[ASTGen] Generate MagicIdentifierLiteralExpr

Author: rintaro

include/swift/AST/ASTBridging.h

@@ -1765,6 +1765,23 @@ BridgedMacroExpansionExpr BridgedMacroExpansionExpr_createParsed(
     BridgedSourceLoc cLeftAngleLoc, BridgedArrayRef cGenericArgs,
     BridgedSourceLoc cRightAngleLoc, BridgedNullableArgumentList cArgList);
 
+enum ENUM_EXTENSIBILITY_ATTR(open) BridgedMagicIdentifierLiteralKind : uint8_t {
+#define MAGIC_IDENTIFIER(NAME, STRING, SYNTAX_KIND)                            \
+  BridgedMagicIdentifierLiteralKind##NAME,
+#include "swift/AST/MagicIdentifierKinds.def"
+  BridgedMagicIdentifierLiteralKindNone,
+};
+
+SWIFT_NAME("BridgedMagicIdentifierLiteralKind.init(from:)")
+BridgedMagicIdentifierLiteralKind
+BridgedMagicIdentifierLiteralKind_fromString(BridgedStringRef cStr);
+
+SWIFT_NAME("BridgedMagicIdentifierLiteralExpr.createParsed(_:kind:loc:)")
+BridgedMagicIdentifierLiteralExpr
+BridgedMagicIdentifierLiteralExpr_createParsed(
+    BridgedASTContext cContext, BridgedMagicIdentifierLiteralKind cKind,
+    BridgedSourceLoc cLoc);
+
 SWIFT_NAME("BridgedNilLiteralExpr.createParsed(_:nilKeywordLoc:)")
 BridgedNilLiteralExpr
 BridgedNilLiteralExpr_createParsed(BridgedASTContext cContext,

lib/AST/Bridging/ExprBridging.cpp

@@ -381,6 +381,36 @@ BridgedMacroExpansionExpr BridgedMacroExpansionExpr_createParsed(
                           : getFreestandingMacroRoles());
 }
 
+BridgedMagicIdentifierLiteralKind
+BridgedMagicIdentifierLiteralKind_fromString(BridgedStringRef cStr) {
+  StringRef str = cStr.unbridged();
+#define MAGIC_IDENTIFIER(NAME, STRING, SYNTAX_KIND)                            \
+  if (str == StringRef(STRING).drop_front())                                   \
+    return BridgedMagicIdentifierLiteralKind##NAME;
+#include "swift/AST/MagicIdentifierKinds.def"
+  return BridgedMagicIdentifierLiteralKindNone;
+}
+
+static std::optional<MagicIdentifierLiteralExpr::Kind>
+unbridge(BridgedMagicIdentifierLiteralKind cKind) {
+  switch (cKind) {
+#define MAGIC_IDENTIFIER(NAME, STRING, SYNTAX_KIND)                            \
+  case BridgedMagicIdentifierLiteralKind##NAME:                                \
+    return MagicIdentifierLiteralExpr::Kind::NAME;
+#include "swift/AST/MagicIdentifierKinds.def"
+  case BridgedMagicIdentifierLiteralKindNone:
+    return std::nullopt;
+  }
+}
+
+BridgedMagicIdentifierLiteralExpr
+BridgedMagicIdentifierLiteralExpr_createParsed(
+    BridgedASTContext cContext, BridgedMagicIdentifierLiteralKind cKind,
+    BridgedSourceLoc cLoc) {
+  return new (cContext.unbridged())
+      MagicIdentifierLiteralExpr(*unbridge(cKind), cLoc.unbridged());
+}
+
 BridgedNilLiteralExpr
 BridgedNilLiteralExpr_createParsed(BridgedASTContext cContext,
                                    BridgedSourceLoc cNilKeywordLoc) {

lib/ASTGen/Sources/ASTGen/Exprs.swift

@@ -71,7 +71,7 @@ extension ASTGenVisitor {
     case .keyPathExpr(let node):
       return self.generate(keyPathExpr: node)
     case .macroExpansionExpr(let node):
-      return self.generate(macroExpansionExpr: node).asExpr
+      return self.generate(macroExpansionExpr: node)
     case .memberAccessExpr(let node):
       return self.generate(memberAccessExpr: node)
     case .missingExpr:
@@ -797,9 +797,43 @@ extension ASTGenVisitor {
     )
   }
 
-  func generate(macroExpansionExpr node: MacroExpansionExprSyntax) -> BridgedMacroExpansionExpr {
+  func generateObjCSelectorExpr(macroExpansionExpr node: MacroExpansionExprSyntax) -> BridgedObjCSelectorExpr {
+    fatalError("unimplemented")
+  }
+
+  func generateObjCKeyPathExpr(macroExpansionExpr node: MacroExpansionExprSyntax) -> BridgedKeyPathExpr {
+    fatalError("unimplemented")
+  }
+
+  func generate(macroExpansionExpr node: MacroExpansionExprSyntax) -> BridgedExpr {
+    // '#file', '#line' etc.
+    let magicIdentifierKind = BridgedMagicIdentifierLiteralKind(from: node.macroName.rawText.bridged)
+    if magicIdentifierKind != .none {
+      guard node.lastToken(viewMode: .sourceAccurate) == node.macroName else {
+        // TODO: Diagnose
+        fatalError("magic identifier token with arguments")
+      }
+
+      return BridgedMagicIdentifierLiteralExpr.createParsed(
+        self.ctx,
+        kind: magicIdentifierKind,
+        loc: self.generateSourceLoc(node.macroName)
+      ).asExpr
+    }
+
+    // Other built-in pound expressions.
+    switch node.macroName.rawText {
+    case "selector":
+      return self.generateObjCSelectorExpr(macroExpansionExpr: node).asExpr
+    case "keyPath":  
+      return self.generateObjCKeyPathExpr(macroExpansionExpr: node).asExpr
+    default:
+      // Fallback to MacroExpansionExpr.
+      break
+    }
+
     let info = self.generate(freestandingMacroExpansion: node)
-    return .createParsed(
+    return BridgedMacroExpansionExpr.createParsed(
       self.declContext,
       poundLoc: info.poundLoc,
       macroNameRef: info.macroNameRef,
@@ -808,7 +842,7 @@ extension ASTGenVisitor {
       genericArgs: info.genericArgs,
       rightAngleLoc: info.rightAngleLoc,
       args: info.arguments
-    )
+    ).asExpr
   }
 
   func generate(memberAccessExpr node: MemberAccessExprSyntax, postfixIfConfigBaseExpr: BridgedExpr? = nil) -> BridgedExpr {

test/ASTGen/decls.swift

@@ -299,3 +299,7 @@ extension ValueStruct where 123 == N {}
 extension ValueStruct where N == -123 {}
 extension ValueStruct where -123 == N {}
 
+func testMagicIdentifier(file: String = #file, line: Int = #line) {
+    let _: String = file
+    let _: Int = line
+}