Add library evolution tests for re-ordering protocol requirements

Author: slavapestov

validation-test/Evolution/Inputs/protocol_reorder_requirements.swift

@@ -0,0 +1,69 @@
+public protocol Bed {
+  func squiggle()
+}
+
+public protocol Outfit {
+  var size: Int { get }
+}
+
+public protocol Eater {
+#if BEFORE
+  func eat()
+  func poop()
+#else
+  func poop()
+  func eat()
+#endif
+}
+
+public protocol Wiggler {
+#if BEFORE
+  func wiggle()
+  func cry()
+#else
+  func cry()
+  func wiggle()
+#endif
+}
+
+#if BEFORE
+
+public protocol Baby : Eater, Wiggler {
+  associatedtype Bassinet : Bed
+  associatedtype Onesie : Outfit
+
+  var outfitSize: Int { get }
+
+  func sleep(in: Bassinet)
+  func wear(outfit: Onesie)
+}
+
+#else
+
+public protocol Baby : Wiggler, Eater {
+  associatedtype Onesie : Outfit
+  associatedtype Bassinet : Bed
+
+  var outfitSize: Int { get }
+
+  func wear(outfit: Onesie)
+  func sleep(in: Bassinet)
+}
+
+#endif
+
+public func goodDay<B : Baby>(for baby: B,
+                              sleepingIn bed: B.Bassinet,
+                              wearing outfit: B.Onesie) {
+  if baby.outfitSize != outfit.size {
+    fatalError("I grew too much!")
+  }
+
+  baby.wear(outfit: outfit)
+  baby.sleep(in: bed)
+  baby.poop()
+  baby.sleep(in: bed)
+  baby.eat()
+  baby.sleep(in: bed)
+  baby.wiggle()
+}

validation-test/Evolution/test_protocol_reorder_requirements.swift

@@ -0,0 +1,94 @@
+// RUN: %target-resilience-test --no-backward-deployment
+// REQUIRES: executable_test
+
+import StdlibUnittest
+import protocol_reorder_requirements
+
+
+var ProtocolReorderRequirementsTest = TestSuite("ProtocolReorderRequirements")
+
+var log = [String]()
+
+struct MyBassinet : Bed {
+  func squiggle() {
+    log.append("nap time")
+  }
+}
+
+struct MyOnesie : Outfit {
+  let size = 3
+}
+
+struct SillyBaby : Baby {
+  func eat() {
+    log.append("hangry!")
+  }
+
+  func sleep(in bassinet: MyBassinet) {
+    bassinet.squiggle()
+  }
+
+  func wear(outfit: MyOnesie) {
+    log.append("wearing outfit size \(outfit.size)")
+  }
+
+  func poop() {
+    log.append("change the diaper")
+  }
+
+  func cry() {
+    log.append("waaaaah!")
+  }
+
+  func wiggle() {
+    log.append("time to wiggle!")
+  }
+
+  let outfitSize = 3
+}
+
+func typicalDay<B : Baby>(for baby: B,
+                          sleepingIn bed: B.Bassinet,
+                          wearing outfit: B.Onesie) {
+  baby.wear(outfit: outfit)
+  baby.sleep(in: bed)
+  baby.cry()
+  baby.poop()
+  baby.cry()
+  baby.sleep(in: bed)
+  baby.eat()
+  baby.cry()
+}
+
+ProtocolReorderRequirementsTest.test("ReorderProtocolRequirements") {
+  let baby = SillyBaby()
+  let bed = MyBassinet()
+  let outfit = MyOnesie()
+
+  typicalDay(for: baby, sleepingIn: bed, wearing: outfit)
+  expectEqual(log, [
+      "wearing outfit size 3",
+      "nap time",
+      "waaaaah!",
+      "change the diaper",
+      "waaaaah!",
+      "nap time",
+      "hangry!",
+      "waaaaah!"
+    ])
+  log = []
+
+  goodDay(for: baby, sleepingIn: bed, wearing: outfit)
+  expectEqual(log, [
+      "wearing outfit size 3",
+      "nap time",
+      "change the diaper",
+      "nap time",
+      "hangry!",
+      "nap time",
+      "time to wiggle!"
+    ])
+}
+
+runAllTests()
+