Merge pull request #1242 from elfredpagan/elfred_pagan_throw_fromDatatypeValue

make fromDatatypeValue throw

Author: nathanfallet

Sources/SQLite/Core/Value.swift

@@ -39,7 +39,7 @@ public protocol Value: Expressible { // extensions cannot have inheritance claus
 
     static var declaredDatatype: String { get }
 
-    static func fromDatatypeValue(_ datatypeValue: Datatype) -> ValueType
+    static func fromDatatypeValue(_ datatypeValue: Datatype) throws -> ValueType
 
     var datatypeValue: Datatype { get }
 

Sources/SQLite/Helpers.swift

@@ -121,9 +121,9 @@ func transcode(_ literal: Binding?) -> String {
     }
 }
 
-// swiftlint:disable force_cast
+// swiftlint:disable force_cast force_try
 func value<A: Value>(_ binding: Binding) -> A {
-    A.fromDatatypeValue(binding as! A.Datatype) as! A
+    try! A.fromDatatypeValue(binding as! A.Datatype) as! A
 }
 
 func value<A: Value>(_ binding: Binding?) -> A {

Sources/SQLite/Typed/Query.swift

@@ -1097,7 +1097,7 @@ extension Connection {
     public func scalar<V: Value>(_ query: ScalarQuery<V?>) throws -> V.ValueType? {
         let expression = query.expression
         guard let value = try scalar(expression.template, expression.bindings) as? V.Datatype else { return nil }
-        return V.fromDatatypeValue(value)
+        return try V.fromDatatypeValue(value)
     }
 
     public func scalar<V: Value>(_ query: Select<V>) throws -> V {
@@ -1108,7 +1108,7 @@ extension Connection {
     public func scalar<V: Value>(_ query: Select<V?>) throws -> V.ValueType? {
         let expression = query.expression
         guard let value = try scalar(expression.template, expression.bindings) as? V.Datatype else { return nil }
-        return V.fromDatatypeValue(value)
+        return try V.fromDatatypeValue(value)
     }
 
     public func pluck(_ query: QueryType) throws -> Row? {
@@ -1200,9 +1200,9 @@ public struct Row {
     }
 
     public func get<V: Value>(_ column: Expression<V?>) throws -> V? {
-        func valueAtIndex(_ idx: Int) -> V? {
+        func valueAtIndex(_ idx: Int) throws -> V? {
             guard let value = values[idx] as? V.Datatype else { return nil }
-            return V.fromDatatypeValue(value) as? V
+            return try V.fromDatatypeValue(value) as? V
         }
 
         guard let idx = columnNames[column.template] else {
@@ -1224,10 +1224,10 @@ public struct Row {
                     similar: columnNames.keys.filter(similar).sorted()
                 )
             }
-            return valueAtIndex(columnNames[firstIndex].value)
+            return try valueAtIndex(columnNames[firstIndex].value)
         }
 
-        return valueAtIndex(idx)
+        return try valueAtIndex(idx)
     }
 
     public subscript<T: Value>(column: Expression<T>) -> T {

Tests/SQLiteTests/Typed/RowTests.swift

@@ -85,4 +85,34 @@ class RowTests: XCTestCase {
             }
         }
     }
+
+    public func test_get_datatype_throws() {
+        // swiftlint:disable nesting
+        struct MyType: Value {
+            enum MyError: Error {
+                case failed
+            }
+
+            public static var declaredDatatype: String {
+                Blob.declaredDatatype
+            }
+
+            public static func fromDatatypeValue(_ dataValue: Blob) throws -> Data {
+                throw MyError.failed
+            }
+
+            public var datatypeValue: Blob {
+                return Blob(bytes: [])
+            }
+        }
+
+        let row = Row(["\"foo\"": 0], [Blob(bytes: [])])
+        XCTAssertThrowsError(try row.get(Expression<MyType>("foo"))) { error in
+            if case MyType.MyError.failed = error {
+                XCTAssertTrue(true)
+            } else {
+                XCTFail("unexpected error: \(error)")
+            }
+        }
+    }
 }