Add an API to construct an XcodeSDK from an SDK type.

[aprantl]

Summary

Unfortunately I discovered that I do need to be able to go full round-trip in swift-lldb.

Also, this moves numSDKs out of the actual enum, as to not mess with the switch-cases-covered warning.

[vsk]

lldb/source/Utility/XcodeSDK.cpp

44

I'd expect -Wcovered-switch to break the build if a new case gets added and this list isn't updated. Wdyt of dropping numSDKTypes and using an llvm_unreachable here instead?

[aprantl]

Remove redundant static_assert. It was only needed in the other function because that one used cascading ifs.

[aprantl]

(Upload the full patch)

[JDevlieghere]

lldb/source/Utility/XcodeSDK.cpp

147

Cool :P

lldb/include/lldb/Utility/XcodeSDK.h

 
 namespace lldb_private {
 
 /// An abstraction for Xcode-style SDKs that works like \ref ArchSpec.
 class XcodeSDK {
   std::string m_name;
 
 public:
-  XcodeSDK() = default;
-  /// Initialize an XcodeSDK object with an SDK name. The SDK name is the last
-  /// directory component of a path one would pass to clang's -isysroot
-  /// parameter. For example, "MacOSX.10.14.sdk".
-  XcodeSDK(std::string &&name) : m_name(std::move(name)) {}
-  static XcodeSDK GetAnyMacOS() { return XcodeSDK("MacOSX.sdk"); }
-
+  /// Different types of Xcode SDKs.
   enum Type : int {
     MacOSX = 0,
     iPhoneSimulator,
     iPhoneOS,
     AppleTVSimulator,
     AppleTVOS,
     WatchSimulator,
     watchOS,
     bridgeOS,
     Linux,
-    numSDKTypes,
     unknown = -1
   };
-
-  /// The merge function follows a strict order to maintain monotonicity:
-  /// 1. SDK with the higher SDKType wins.
-  /// 2. The newer SDK wins.
-  void Merge(XcodeSDK other);
-
-  XcodeSDK &operator=(XcodeSDK other);
-  XcodeSDK(const XcodeSDK&) = default;
-  bool operator==(XcodeSDK other);
+  static constexpr int numSDKTypes = Linux + 1;
 
   /// A parsed SDK directory name.
   struct Info {
     Type type = unknown;
     llvm::VersionTuple version;
     bool internal = false;
 
     Info() = default;
     bool operator<(const Info &other) const;
+    bool operator==(const Info &other) const;
   };
 
+
+  /// Default constructor, constructs an empty string.
+  XcodeSDK() = default;
+  /// Construct an XcodeSDK object from a specification.
+  XcodeSDK(Info info);
+  /// Initialize an XcodeSDK object with an SDK name. The SDK name is the last
+  /// directory component of a path one would pass to clang's -isysroot
+  /// parameter. For example, "MacOSX.10.14.sdk".
+  XcodeSDK(std::string &&name) : m_name(std::move(name)) {}
+  static XcodeSDK GetAnyMacOS() { return XcodeSDK("MacOSX.sdk"); }
+
+  /// The merge function follows a strict order to maintain monotonicity:
+  /// 1. SDK with the higher SDKType wins.
+  /// 2. The newer SDK wins.
+  void Merge(XcodeSDK other);
+
+  XcodeSDK &operator=(XcodeSDK other);
+  XcodeSDK(const XcodeSDK&) = default;
+  bool operator==(XcodeSDK other);
+
   /// Return parsed SDK type and version number.
   Info Parse() const;
   bool IsAppleInternalSDK() const;
   llvm::VersionTuple GetVersion() const;
   Type GetType() const;
   llvm::StringRef GetString() const;
   /// Whether this Xcode SDK supports Swift.
   bool SupportsSwift() const;

lldb/source/Utility/XcodeSDK.cpp

 
 #include "llvm/ADT/Triple.h"
 
 #include <string>
 
 using namespace lldb;
 using namespace lldb_private;
 
+static llvm::StringRef GetName(XcodeSDK::Type type) {
+  switch (type) {
+  case XcodeSDK::MacOSX:
+    return "MacOSX";
+  case XcodeSDK::iPhoneSimulator:
+    return "iPhoneSimulator";
+  case XcodeSDK::iPhoneOS:
+    return "iPhoneOS";
+  case XcodeSDK::AppleTVSimulator:
+    return "AppleTVSimulator";
+  case XcodeSDK::AppleTVOS:
+    return "AppleTVOS";
+  case XcodeSDK::WatchSimulator:
+    return "WatchSimulator";
+  case XcodeSDK::watchOS:
+    return "WatchOS";
+  case XcodeSDK::bridgeOS:
+    return "bridgeOS";
+  case XcodeSDK::Linux:
+    return "Linux";
+  case XcodeSDK::unknown:
+    return {};
+  }
+  static_assert(XcodeSDK::Linux == XcodeSDK::numSDKTypes - 1,
+                "New SDK type was added, update this list!");
+}
+
+XcodeSDK::XcodeSDK(XcodeSDK::Info info) : m_name(GetName(info.type).str()) {
+  if (!m_name.empty()) {
+    if (!info.version.empty())
+      m_name += info.version.getAsString();
+    if (info.internal)
+      m_name += ".Internal";
+    m_name += ".sdk";
+  }
+}
+
 XcodeSDK &XcodeSDK::operator=(XcodeSDK other) {
   m_name = other.m_name;
   return *this;
 }
 
 bool XcodeSDK::operator==(XcodeSDK other) {
   return m_name == other.m_name;
 }
static llvm::VersionTuple ParseSDKVersion(llvm::StringRef &name) {
 
   llvm::VersionTuple version;
   version.tryParse(name.slice(0, i - 1));
   name = name.drop_front(i);
   return version;
 }
 
 static bool ParseAppleInternalSDK(llvm::StringRef &name) {
-  return name.consume_front("Internal.");
+  return name.consume_front("Internal.") || name.consume_front(".Internal.");
 }
 
 XcodeSDK::Info XcodeSDK::Parse() const {
   XcodeSDK::Info info;
   llvm::StringRef input(m_name);
   info.type = ParseSDKName(input);
   info.version = ParseSDKVersion(input);
   info.internal = ParseAppleInternalSDK(input);

 }
 
 llvm::StringRef XcodeSDK::GetString() const { return m_name; }
 
 bool XcodeSDK::Info::operator<(const Info &other) const {
   return std::tie(type, version, internal) <
          std::tie(other.type, other.version, other.internal);
 }
+
+bool XcodeSDK::Info::operator==(const Info &other) const {
+  return std::tie(type, version, internal) ==
+         std::tie(other.type, other.version, other.internal);
+}
+
 void XcodeSDK::Merge(XcodeSDK other) {
   // The "bigger" SDK always wins.
   auto l = Parse();
   auto r = other.Parse();
   if (l < r)
     *this = other;
   else {
     // The Internal flag always wins.
case watchOS:
     name = "watchos";
     break;
   case bridgeOS:
     name = "bridgeos";
     break;
   case Linux:
     name = "linux";
     break;
-  case numSDKTypes:
   case unknown:
     return {};
   }
   if (!info.version.empty())
     name += info.version.getAsString();
   if (info.internal)
     name += ".internal";
   return name;

lldb/unittests/Utility/XcodeSDKTest.cpp

TEST(XcodeSDKTest, SDKSupportsSwift) {
   EXPECT_FALSE(XcodeSDK("iPhoneSimulator7.2.sdk").SupportsSwift());
   EXPECT_TRUE(XcodeSDK("MacOSX10.10.sdk").SupportsSwift());
   EXPECT_FALSE(XcodeSDK("MacOSX10.9.sdk").SupportsSwift());
   EXPECT_TRUE(XcodeSDK("Linux.sdk").SupportsSwift());
   EXPECT_TRUE(XcodeSDK("MacOSX.sdk").SupportsSwift());
   EXPECT_FALSE(XcodeSDK("EverythingElse.sdk").SupportsSwift());
 }
 
-TEST(XcodeSDKTest, GetCanonicalName) {
+TEST(XcodeSDKTest, GetCanonicalNameAndConstruct) {
   XcodeSDK::Info info;
   info.type = XcodeSDK::Type::MacOSX;
   EXPECT_EQ("macosx", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::iPhoneSimulator;
   EXPECT_EQ("iphonesimulator", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::iPhoneOS;
   EXPECT_EQ("iphoneos", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::AppleTVSimulator;
   EXPECT_EQ("appletvsimulator", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::AppleTVOS;
   EXPECT_EQ("appletvos", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::WatchSimulator;
   EXPECT_EQ("watchsimulator", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::watchOS;
   EXPECT_EQ("watchos", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::Linux;
   EXPECT_EQ("linux", XcodeSDK::GetCanonicalName(info));
-
-  info.type = XcodeSDK::Type::numSDKTypes;
-  EXPECT_EQ("", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::unknown;
   EXPECT_EQ("", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.internal = true;
   info.type = XcodeSDK::Type::MacOSX;
   EXPECT_EQ("macosx.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::iPhoneSimulator;
   EXPECT_EQ("iphonesimulator.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::iPhoneOS;
   EXPECT_EQ("iphoneos.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::AppleTVSimulator;
   EXPECT_EQ("appletvsimulator.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::AppleTVOS;
   EXPECT_EQ("appletvos.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::WatchSimulator;
   EXPECT_EQ("watchsimulator.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::watchOS;
   EXPECT_EQ("watchos.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::MacOSX;
   info.version = llvm::VersionTuple(10, 9);
   EXPECT_EQ("macosx10.9.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 
   info.type = XcodeSDK::Type::iPhoneOS;
   info.version = llvm::VersionTuple(7, 0);
   EXPECT_EQ("iphoneos7.0.internal", XcodeSDK::GetCanonicalName(info));
+  EXPECT_EQ(XcodeSDK(info).Parse(), info);
 }
 
 TEST(XcodeSDKTest, GetSDKTypeForTriple) {
   EXPECT_EQ(
       XcodeSDK::GetSDKTypeForTriple(llvm::Triple("x86_64-apple-macosx10.14")),
       XcodeSDK::Type::MacOSX);
   EXPECT_EQ(XcodeSDK::GetSDKTypeForTriple(llvm::Triple("x86_64-apple-darwin")),
             XcodeSDK::Type::MacOSX);