Parse: Broaden an availability spec diagnostic.

The "can't be combined with shorthand specification" diagnostic doesn't need to
be specific to platform availability attributes.

Author: tshortli

lib/Parse/ParseStmt.cpp

@@ -1542,9 +1542,7 @@ Parser::parseAvailabilitySpecList(SmallVectorImpl<AvailabilitySpec *> &Specs,
           // If this was preceded by a single platform version constraint, we
           // can guess that the intention was to treat it as 'introduced' and
           // suggest a fix-it to combine them.
-          if (Specs.size() == 1 &&
-              Previous->getPlatform() != PlatformKind::none &&
-              Text != "introduced") {
+          if (Specs.size() == 1 && Text != "introduced") {
             auto PlatformNameEndLoc = Lexer::getLocForEndOfToken(
                 SourceManager, Previous->getStartLoc());
 

test/Parse/diagnose_availability.swift

@@ -64,6 +64,12 @@ func swiftDeprecatedObsoleted() {}
 // expected-warning@-1 {{expected 'introduced', 'deprecated', or 'obsoleted' in 'available' attribute for platform 'swift'}}
 func swiftMessage() {}
 
+@available(swift 5, deprecated: 6)
+// expected-error@-1 {{'deprecated' can't be combined with shorthand specification 'swift 5'}}
+// expected-note@-2 {{did you mean to specify an introduction version?}} {{17-17=, introduced:}}
+// expected-error@-3 {{expected declaration}}
+func swiftShorthandFollowedByDeprecated() {}
+
 @available(*, unavailable, message: "\("message")")
 // expected-error@-1{{'message' cannot be an interpolated string literal}}
 func interpolatedMessage() {}