[Diagnostics][NFC] Add support for using the %select format specifier with StringRef args

Get rid of some redundant availability diagnostics as a result.

Author: owenv

docs/Diagnostics.md

@@ -97,7 +97,7 @@ Most diagnostics have no reason to change behavior under editor mode. An example
 
 - `%0`, `%1`, etc - Formats the specified diagnostic argument based on its type.
 
-- `%select{a|b|c}0` - Chooses from a list of alternatives, separated by vertical bars, based on the value of the given argument. In this example, a value of 2 in diagnostic argument 0 would result in "c" being output.
+- `%select{a|b|c}0` - Chooses from a list of alternatives, separated by vertical bars, based on the value of the given argument. In this example, a value of 2 in diagnostic argument 0 would result in "c" being output. The argument to the %select may be an integer, enum, or StringRef. If it's a StringRef, the specifier acts as an emptiness check.
 
 - `%s0` - Produces an "s" if the given argument is anything other than 1, as meant for an English plural. This isn't particularly localizable without a more general `%plural` form, but most diagnostics try to avoid cases where a plural/singular distinction would be necessary in the first place.
 

include/swift/AST/DiagnosticsSema.def

@@ -2223,10 +2223,8 @@ ERROR(multiple_override,none,
 NOTE(multiple_override_prev,none,
      "%0 previously overridden here", (DeclName))
 
-ERROR(override_unavailable,none,
-      "cannot override %0 which has been marked unavailable", (DeclBaseName))
-ERROR(override_unavailable_msg, none,
-      "cannot override %0 which has been marked unavailable: %1",
+ERROR(override_unavailable, none,
+      "cannot override %0 which has been marked unavailable%select{|: %1}1",
       (DeclBaseName, StringRef))
 
 ERROR(override_less_available,none,
@@ -4118,27 +4116,16 @@ ERROR(dynamic_replacement_replaced_constructor_is_not_convenience, none,
 
 ERROR(availability_decl_unavailable, none,
       "%select{getter for |setter for |}0%1 is unavailable"
-      "%select{ in %3|}2",
-      (unsigned, DeclName, bool, StringRef))
+      "%select{ in %3|}2%select{|: %4}4",
+      (unsigned, DeclName, bool, StringRef, StringRef))
 
 #define REPLACEMENT_DECL_KIND_SELECT "select{| instance method| property}"
 ERROR(availability_decl_unavailable_rename, none,
       "%select{getter for |setter for |}0%1 has been "
       "%select{renamed to|replaced by}2%" REPLACEMENT_DECL_KIND_SELECT "3 "
-      "'%4'",
-      (unsigned, DeclName, bool, unsigned, StringRef))
-
-ERROR(availability_decl_unavailable_rename_msg, none,
-      "%select{getter for |setter for |}0%1 has been "
-      "%select{renamed to|replaced by}2%" REPLACEMENT_DECL_KIND_SELECT "3 "
-      "'%4': %5",
+      "'%4'%select{|: %5}5",
       (unsigned, DeclName, bool, unsigned, StringRef, StringRef))
 
-ERROR(availability_decl_unavailable_msg, none,
-      "%select{getter for |setter for |}0%1 is unavailable"
-      "%select{ in %3|}2: %4",
-      (unsigned, DeclName, bool, StringRef, StringRef))
-
 NOTE(availability_marked_unavailable, none,
      "%select{getter for |setter for |}0%1 has been explicitly marked "
      "unavailable here", (unsigned, DeclName))
@@ -4153,12 +4140,7 @@ NOTE(availability_obsoleted, none,
 
 WARNING(availability_deprecated, none,
         "%select{getter for |setter for |}0%1 %select{is|%select{is|was}4}2 "
-        "deprecated%select{| in %3%select{| %5}4}2",
-        (unsigned, DeclName, bool, StringRef, bool, llvm::VersionTuple))
-
-WARNING(availability_deprecated_msg, none,
-        "%select{getter for |setter for |}0%1 %select{is|%select{is|was}4}2 "
-        "deprecated%select{| in %3%select{| %5}4}2: %6",
+        "deprecated%select{| in %3%select{| %5}4}2%select{|: %6}6",
         (unsigned, DeclName, bool, StringRef, bool, llvm::VersionTuple,
          StringRef))
 

lib/AST/DiagnosticEngine.cpp

@@ -449,8 +449,14 @@ static void formatDiagnosticArgument(StringRef Modifier,
     break;
 
   case DiagnosticArgumentKind::String:
-    assert(Modifier.empty() && "Improper modifier for string argument");
-    Out << Arg.getAsString();
+    if (Modifier == "select") {
+      formatSelectionArgument(ModifierArguments, Args,
+                              Arg.getAsString().empty() ? 0 : 1, FormatOpts,
+                              Out);
+    } else {
+      assert(Modifier.empty() && "Improper modifier for string argument");
+      Out << Arg.getAsString();
+    }
     break;
 
   case DiagnosticArgumentKind::Identifier:

lib/Sema/TypeCheckAvailability.cpp

@@ -1955,8 +1955,9 @@ void TypeChecker::diagnoseIfDeprecated(SourceRange ReferenceRange,
   if (Attr->Message.empty() && Attr->Rename.empty()) {
     diagnose(ReferenceRange.Start, diag::availability_deprecated,
              RawAccessorKind, Name, Attr->hasPlatform(), Platform,
-             Attr->Deprecated.hasValue(), DeprecatedVersion)
-      .highlight(Attr->getRange());
+             Attr->Deprecated.hasValue(), DeprecatedVersion,
+             /*message*/ StringRef())
+        .highlight(Attr->getRange());
     return;
   }
 
@@ -1967,11 +1968,11 @@ void TypeChecker::diagnoseIfDeprecated(SourceRange ReferenceRange,
 
   if (!Attr->Message.empty()) {
     EncodedDiagnosticMessage EncodedMessage(Attr->Message);
-    diagnose(ReferenceRange.Start, diag::availability_deprecated_msg,
+    diagnose(ReferenceRange.Start, diag::availability_deprecated,
              RawAccessorKind, Name, Attr->hasPlatform(), Platform,
              Attr->Deprecated.hasValue(), DeprecatedVersion,
              EncodedMessage.Message)
-      .highlight(Attr->getRange());
+        .highlight(Attr->getRange());
   } else {
     unsigned rawReplaceKind = static_cast<unsigned>(
         replacementDeclKind.getValueOr(ReplacementDeclKind::None));
@@ -1998,12 +1999,9 @@ void swift::diagnoseUnavailableOverride(ValueDecl *override,
   ASTContext &ctx = override->getASTContext();
   auto &diags = ctx.Diags;
   if (attr->Rename.empty()) {
-    if (attr->Message.empty())
-      diags.diagnose(override, diag::override_unavailable,
-                     override->getBaseName());
-    else
-      diags.diagnose(override, diag::override_unavailable_msg,
-                     override->getBaseName(), attr->Message);
+    EncodedDiagnosticMessage EncodedMessage(attr->Message);
+    diags.diagnose(override, diag::override_unavailable,
+                   override->getBaseName(), EncodedMessage.Message);
 
     DeclName name;
     unsigned rawAccessorKind;
@@ -2185,22 +2183,12 @@ bool swift::diagnoseExplicitUnavailability(
     unsigned rawReplaceKind = static_cast<unsigned>(
         replaceKind.getValueOr(ReplacementDeclKind::None));
     StringRef newName = replaceKind ? newNameBuf.str() : Attr->Rename;
-
-    if (Attr->Message.empty()) {
-      auto diag = diags.diagnose(Loc,
-                                 diag::availability_decl_unavailable_rename,
-                                 RawAccessorKind, Name,
-                                 replaceKind.hasValue(),
-                                 rawReplaceKind, newName);
-      attachRenameFixIts(diag);
-    } else {
       EncodedDiagnosticMessage EncodedMessage(Attr->Message);
       auto diag =
-        diags.diagnose(Loc, diag::availability_decl_unavailable_rename_msg,
-                       RawAccessorKind, Name, replaceKind.hasValue(),
-                       rawReplaceKind, newName, EncodedMessage.Message);
+          diags.diagnose(Loc, diag::availability_decl_unavailable_rename,
+                         RawAccessorKind, Name, replaceKind.hasValue(),
+                         rawReplaceKind, newName, EncodedMessage.Message);
       attachRenameFixIts(diag);
-    }
   } else if (isSubscriptReturningString(D, ctx)) {
     diags.diagnose(Loc, diag::availabilty_string_subscript_migration)
       .highlight(R)
@@ -2209,16 +2197,12 @@ bool swift::diagnoseExplicitUnavailability(
 
     // Skip the note emitted below.
     return true;
-  } else if (Attr->Message.empty()) {
-    diags.diagnose(Loc, diag::availability_decl_unavailable,
-                   RawAccessorKind, Name, platform.empty(), platform)
-      .highlight(R);
   } else {
     EncodedDiagnosticMessage EncodedMessage(Attr->Message);
-    diags.diagnose(Loc, diag::availability_decl_unavailable_msg,
-                   RawAccessorKind, Name, platform.empty(), platform,
-                   EncodedMessage.Message)
-      .highlight(R);
+    diags
+        .diagnose(Loc, diag::availability_decl_unavailable, RawAccessorKind,
+                  Name, platform.empty(), platform, EncodedMessage.Message)
+        .highlight(R);
   }
 
   switch (Attr->getVersionAvailability(ctx)) {
@@ -2695,7 +2679,7 @@ AvailabilityWalker::diagnoseIncDecRemoval(const ValueDecl *D, SourceRange R,
     std::tie(RawAccessorKind, Name) = getAccessorKindAndNameForDiagnostics(D);
 
     // If we emit a deprecation diagnostic, produce a fixit hint as well.
-    auto diag = TC.diagnose(R.Start, diag::availability_decl_unavailable_msg,
+    auto diag = TC.diagnose(R.Start, diag::availability_decl_unavailable,
                             RawAccessorKind, Name, true, "",
                             "it has been removed in Swift 3");
     if (isa<PrefixUnaryExpr>(call)) {
@@ -2746,9 +2730,9 @@ AvailabilityWalker::diagnoseMemoryLayoutMigration(const ValueDecl *D,
   std::tie(RawAccessorKind, Name) = getAccessorKindAndNameForDiagnostics(D);
 
   EncodedDiagnosticMessage EncodedMessage(Attr->Message);
-  auto diag = TC.diagnose(R.Start, diag::availability_decl_unavailable_msg,
-                          RawAccessorKind, Name, true, "",
-                          EncodedMessage.Message);
+  auto diag =
+      TC.diagnose(R.Start, diag::availability_decl_unavailable, RawAccessorKind,
+                  Name, true, "", EncodedMessage.Message);
   diag.highlight(R);
 
   auto subject = args->getSubExpr();

lib/Sema/TypeCheckPattern.cpp

@@ -1414,11 +1414,11 @@ bool TypeChecker::coercePatternToType(Pattern *&P, TypeResolution resolution,
                 EEP->getName().str() == "Some") {
               SmallString<4> Rename;
               camel_case::toLowercaseWord(EEP->getName().str(), Rename);
-              diagnose(EEP->getLoc(),
-                       diag::availability_decl_unavailable_rename,
-                       /*"getter" prefix*/2, EEP->getName(), /*replaced*/false,
-                       /*special kind*/0, Rename.str())
-                .fixItReplace(EEP->getLoc(), Rename.str());
+              diagnose(
+                  EEP->getLoc(), diag::availability_decl_unavailable_rename,
+                  /*"getter" prefix*/ 2, EEP->getName(), /*replaced*/ false,
+                  /*special kind*/ 0, Rename.str(), /*message*/ StringRef())
+                  .fixItReplace(EEP->getLoc(), Rename.str());
 
               return true;
             }