added delegate func for empty insert stats. test

Author: Kyle Jessup

Package.swift

@@ -31,7 +31,7 @@ let package = Package(
 		.library(name: "PerfectMySQL", targets: ["PerfectMySQL"])
 	],
 	dependencies: [
-		.package(url: "https://github.com/PerfectlySoft/Perfect-CRUD.git", from: "1.2.0"),
+		.package(url: "https://github.com/PerfectlySoft/Perfect-CRUD.git", from: "1.2.2"),
 		.package(url: "https://github.com/PerfectlySoft/\(clientPackage).git", from: "2.0.0"),
 		],
 	targets: [

Sources/PerfectMySQL/MySQLCRUD.swift

@@ -187,6 +187,10 @@ class MySQLGenDelegate: SQLGenDelegate {
 		database = db
 	}
 
+	func getEmptyInsertSnippet() -> String {
+		return "() VALUES ()"
+	}
+	
 	func getBinding(for expr: Expression) throws -> String {
 		bindings.append(("?", expr))
 		return "?"

Tests/PerfectMySQLTests/PerfectMySQLTests.swift

@@ -1739,6 +1739,32 @@ class PerfectMySQLTests: XCTestCase {
 		}
 	}
 
+	func testEmptyInsert() {
+		do {
+			let db = try getTestDB()
+			struct ReturningItem: Codable, Equatable {
+				let id: Int?
+				var def: Int?
+				init(id: Int, def: Int? = nil) {
+					self.id = id
+					self.def = def
+				}
+			}
+			try db.sql("DROP TABLE IF EXISTS \(ReturningItem.CRUDTableName)")
+			try db.sql("CREATE TABLE \(ReturningItem.CRUDTableName) (id INT PRIMARY KEY AUTO_INCREMENT, def INT DEFAULT 42)")
+			let table = db.table(ReturningItem.self)
+			
+			let id = try table
+				.insert(ReturningItem(id: 0, def: 0),
+						ignoreKeys: \ReturningItem.id, \ReturningItem.def)
+				.lastInsertId()
+			XCTAssertEqual(id, 1)
+			
+		} catch {
+			XCTFail("\(error)")
+		}
+	}
+	
 	static var allTests = [
 		("testConnect", testConnect),
 		("testListDbs1", testListDbs1),
@@ -1788,7 +1814,8 @@ class PerfectMySQLTests: XCTestCase {
 		("testAllPrimTypes2", testAllPrimTypes2),
 		("testBespokeSQL", testBespokeSQL),
 		("testURL", testURL),
-		("testLastInsertId", testLastInsertId)
+		("testLastInsertId", testLastInsertId),
+		("testEmptyInsert", testEmptyInsert)
 	]
 }