add swiftUI code

2025-01-22 14:09:10 +08:00
parent 68e7b7347c
commit 8a99853829
2531 changed files with 486215 additions and 0 deletions
@@ -0,0 +1,58 @@
+import XCTest
+import GRDB
+
+struct DatabaseTimestamp: DatabaseValueConvertible {
+    
+    // Date conversion
+    //
+    // We consistently use the Swift nil to represent the database NULL: the
+    // date property is a non-optional Date, and the Date initializer is
+    // failable:
+    
+    /// The represented date
+    let date: Date
+    
+    /// Creates a DatabaseTimestamp from an Date.
+    /// The result is nil if and only if *date* is nil.
+    init?(_ date: Date?) {
+        guard let date else {
+            return nil
+        }
+        self.date = date
+    }
+    
+    
+    // DatabaseValueConvertible adoption
+    
+    /// Returns a value that can be stored in the database.
+    var databaseValue: DatabaseValue {
+        date.timeIntervalSince1970.databaseValue
+    }
+    
+    /// Returns a value initialized from *dbValue*, if possible.
+    static func fromDatabaseValue(_ dbValue: DatabaseValue) -> DatabaseTimestamp? {
+        // Double itself adopts DatabaseValueConvertible. So let's avoid
+        // handling the raw DatabaseValue, and use built-in Double conversion:
+        guard let timeInterval = Double.fromDatabaseValue(dbValue) else {
+            // No Double, no Date!
+            return nil
+        }
+        return DatabaseTimestamp(Date(timeIntervalSince1970: timeInterval))
+    }
+}
+
+
+class DatabaseTimestampTests: GRDBTestCase {
+
+    func testDatabaseTimestamp() throws {
+        let dbQueue = try makeDatabaseQueue()
+        try dbQueue.inDatabase { db in
+            try db.execute(sql: "CREATE TABLE dates (date DATETIME)")
+            let storedDate = Date()
+            try db.execute(sql: "INSERT INTO dates (date) VALUES (?)", arguments: [DatabaseTimestamp(storedDate)])
+            let fetchedDate = try DatabaseTimestamp.fetchOne(db, sql: "SELECT date FROM dates")!.date
+            let delta = storedDate.timeIntervalSince(fetchedDate)
+            XCTAssertTrue(abs(delta) < 0.1)
+        }
+    }
+}