--- a/Tests/XMLCoderTests/Minimal/StringTests.swift
+++ b/Tests/XMLCoderTests/Minimal/StringTests.swift
@@ -81,6 +81,7 @@ class StringTests: XCTestCase {
     }
 
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
     ]
diff --git a/Tests/XMLCoderTests/Minimal/UIntTests.swift b/Tests/XMLCoderTests/Minimal/UIntTests.swift
index 3476cc0d..e7e3a77e 100644
--- a/Tests/XMLCoderTests/Minimal/UIntTests.swift
+++ b/Tests/XMLCoderTests/Minimal/UIntTests.swift
@@ -76,6 +76,7 @@ class UIntTests: XCTestCase {
     }
 
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
     ]
diff --git a/Tests/XMLCoderTests/Minimal/URLTests.swift b/Tests/XMLCoderTests/Minimal/URLTests.swift
index f62fb3b1..3c4b57b2 100644
--- a/Tests/XMLCoderTests/Minimal/URLTests.swift
+++ b/Tests/XMLCoderTests/Minimal/URLTests.swift
@@ -76,6 +76,7 @@ class URLTests: XCTestCase {
     }
 
     static var allTests = [
+        ("testMissing", testMissing),
         ("testAttribute", testAttribute),
         ("testElement", testElement),
     ]