[test] eff. prop + class inheritance & overrides

Author: kavon

test/decl/class/effectful_properties.swift

@@ -0,0 +1,96 @@
+// RUN: %target-typecheck-verify-swift -enable-experimental-concurrency
+
+// REQUIRES: concurrency
+
+enum E : Error {
+  case NotAvailable
+}
+
+class GolfCourse {
+  var yards : Int {
+    get throws { throw E.NotAvailable }
+  }
+  var holes : Int {
+    get { 18 }
+  }
+
+  var par : Int {
+    get async throws { 71 }
+  }
+
+  subscript(_ i : Int) -> Int {
+    get throws { throw E.NotAvailable }
+  }
+}
+
+class Presidio : GolfCourse {
+  private var yardsFromBackTees = 6481
+  override var yards : Int { // removes effect & makes it mutable
+    get {
+      do {
+        return try super.yards
+      } catch {
+        return yardsFromBackTees
+      }
+    }
+    set { yardsFromBackTees = newValue }
+  }
+
+  override var holes : Int {  // expected-error {{cannot override non-'async' property with 'async' property}}
+    get async { 18 }
+  }
+
+  override var par : Int {
+    get async { 72 } // removes the 'throws' effect
+  }
+
+  override subscript(_ i : Int) -> Int { // removes effects
+    get { (try? super[i]) ?? 3 }
+  }
+}
+
+class PresidioBackNine : Presidio {
+  override var par : Int { // expected-error{{cannot override non-'throws' property with 'throws' property}}
+    get throws { 36 } // attempts to put the 'throws' effect back
+  }
+
+  override subscript(_ i : Int) -> Int { // expected-error{{cannot override non-'async' subscript with 'async' subscript}}
+    get async throws { 0 }
+  }
+}
+
+func timeToPlay(gc : Presidio) async {
+  _ = gc.yards
+  _ = (gc as GolfCourse).yards // expected-error{{property access can throw, but it is not marked with 'try' and the error is not handled}}
+  _ = try? (gc as GolfCourse).yards
+
+  // expected-error@+2 {{property access can throw, but it is not marked with 'try' and the error is not handled}}
+  // expected-error@+1 {{property access is 'async' but is not marked with 'await'}}
+  _ = (gc as GolfCourse).par
+  _ = try? await (gc as GolfCourse).par
+
+  _ = await gc.par
+
+  _ = gc[2]
+  _ = (gc as GolfCourse)[2] // expected-error{{subscript access can throw, but it is not marked with 'try' and the error is not handled}}
+  _ = try? (gc as GolfCourse)[2]
+}
+
+class AcceptableDynamic {
+  dynamic var par : Int {
+    get async throws { 60 }
+  }
+
+  dynamic subscript(_ i : Int) -> Int {
+    get throws { throw E.NotAvailable }
+  }
+}
+
+// mainly just some sanity checks
+class Misc {
+  // expected-error@+2 {{'lazy' cannot be used on a computed property}}
+  // expected-error@+1 {{lazy properties must have an initializer}}
+  lazy var someProp : Int {
+    get throws { 0 }
+  }
+}

test/decl/class/effectful_properties_objc.swift

@@ -0,0 +1,18 @@
+// RUN: %target-typecheck-verify-swift -enable-experimental-concurrency
+
+// REQUIRES: concurrency
+// REQUIRES: objc_interop
+
+enum E : Error {
+  case NotAvailable
+}
+
+class ProblematicObjC {
+  @objc var par : Int { // expected-error{{property with 'throws' or 'async' is not representable in Objective-C}}
+    get async throws { 60 }
+  }
+
+  @objc subscript(_ i : Int) -> Int { // expected-error{{subscript with 'throws' or 'async' is not representable in Objective-C}}
+    get throws { throw E.NotAvailable }
+  }
+}