Class initializer generation

Sources/GRDBMacros/Macros.swift

@@ -13,6 +13,10 @@ import GRDB
   conformances: FetchableRecord, PersistableRecord,
   names: named(init(row:)), named(encode(to:)), named(Columns), named(databaseSelection)
 )
+@attached(
+  member,
+  names: named(init(row:))
+)
 public macro DatabaseRecord() = #externalMacro(module: "GRDBMacrosPlugin", type: "DatabaseRecordMacro")
 
 @attached(peer)

Sources/GRDBMacrosPlugin/DatabaseRecordMacro.swift

@@ -58,6 +58,7 @@ extension DatabaseRecordMacro: ExtensionMacro {
     }
 
     let isPublic = declaration.modifiers.map(\.name.tokenKind).contains(.keyword(.public))
+    let isClass = declaration.is(ClassDeclSyntax.self)
 
     let access = if isPublic {
       TokenSyntax(.keyword(.public), trailingTrivia: [.spaces(1)], presence: .present)
@@ -72,6 +73,7 @@ extension DatabaseRecordMacro: ExtensionMacro {
 
     let needsExtImpl: [ExtensionWithBody] = [
       .init(name: fetchableType) {
+        isClass ? "" :
         """
         \(raw: access)init(row: \(raw: qualified("Row"))) {
         \(raw: args.map(\.fetchableDecl.trimmedDescription).joined(separator: "\n"))
@@ -126,6 +128,50 @@ extension DatabaseRecordMacro: ExtensionMacro {
   }
 }
 
+extension DatabaseRecordMacro: MemberMacro {
+  static func expansion(
+    of node: AttributeSyntax,
+    providingMembersOf declaration: some DeclGroupSyntax,
+    conformingTo protocols: [TypeSyntax],
+    in context: some MacroExpansionContext
+  ) throws -> [DeclSyntax] {
+    if declaration.is(StructDeclSyntax.self) {
+      return []
+    }
+    guard let declaration = declaration.as(ClassDeclSyntax.self) else {
+      throw Error.onlyClassOrStructs
+    }
+
+    let isPublic = declaration.modifiers.map(\.name.tokenKind).contains(.keyword(.public))
+
+    let access = if isPublic {
+      TokenSyntax(.keyword(.public), trailingTrivia: [.spaces(1)], presence: .present)
+    } else {
+      TokenSyntax(.stringSegment(""), presence: .missing)
+    }
+
+    let inherited = declaration.inheritanceClause?.inheritedTypes ?? []
+
+    if inherited.map(\.type).contains(where: {
+      $0.trimmedDescription == fetchableType ||
+      $0.trimmedDescription == qualified(DeclSyntax(stringLiteral: fetchableType)).trimmedDescription
+    }) {
+      return []
+    }
+
+    let args: [MemberColumn] = declaration.memberBlock.members
+      .compactMap(MemberColumn.init)
+
+    return [
+        """
+        \(raw: access)required init(row: \(raw: qualified("Row"))) {
+        \(raw: args.map(\.fetchableDecl.trimmedDescription).joined(separator: "\n"))
+        }
+        """
+    ]
+  }
+}
+
 // MARK: - MemberColumn + init & properties
 
 extension DatabaseRecordMacro.MemberColumn {

Tests/GRDBMacrosTests/GRDBMacrosTests.swift

@@ -135,4 +135,52 @@ final class GRDBMacrosTests: XCTestCase {
       """
     }
   }
+
+  func testMacroForClass() throws {
+    assertMacro {
+      """
+      @DatabaseRecord
+      class Author {
+        var id: Int64?
+        var countryCode: String?
+      }
+      """
+    } expansion: {
+      """
+      class Author {
+        var id: Int64?
+        var countryCode: String?
+
+        required init(row: GRDB.Row) {
+           self.id = row[Columns.id]
+           self.countryCode = row[Columns.countryCode]
+        }
+      }
+
+      extension Author: GRDB.FetchableRecord {
+      }
+
+      extension Author: GRDB.PersistableRecord {
+        func encode(to container: inout GRDB.PersistenceContainer) throws {
+           container[Columns.id] = id
+           container[Columns.countryCode] = countryCode
+        }
+      }
+
+      extension Author {
+        enum Columns {
+          static let id = GRDB.Column("id")
+          static let countryCode = GRDB.Column("countryCode")
+        }
+      }
+
+      extension Author {
+        static let databaseSelection: [any GRDB.SQLSelectable] = [
+          Columns.id,
+          Columns.countryCode
+        ]
+      }
+      """
+    }
+  }
 }