[diagnostics] Emit a a note for optional conversion of raw pointers. (#4442)

In CSDiag.cpp I previously added a helper, isCastToTypedPointer(), to emit an
diagnostics explaining how to migrate UnsafeRawPointer conversion. This commit
broadens that diagnostic to handle Optional<UnsafeRawPointer>.

rdar:27894255 [3.0 migration] Emit an additional note for conversion

Author: atrick

lib/Sema/CSDiag.cpp

@@ -5043,6 +5043,10 @@ static bool isCastToTypedPointer(ASTContext &Ctx, const Expr *Fn,
   if (InitType.isNull() || ArgType.isNull())
     return false;
 
+  // unwrap one level of Optional
+  if (auto ArgOptType = ArgType->getOptionalObjectType())
+    ArgType = ArgOptType;
+
   auto *InitNom = InitType->getAnyNominal();
   if (!InitNom)
     return false;

test/1_stdlib/UnsafePointerDiagnostics.swift

@@ -12,6 +12,15 @@ func unsafePointerConversionAvailability(
   umps: UnsafeMutablePointer<String>,
   ups: UnsafePointer<String>) {
 
+  let omrp: UnsafeMutableRawPointer? = mrp
+  let orp: UnsafeRawPointer? = rp
+  let oumpv: UnsafeMutablePointer<Void> = umpv  // expected-warning {{UnsafeMutablePointer<Void> has been replaced by UnsafeMutableRawPointer}}
+  let oupv: UnsafePointer<Void>? = upv  // expected-warning {{UnsafePointer<Void> has been replaced by UnsafeRawPointer}}
+  let oumpi: UnsafeMutablePointer<Int>? = umpi
+  let oupi: UnsafePointer<Int>? = upi
+  let oumps: UnsafeMutablePointer<String>? = umps
+  let oups: UnsafePointer<String>? = ups
+
   _ = UnsafeMutableRawPointer(mrp)
   _ = UnsafeMutableRawPointer(rp)   // expected-error {{'init' has been renamed to 'init(mutating:)'}}
   _ = UnsafeMutableRawPointer(umpv)
@@ -20,6 +29,14 @@ func unsafePointerConversionAvailability(
   _ = UnsafeMutableRawPointer(upi)  // expected-error {{'init' has been renamed to 'init(mutating:)'}}
   _ = UnsafeMutableRawPointer(umps)
   _ = UnsafeMutableRawPointer(ups)  // expected-error {{'init' has been renamed to 'init(mutating:)'}}
+  _ = UnsafeMutableRawPointer(omrp)
+  _ = UnsafeMutableRawPointer(orp)   // expected-error {{'init' has been renamed to 'init(mutating:)'}}
+  _ = UnsafeMutableRawPointer(oumpv)
+  _ = UnsafeMutableRawPointer(oupv)  // expected-error {{'init' has been renamed to 'init(mutating:)'}}
+  _ = UnsafeMutableRawPointer(oumpi)
+  _ = UnsafeMutableRawPointer(oupi)  // expected-error {{'init' has been renamed to 'init(mutating:)'}}
+  _ = UnsafeMutableRawPointer(oumps)
+  _ = UnsafeMutableRawPointer(oups)  // expected-error {{'init' has been renamed to 'init(mutating:)'}}
 
   // These all correctly pass with no error.
   _ = UnsafeRawPointer(mrp)
@@ -30,8 +47,15 @@ func unsafePointerConversionAvailability(
   _ = UnsafeRawPointer(upi)
   _ = UnsafeRawPointer(umps)
   _ = UnsafeRawPointer(ups)
+  _ = UnsafeRawPointer(omrp)
+  _ = UnsafeRawPointer(orp)
+  _ = UnsafeRawPointer(oumpv)
+  _ = UnsafeRawPointer(oupv)
+  _ = UnsafeRawPointer(oumpi)
+  _ = UnsafeRawPointer(oupi)
+  _ = UnsafeRawPointer(oumps)
+  _ = UnsafeRawPointer(oups)
 
-  // UnsafeMutablePointer<Void> to UnsafeMutableRawPointer(umpv)
   _ = UnsafeMutablePointer<Void>(rp) // expected-warning 3 {{UnsafeMutablePointer<Void> has been replaced by UnsafeMutableRawPointer}} expected-error {{cannot invoke initializer for type 'UnsafeMutablePointer<Void>' with an argument list of type '(UnsafeRawPointer)'}} expected-note {{overloads for 'UnsafeMutablePointer<Void>' exist with these partially matching parameter lists: (RawPointer), (OpaquePointer), (OpaquePointer?), (UnsafeMutablePointer<Pointee>), (UnsafeMutablePointer<Pointee>?)}} expected-note{{Pointer conversion restricted: use '.assumingMemoryBound(to:)' or '.bindMemory(to:capacity:)' to view memory as a type}}
   _ = UnsafeMutablePointer<Void>(mrp) // expected-error {{cannot invoke initializer for type 'UnsafeMutablePointer<Void>' with an argument list of type '(UnsafeMutableRawPointer)'}} expected-note {{}} expected-warning 3 {{UnsafeMutablePointer<Void> has been replaced by UnsafeMutableRawPointer}} expected-note{{overloads for 'UnsafeMutablePointer<Void>' exist with these partially matching parameter lists: (RawPointer), (OpaquePointer), (OpaquePointer?), (UnsafeMutablePointer<Pointee>), (UnsafeMutablePointer<Pointee>?)}}
   _ = UnsafeMutablePointer<Void>(umpv) // expected-warning {{UnsafeMutablePointer<Void> has been replaced by UnsafeMutableRawPointer}}
@@ -41,7 +65,6 @@ func unsafePointerConversionAvailability(
   _ = UnsafeMutablePointer<Void>(umps) // expected-warning {{UnsafeMutablePointer<Void> has been replaced by UnsafeMutableRawPointer}}
   _ = UnsafeMutablePointer<Void>(ups)  // expected-error {{'init' has been renamed to 'init(mutating:)'}} expected-warning {{UnsafeMutablePointer<Void> has been replaced by UnsafeMutableRawPointer}}
 
-  // UnsafePointer<Void> to UnsafeRawPointer(umpv)
   _ = UnsafePointer<Void>(rp)  // expected-error {{cannot invoke initializer for type 'UnsafePointer<Void>' with an argument list of type '(UnsafeRawPointer)'}} expected-note {{}} expected-warning 3 {{UnsafePointer<Void> has been replaced by UnsafeRawPointer}} expected-note{{overloads for 'UnsafePointer<Void>' exist with these partially matching parameter lists: (RawPointer), (OpaquePointer), (OpaquePointer?), (UnsafePointer<Pointee>), (UnsafePointer<Pointee>?), (UnsafeMutablePointer<Pointee>), (UnsafeMutablePointer<Pointee>?)}}
   _ = UnsafePointer<Void>(mrp) // expected-error {{cannot invoke initializer for type 'UnsafePointer<Void>' with an argument list of type '(UnsafeMutableRawPointer)'}} expected-note {{}} expected-warning 3 {{UnsafePointer<Void> has been replaced by UnsafeRawPointer}} expected-note{{overloads for 'UnsafePointer<Void>' exist with these partially matching parameter lists: (RawPointer), (OpaquePointer), (OpaquePointer?), (UnsafePointer<Pointee>), (UnsafePointer<Pointee>?), (UnsafeMutablePointer<Pointee>), (UnsafeMutablePointer<Pointee>?)}}
   _ = UnsafePointer<Void>(umpv) // expected-warning {{UnsafePointer<Void> has been replaced by UnsafeRawPointer}}
@@ -59,6 +82,14 @@ func unsafePointerConversionAvailability(
   _ = UnsafeMutablePointer<Int>(upi)  // expected-error {{'init' has been renamed to 'init(mutating:)'}}
   _ = UnsafeMutablePointer<Int>(umps) // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
   _ = UnsafeMutablePointer<Int>(ups)  // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
+  _ = UnsafeMutablePointer<Int>(orp) // expected-error {{cannot invoke initializer for type 'UnsafeMutablePointer<Int>' with an argument list of type '(UnsafeRawPointer?)'}} expected-note {{Pointer conversion restricted: use '.assumingMemoryBound(to:)' or '.bindMemory(to:capacity:)' to view memory as a type.}} expected-note {{}}
+  _ = UnsafeMutablePointer<Int>(omrp) // expected-error {{cannot invoke initializer for type 'UnsafeMutablePointer<Int>' with an argument list of type '(UnsafeMutableRawPointer?)'}} expected-note {{Pointer conversion restricted: use '.assumingMemoryBound(to:)' or '.bindMemory(to:capacity:)' to view memory as a type.}} expected-note {{}}
+  _ = UnsafeMutablePointer<Int>(oumpv) // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
+  _ = UnsafeMutablePointer<Int>(oupv)  // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
+  _ = UnsafeMutablePointer<Int>(oumpi)
+  _ = UnsafeMutablePointer<Int>(oupi)  // expected-error {{'init' has been renamed to 'init(mutating:)'}}
+  _ = UnsafeMutablePointer<Int>(oumps) // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
+  _ = UnsafeMutablePointer<Int>(oups)  // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
 
   _ = UnsafePointer<Int>(rp)  // expected-error {{cannot invoke initializer for type 'UnsafePointer<Int>' with an argument list of type '(UnsafeRawPointer)'}} expected-note {{Pointer conversion restricted: use '.assumingMemoryBound(to:)' or '.bindMemory(to:capacity:)' to view memory as a type.}} expected-note {{}}
   _ = UnsafePointer<Int>(mrp) // expected-error {{cannot invoke initializer for type 'UnsafePointer<Int>' with an argument list of type '(UnsafeMutableRawPointer)'}} expected-note {{Pointer conversion restricted: use '.assumingMemoryBound(to:)' or '.bindMemory(to:capacity:)' to view memory as a type.}} expected-note {{}}
@@ -68,4 +99,12 @@ func unsafePointerConversionAvailability(
   _ = UnsafePointer<Int>(upi)
   _ = UnsafePointer<Int>(umps) // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
   _ = UnsafePointer<Int>(ups)  // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
+  _ = UnsafePointer<Int>(orp)  // expected-error {{cannot invoke initializer for type 'UnsafePointer<Int>' with an argument list of type '(UnsafeRawPointer?)'}} expected-note {{Pointer conversion restricted: use '.assumingMemoryBound(to:)' or '.bindMemory(to:capacity:)' to view memory as a type.}} expected-note {{}}
+  _ = UnsafePointer<Int>(omrp) // expected-error {{cannot invoke initializer for type 'UnsafePointer<Int>' with an argument list of type '(UnsafeMutableRawPointer?)'}} expected-note {{Pointer conversion restricted: use '.assumingMemoryBound(to:)' or '.bindMemory(to:capacity:)' to view memory as a type.}} expected-note {{}}
+  _ = UnsafePointer<Int>(oumpv) // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
+  _ = UnsafePointer<Int>(oupv)  // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
+  _ = UnsafePointer<Int>(oumpi)
+  _ = UnsafePointer<Int>(oupi)
+  _ = UnsafePointer<Int>(oumps) // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
+  _ = UnsafePointer<Int>(oups)  // expected-error {{'init' is unavailable: use 'withMemoryRebound(to:capacity:_)' to temporarily view memory as another layout-compatible type.}}
 }