Add tests

Author: calda

test/stmt/if_while_var.swift

@@ -1,6 +1,6 @@
 // RUN: %target-typecheck-verify-swift
 
-struct NonOptionalStruct {}
+struct NonOptionalStruct { let property: Any }
 enum NonOptionalEnum { case foo }
 
 func foo() -> Int? { return .none }
@@ -21,11 +21,30 @@ if var x = foo() {
   modify(&x)
 }
 
+if let x { // expected-error{{cannot find 'x' in scope}}
+  use(x)
+}
+
+if var x { // expected-error{{cannot find 'x' in scope}}
+  use(x)
+}
+
 use(x) // expected-error{{cannot find 'x' in scope}}
 
+let nonOptional = nonOptionalStruct()
+
 if let x = nonOptionalStruct() { _ = x} // expected-error{{initializer for conditional binding must have Optional type, not 'NonOptionalStruct'}}
 if let x = nonOptionalEnum() { _ = x} // expected-error{{initializer for conditional binding must have Optional type, not 'NonOptionalEnum'}}
 
+if let nonOptional { _ = nonOptional } // expected-error{{initializer for conditional binding must have Optional type, not 'NonOptionalStruct'}}
+if var nonOptional { nonOptional = nonOptionalStruct(); _ = nonOptional } // expected-error{{initializer for conditional binding must have Optional type, not 'NonOptionalStruct'}}
+
+guard let nonOptional else { _ = nonOptional; fatalError() } // expected-error{{initializer for conditional binding must have Optional type, not 'NonOptionalStruct'}}
+guard var nonOptional else { _ = nonOptional; fatalError() } // expected-error{{initializer for conditional binding must have Optional type, not 'NonOptionalStruct'}}
+
+if let nonOptional.property { } // expected-error{{variable binding in a condition requires an initializer}} expected-error{{pattern matching in a condition requires the 'case' keyword}}
+if var nonOptional.property { } // expected-error{{variable binding in a condition requires an initializer}} expected-error{{pattern matching in a condition requires the 'case' keyword}}
+
 guard let _ = nonOptionalStruct() else { fatalError() } // expected-error{{initializer for conditional binding must have Optional type, not 'NonOptionalStruct'}}
 guard let _ = nonOptionalEnum() else { fatalError() } // expected-error{{initializer for conditional binding must have Optional type, not 'NonOptionalEnum'}}
 
@@ -59,6 +78,16 @@ if let x = foo() {
 
 var opt: Int? = .none
 
+if let opt {
+  use(opt)
+  opt = 10 // expected-error{{cannot assign to value: 'opt' is a 'let' constant}}
+}
+
+if var opt {
+  use(opt)
+  opt = 10
+}
+
 if let x = opt {} // expected-warning {{value 'x' was defined but never used; consider replacing with boolean test}} {{4-12=}} {{15-15= != nil}}
 if var x = opt {} // expected-warning {{value 'x' was defined but never used; consider replacing with boolean test}} {{4-12=}} {{15-15= != nil}}
 
@@ -137,13 +166,26 @@ func testShadowing(_ a: Int?, b: Int?, c: Int?, d: Int?) {
   }
 }
 
+func testShadowingWithShorthand(_ a: Int?, b: Int?, c: Int?, d: Int?) {
+  guard let a, let b = a > 0 ? b : nil else { return }
+  _ = b
+
+  if let c, let d = c > 0 ? d : nil {
+    _ = d
+  }
+}
+
 func useInt(_ x: Int) {}
 
-func testWhileScoping(_ a: Int?) {// expected-note {{did you mean 'a'?}}
+func testWhileScoping(_ a: Int?) {
   while let x = a { }
   useInt(x) // expected-error{{cannot find 'x' in scope}}
 }
 
+func testWhileShorthand(_ b: Int?) {
+  while let b { _ = b }
+}
+
 // Matching a case with a single, labeled associated value.
 public enum SomeParseResult<T> {
   case error(length: Int)

test/stmt/statements.swift

@@ -357,7 +357,7 @@ func testMyEnumWithCaseLabels(_ a : MyEnumWithCaseLabels) {
 }
 
 
-func test_guard(_ x : Int, y : Int??, cond : Bool) {
+func test_guard(_ x : Int, y : Int??, z: Int?, cond : Bool) {
 
   // These are all ok.
   guard let a = y else {}
@@ -366,9 +366,9 @@ func test_guard(_ x : Int, y : Int??, cond : Bool) {
   guard case let c = x, cond else {}
   guard case let Optional.some(d) = y else {}
   guard x != 4, case _ = x else { }
-
-
-  guard let e, cond else {}    // expected-error {{variable binding in a condition requires an initializer}}
+  guard let z, cond else {}
+  
+  
   guard case let f? : Int?, cond else {}    // expected-error {{variable binding in a condition requires an initializer}}
 
   // FIXME: Bring back the tailored diagnostic