Fix unit tests

Author: Brian King

test/Compatibility/tuple_arguments.swift

@@ -53,10 +53,10 @@ do {
 }
 
 do {
-  var a = 3
-  var b = 4
-  var c = (3)
-  var d = (a, b)
+  var a = 3 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var c = (3) // expected-warning {{variable 'c' was never mutated; consider changing to 'let' constant}}
+  var d = (a, b) // expected-warning {{variable 'd' was never mutated; consider changing to 'let' constant}}
 
   concrete(a)
   concrete((a))
@@ -535,9 +535,9 @@ do {
 }
 
 do {
-  var a = 3
-  var b = 4
-  var c = (a, b)
+  var a = 3 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var c = (a, b) // expected-warning {{variable 'c' was never mutated; consider changing to 'let' constant}}
 
   _ = InitTwo(a, b)
   _ = InitTwo((a, b)) // expected-error {{missing argument for parameter #2 in call}}
@@ -583,9 +583,9 @@ do {
 }
 
 do {
-  var a = 3
-  var b = 4
-  var d = (a, b)
+  var a = 3 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var d = (a, b) // expected-warning {{variable 'd' was never mutated; consider changing to 'let' constant}}
 
   var s1 = SubscriptTwo()
   _ = s1[a, b]
@@ -952,9 +952,9 @@ do {
 }
 
 do {
-  var a = 3
-  var b = 4
-  var c = (a, b)
+  var a = 3 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var c = (a, b) // expected-warning {{variable 'c' was never mutated; consider changing to 'let' constant}}
 
   // _ = GenericInit<(Int, Int)>(a, b) // Crashes in Swift 3
   _ = GenericInit<(Int, Int)>((a, b)) // expected-error {{expression type 'GenericInit<(Int, Int)>' is ambiguous without more context}}
@@ -1017,9 +1017,9 @@ do {
 }
 
 do {
-  var a = 3.0
-  var b = 4.0
-  var d = (a, b)
+  var a = 3.0 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4.0 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var d = (a, b) // expected-warning {{variable 'd' was never mutated; consider changing to 'let' constant}}
 
   var s1 = GenericSubscript<(Double, Double)>()
   _ = s1[a, b]

test/Constraints/tuple_arguments.swift

@@ -37,10 +37,10 @@ do {
 }
 
 do {
-  var a = 3
-  var b = 4
-  var c = (3)
-  var d = (a, b)
+  var a = 3 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var c = (3) // expected-warning {{variable 'c' was never mutated; consider changing to 'let' constant}}
+  var d = (a, b) // expected-warning {{variable 'd' was never mutated; consider changing to 'let' constant}}
 
   concrete(a)
   concrete((a))
@@ -520,9 +520,9 @@ do {
 }
 
 do {
-  var a = 3
-  var b = 4
-  var c = (a, b)
+  var a = 3 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var c = (a, b) // expected-warning {{variable 'c' was never mutated; consider changing to 'let' constant}}
 
   _ = InitTwo(a, b)
   _ = InitTwo((a, b)) // expected-error {{missing argument for parameter #2 in call}}
@@ -568,9 +568,9 @@ do {
 }
 
 do {
-  var a = 3
-  var b = 4
-  var d = (a, b)
+  var a = 3 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var d = (a, b) // expected-warning {{variable 'd' was never mutated; consider changing to 'let' constant}}
 
   var s1 = SubscriptTwo()
   _ = s1[a, b]
@@ -937,9 +937,9 @@ do {
 }
 
 do {
-  var a = 3
-  var b = 4
-  var c = (a, b)
+  var a = 3 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var c = (a, b) // expected-warning {{variable 'c' was never mutated; consider changing to 'let' constant}}
 
   _ = GenericInit<(Int, Int)>(a, b) // expected-error {{extra argument in call}}
   _ = GenericInit<(Int, Int)>((a, b))
@@ -1002,9 +1002,9 @@ do {
 }
 
 do {
-  var a = 3.0
-  var b = 4.0
-  var d = (a, b)
+  var a = 3.0 // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}}
+  var b = 4.0 // expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
+  var d = (a, b) // expected-warning {{variable 'd' was never mutated; consider changing to 'let' constant}}
 
   var s1 = GenericSubscript<(Double, Double)>()
   _ = s1[a, b] // expected-error {{extra argument in call}}

test/Parse/availability_query.swift

@@ -97,7 +97,7 @@ if 1 != 2, #available(iOS 8.0, *) {}
 
 // Pattern then #available(iOS 8.0, *) {
 if case 42 = 42, #available(iOS 8.0, *) {}
-if let x = Optional(42), #available(iOS 8.0, *) {}
+if let _ = Optional(42), #available(iOS 8.0, *) {}
 
 // Allow "macOS" as well.
 if #available(macOS 10.51, *) {

test/Parse/matching_patterns.swift

@@ -47,13 +47,12 @@ case 1 + (_): // expected-error{{'_' can only appear in a pattern or on the left
 }
 
 switch (x,x) {
-case (var a, var a): // expected-error {{definition conflicts with previous value}} expected-note {{previous definition of 'a' is here}}
+case (var a, var a): // expected-error {{definition conflicts with previous value}} expected-note {{previous definition of 'a' is here}} expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}} expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}}
   fallthrough
 case _:
   ()
 }
 
-
 var e : Any = 0
 
 switch e {

test/Parse/switch.swift

@@ -197,28 +197,28 @@ default:
 var t = (1, 2)
 
 switch t {
-case (var a, 2), (1, _): // expected-error {{'a' must be bound in every pattern}}
+case (var a, 2), (1, _): // expected-error {{'a' must be bound in every pattern}} expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}}
   ()
 
 case (_, 2), (var a, _): // expected-error {{'a' must be bound in every pattern}}
   ()
 
-case (var a, 2), (1, var b): // expected-error {{'a' must be bound in every pattern}} expected-error {{'b' must be bound in every pattern}}
+case (var a, 2), (1, var b): // expected-error {{'a' must be bound in every pattern}} expected-error {{'b' must be bound in every pattern}} expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}}
   ()
 
-case (var a, 2): // expected-error {{'case' label in a 'switch' should have at least one executable statement}} {{17-17= break}}
+case (var a, 2): // expected-error {{'case' label in a 'switch' should have at least one executable statement}} {{17-17= break}} expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}}
 case (1, _):
   ()
 
 case (_, 2): // expected-error {{'case' label in a 'switch' should have at least one executable statement}} {{13-13= break}}
-case (1, var a):
+case (1, var a): // expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}}
   ()
 
-case (var a, 2): // expected-error {{'case' label in a 'switch' should have at least one executable statement}} {{17-17= break}}
-case (1, var b):
+case (var a, 2): // expected-error {{'case' label in a 'switch' should have at least one executable statement}} {{17-17= break}} expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}}
+case (1, var b): // expected-warning {{variable 'b' was never used; consider replacing with '_' or removing it}}
   ()
 
-case (1, let b): // let bindings
+case (1, let b): // let bindings expected-warning {{immutable value 'b' was never used; consider replacing with '_' or removing it}}
   ()
 
 case (_, 2), (let a, _): // expected-error {{'a' must be bound in every pattern}}
@@ -228,10 +228,10 @@ case (_, 2), (let a, _): // expected-error {{'a' must be bound in every pattern}
 case (_, 2), (1, _):
   ()
 
-case (_, var a), (_, var a):
+case (_, var a), (_, var a): // expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}}
   ()
 
-case (var a, var b), (var b, var a):
+case (var a, var b), (var b, var a): // expected-warning {{variable 'a' was never used; consider replacing with '_' or removing it}} expected-warning {{variable 'b' was never used; consider replacing with '_' or removing it}}
   ()
 
 case (_, 2): // expected-error {{'case' label in a 'switch' should have at least one executable statement}} {{13-13= break}}
@@ -251,7 +251,7 @@ func patternVarUsedInAnotherPattern(x: Int) {
 switch t {
 case (1, 2):
   fallthrough // expected-error {{'fallthrough' cannot transfer control to a case label that declares variables}}
-case (var a, var b):
+case (var a, var b): // expected-warning {{variable 'a' was never mutated; consider changing to 'let' constant}} expected-warning {{variable 'b' was never mutated; consider changing to 'let' constant}}
   t = (b, a)
 }
 

test/decl/func/throwing_functions.swift

@@ -117,7 +117,7 @@ var c4 : () -> Int = {() throws -> Int in 0} // expected-error{{invalid conversi
 var c5 : () -> Int = { try c2() } // expected-error{{invalid conversion from throwing function of type '() throws -> Int' to non-throwing function type '() -> Int'}}
 var c6 : () throws -> Int = { do { _ = try c2() } ; return 0 }
 var c7 : () -> Int = { do { try c2() } ; return 0 } // expected-error{{invalid conversion from throwing function of type '() throws -> _' to non-throwing function type '() -> Int'}}
-var c8 : () -> Int = { do { _ = try c2()  } catch _ { var x = 0 } ; return 0 }
+var c8 : () -> Int = { do { _ = try c2()  } catch _ { var x = 0 } ; return 0 } // expected-warning {{initialization of variable 'x' was never used; consider replacing with assignment to '_' or removing it}}
 var c9 : () -> Int = { do { try c2()  } catch Exception.A { var x = 0 } ; return 0 }// expected-error{{invalid conversion from throwing function of type '() throws -> _' to non-throwing function type '() -> Int'}}
 var c10 : () -> Int = { throw Exception.A; return 0 } // expected-error{{invalid conversion from throwing function of type '() throws -> _' to non-throwing function type '() -> Int'}}
 var c11 : () -> Int = { try! c2() }

test/decl/var/usage.swift

@@ -253,18 +253,18 @@ func test2() {
   let (d): Int = 9 // expected-warning {{immutable value 'd' was never used; consider replacing with '_' or removing it}} {{8-9=_}}
 }
 
-for i in 0..<10 { // expected-warning {{immutable value 'i' was never used; consider replacing with '_' or removing it}} {{5-6=_}}
-   print("")
-}
-
-// Due to the complexities of global variable tracing, these will not generate warnings
-let unusedVariable = ""
-var unNeededVar = false
-if unNeededVar {}
-
 let optionalString: String? = "check"
 if let string = optionalString {}  // expected-warning {{value 'string' was defined but never used; consider replacing with boolean test}} {{4-17=}} {{31-31= != nil}}
 
 let optionalAny: Any? = "check"
 if let string = optionalAny as? String {} // expected-warning {{value 'string' was defined but never used; consider replacing with boolean test}} {{4-17=(}} {{39-39=) != nil}}
 
+// Due to the complexities of global variable tracing, these will not generate warnings
+let unusedVariable = ""
+var unNeededVar = false
+if unNeededVar {}
+guard let foo = optionalAny else {}
+
+for i in 0..<10 { // expected-warning {{immutable value 'i' was never used; consider replacing with '_' or removing it}} {{5-6=_}}
+   print("")
+}

test/decl/var/variables.swift

@@ -48,6 +48,7 @@ var aot2 = aot1          // expected-warning {{variable 'aot2' inferred to have
 
 
 for item in [AnyObject]() {  // No warning in for-each loop.
+  _ = item
 }
 
 
@@ -99,6 +100,7 @@ func test21081340() {
 if true {
   let s : Int
   s = 42  // should be valid.
+  _ = s
 }
 
 

test/expr/cast/array_iteration.swift

@@ -12,7 +12,7 @@ rootView.subviews = v
 
 _ = rootView.subviews as! [View]
 
-for view in rootView.subviews as! [View] {
+for view in rootView.subviews as! [View] { // expected-warning{{immutable value 'view' was never used; consider replacing with '_' or removing it}}
   doFoo()
 }
 
@@ -32,18 +32,18 @@ _ = ao as! [View] // works
 
 var b = Array<(String, Int)>()
 
-for x in b {
+for x in b { // expected-warning{{immutable value 'x' was never used; consider replacing with '_' or removing it}}
   doFoo()
 }
 
 var c : Array<(String, Int)>! = Array()
 
-for x in c {
+for x in c { // expected-warning{{immutable value 'x' was never used; consider replacing with '_' or removing it}}
   doFoo()
 }
 
 var d : Array<(String, Int)>? = Array()
 
-for x in d! {
+for x in d! { // expected-warning{{immutable value 'x' was never used; consider replacing with '_' or removing it}}
   doFoo()
 }

test/expr/cast/as_coerce.swift

@@ -55,6 +55,7 @@ if cc is P {
 }
 if let p = cc as? P {
   doFoo()
+  _ = p
 }
 
 // Test that 'as?' coercion fails.

test/stmt/if_while_var.swift

@@ -57,8 +57,8 @@ if let x = foo() {
 
 var opt: Int? = .none
 
-if let x = opt {}
-if var x = opt {}
+if let x = opt {} // expected-warning {{value 'x' was defined but never used; consider replacing with boolean test}}
+if var x = opt {} // expected-warning {{value 'x' was defined but never used; consider replacing with boolean test}}
 
 // <rdar://problem/20800015> Fix error message for invalid if-let
 let someInteger = 1
@@ -67,21 +67,21 @@ if case let y? = someInteger {}  // expected-error {{'?' pattern cannot match va
 
 // Test multiple clauses on "if let".
 if let x = opt, let y = opt, x != y,
-   let a = opt, var b = opt {
+   let a = opt, var b = opt { // expected-warning {{immutable value 'a' was never used; consider replacing with '_' or removing it}} expected-warning {{variable 'b' was never used; consider replacing with '_' or removing it}}
 }
 
 // Leading boolean conditional.
 if 1 != 2, let x = opt,
    y = opt,  // expected-error {{expected 'let' in conditional}} {{4-4=let }}
    x != y,
-   let a = opt, var b = opt {
+   let a = opt, var b = opt { // expected-warning {{immutable value 'a' was never used; consider replacing with '_' or removing it}} expected-warning {{variable 'b' was never used; consider replacing with '_' or removing it}}
 }
 
 // <rdar://problem/20457938> typed pattern is not allowed on if/let condition
-if 1 != 2, let x : Int? = opt {}
+if 1 != 2, let x : Int? = opt {} // expected-warning {{immutable value 'x' was never used; consider replacing with '_' or removing it}}
 // expected-warning @-1 {{explicitly specified type 'Int?' adds an additional level of optional to the initializer, making the optional check always succeed}} {{20-26=Int}}
 
-if 1 != 2, case let x? : Int? = 42 {}
+if 1 != 2, case let x? : Int? = 42 {} // expected-warning {{immutable value 'x' was never used; consider replacing with '_' or removing it}}
 // expected-warning @-1 {{non-optional expression of type 'Int' used in a check for optionals}}
 
 
@@ -91,7 +91,7 @@ if 1 != 2, case let x? : Int? = 42 {}
 if 1 != 2, { // expected-error {{'() -> ()' is not convertible to 'Bool'}}
 } // expected-error {{expected '{' after 'if' condition}}
 if 1 != 2, 4 == 57 {}
-if 1 != 2, 4 == 57, let x = opt {}
+if 1 != 2, 4 == 57, let x = opt {} // expected-warning {{immutable value 'x' was never used; consider replacing with '_' or removing it}}
 
 // Test that these don't cause the parser to crash.
 if true { if a == 0; {} }   // expected-error {{expected '{' after 'if' condition}} expected-error 3{{}}