ASTGen: Translate precedence group declarations

Author: AnthonyLatsis

include/swift/AST/CASTBridging.h

@@ -488,6 +488,30 @@ void *OperatorDecl_create(
     BridgedIdentifier cPrecedenceGroupName,
     BridgedSourceLoc cPrecedenceGroupLoc);
 
+typedef enum ENUM_EXTENSIBILITY_ATTR(open) {
+  BridgedAssociativityNone,
+  BridgedAssociativityLeft,
+  BridgedAssociativityRight,
+} BridgedAssociativity;
+
+void *PrecedenceGroupDecl_create(
+    BridgedDeclContext cDeclContext,
+    BridgedSourceLoc cPrecedencegroupKeywordLoc,
+    BridgedIdentifier cName,
+    BridgedSourceLoc cNameLoc,
+    BridgedSourceLoc cLeftBraceLoc,
+    BridgedSourceLoc cAssociativityKeywordLoc,
+    BridgedSourceLoc cAssociativityValueLoc,
+    BridgedAssociativity cAssociativity,
+    BridgedSourceLoc cAssignmentKeywordLoc,
+    BridgedSourceLoc cAssignmentValueLoc,
+    _Bool isAssignment,
+    BridgedSourceLoc cHigherThanKeywordLoc,
+    BridgedArrayRef cHigherThanNames,
+    BridgedSourceLoc cLowerThanKeywordLoc,
+    BridgedArrayRef cLowerThanNames,
+    BridgedSourceLoc cRightBraceLoc);
+
 typedef enum ENUM_EXTENSIBILITY_ATTR(open) {
   BridgedImportKindModule,
   BridgedImportKindType,

lib/AST/CASTBridging.cpp

@@ -875,6 +875,63 @@ void *OperatorDecl_create(
   return static_cast<Decl *>(decl);
 }
 
+void *PrecedenceGroupDecl_create(
+    BridgedDeclContext cDeclContext,
+    BridgedSourceLoc cPrecedencegroupKeywordLoc,
+    BridgedIdentifier cName,
+    BridgedSourceLoc cNameLoc,
+    BridgedSourceLoc cLeftBraceLoc,
+    BridgedSourceLoc cAssociativityKeywordLoc,
+    BridgedSourceLoc cAssociativityValueLoc,
+    BridgedAssociativity cAssociativity,
+    BridgedSourceLoc cAssignmentKeywordLoc,
+    BridgedSourceLoc cAssignmentValueLoc,
+    bool isAssignment,
+    BridgedSourceLoc cHigherThanKeywordLoc,
+    BridgedArrayRef cHigherThanNames,
+    BridgedSourceLoc cLowerThanKeywordLoc,
+    BridgedArrayRef cLowerThanNames,
+    BridgedSourceLoc cRightBraceLoc) {
+
+  SmallVector<PrecedenceGroupDecl::Relation, 2> higherThanNames;
+  for (auto &pair :
+       convertArrayRef<BridgedIdentifierAndSourceLoc>(cHigherThanNames)) {
+    higherThanNames.push_back(
+        {convertSourceLoc(pair.nameLoc),
+         convertIdentifier(pair.name),
+         nullptr});
+  }
+
+  SmallVector<PrecedenceGroupDecl::Relation, 2> lowerThanNames;
+  for (auto &pair :
+       convertArrayRef<BridgedIdentifierAndSourceLoc>(cLowerThanNames)) {
+    lowerThanNames.push_back(
+        {convertSourceLoc(pair.nameLoc),
+         convertIdentifier(pair.name),
+         nullptr});
+  }
+
+  auto *decl = PrecedenceGroupDecl::create(
+      convertDeclContext(cDeclContext),
+      convertSourceLoc(cPrecedencegroupKeywordLoc),
+      convertSourceLoc(cNameLoc),
+      convertIdentifier(cName),
+      convertSourceLoc(cLeftBraceLoc),
+      convertSourceLoc(cAssociativityKeywordLoc),
+      convertSourceLoc(cAssociativityValueLoc),
+      static_cast<Associativity>(cAssociativity),
+      convertSourceLoc(cAssignmentKeywordLoc),
+      convertSourceLoc(cAssignmentValueLoc),
+      isAssignment,
+      convertSourceLoc(cHigherThanKeywordLoc),
+      higherThanNames,
+      convertSourceLoc(cLowerThanKeywordLoc),
+      lowerThanNames,
+      convertSourceLoc(cRightBraceLoc));
+
+  return static_cast<Decl *>(decl);
+}
+
 void *ImportDecl_create(
     BridgedASTContext cContext,
     BridgedDeclContext cDeclContext,

lib/ASTGen/Sources/ASTGen/Decls.swift

@@ -378,6 +378,86 @@ extension ASTGenVisitor {
   }
 }
 
+extension BridgedAssociativity {
+  fileprivate init(tokenKind: TokenKind) {
+    switch tokenKind {
+    case .keyword(.none): self = .none
+    case .keyword(.left): self = .left
+    case .keyword(.right): self = .right
+    default: fatalError("Unknown precedence group associativity value")
+    }
+  }
+}
+
+extension ASTGenVisitor {
+  func visit(_ node: PrecedenceGroupDeclSyntax) -> ASTNode {
+    let (name, nameLoc) = self.bridgedIdentifierAndSourceLoc(for: node.identifier)
+
+    struct PrecedenceGroupBody {
+      var associativity: PrecedenceGroupAssociativitySyntax? = nil
+      var assignment: PrecedenceGroupAssignmentSyntax? = nil
+      var higherThanRelation: PrecedenceGroupRelationSyntax? = nil
+      var lowerThanRelation: PrecedenceGroupRelationSyntax? = nil
+    }
+
+    let body = node.groupAttributes.reduce(into: PrecedenceGroupBody()) { partialResult, element in
+      switch element {
+      case .precedenceGroupRelation(let node):
+        switch node.higherThanOrLowerThan.tokenKind {
+        case .keyword(.higherThan): partialResult.higherThanRelation = node
+        case .keyword(.lowerThan): partialResult.lowerThanRelation = node
+        default: fatalError("Unknown precedence group relation attribute")
+        }
+      case .precedenceGroupAssignment(let node):
+        partialResult.assignment = node
+      case .precedenceGroupAssociativity(let node):
+        partialResult.associativity = node
+      }
+    }
+
+    let associativityValue = body.associativity.map { BridgedAssociativity(tokenKind: $0.value.tokenKind) } ?? .none
+    let assignmentValue =
+      body.assignment.map {
+        switch $0.flag.tokenKind {
+        case .keyword(.true): return true
+        case .keyword(.false): return false
+        default: fatalError("Unknown precedence group assignment value")
+        }
+      } ?? false
+
+    return .decl(
+      (body.higherThanRelation?.otherNames).map {
+        let (name, nameLoc) = self.bridgedIdentifierAndSourceLoc(for: $0.name)
+        return BridgedIdentifierAndSourceLoc(name: name, nameLoc: nameLoc)
+      } withBridgedArrayRef: { higherThanNames in
+        (body.lowerThanRelation?.otherNames).map {
+          let (name, nameLoc) = self.bridgedIdentifierAndSourceLoc(for: $0.name)
+          return BridgedIdentifierAndSourceLoc(name: name, nameLoc: nameLoc)
+        } withBridgedArrayRef: { lowerThanNames in
+          PrecedenceGroupDecl_create(
+            self.declContext,
+            self.bridgedSourceLoc(for: node.precedencegroupKeyword),
+            name,
+            nameLoc,
+            self.bridgedSourceLoc(for: node.leftBrace),
+            self.bridgedSourceLoc(for: body.associativity?.associativityKeyword),
+            self.bridgedSourceLoc(for: body.associativity?.value),
+            associativityValue,
+            self.bridgedSourceLoc(for: body.assignment?.assignmentKeyword),
+            self.bridgedSourceLoc(for: body.assignment?.flag),
+            assignmentValue,
+            self.bridgedSourceLoc(for: body.higherThanRelation?.higherThanOrLowerThan),
+            higherThanNames,
+            self.bridgedSourceLoc(for: body.lowerThanRelation?.higherThanOrLowerThan),
+            lowerThanNames,
+            self.bridgedSourceLoc(for: node.rightBrace)
+          )
+        }
+      }
+    )
+  }
+}
+
 // MARK: - ImportDecl
 
 extension BridgedImportKind {

test/ASTGen/verify-parse.swift

@@ -191,3 +191,14 @@ operator
 
 postfix
 operator ⎩^-^⎩
+
+
+precedencegroup Precedence1 {
+}
+
+precedencegroup Precedence2 {
+  lowerThan: BitwiseShiftPrecedence, MultiplicationPrecedence
+  higherThan: Precedence1, AdditionPrecedence
+  associativity: left
+  assignment: true
+}