| // Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| // Verify semantics of the ??= operator, including order of operations, by |
| // keeping track of the operations performed. |
| |
| import "package:expect/expect.dart"; |
| import "assignment_helper.dart" as h; |
| |
| bad() { |
| Expect.fail('Should not be executed'); |
| } |
| |
| var xGetValue = null; |
| |
| get x { |
| h.operations.add('x'); |
| var tmp = xGetValue; |
| xGetValue = null; |
| return tmp; |
| } |
| |
| void set x(value) { |
| h.operations.add('x=$value'); |
| } |
| |
| var yGetValue = null; |
| |
| get y { |
| h.operations.add('y'); |
| var tmp = yGetValue; |
| yGetValue = null; |
| return tmp; |
| } |
| |
| void set y(value) { |
| h.operations.add('y=$value'); |
| } |
| |
| var zGetValue = null; |
| |
| get z { |
| h.operations.add('z'); |
| var tmp = zGetValue; |
| zGetValue = null; |
| return tmp; |
| } |
| |
| void set z(value) { |
| h.operations.add('z=$value'); |
| } |
| |
| var fValue = null; |
| |
| f() { |
| h.operations.add('f()'); |
| var tmp = fValue; |
| fValue = null; |
| return tmp; |
| } |
| |
| void check(expectedValue, f(), expectedOperations) { |
| Expect.equals(expectedValue, f()); |
| Expect.listEquals(expectedOperations, h.operations); |
| h.operations = []; |
| } |
| |
| class C { |
| final String s; |
| |
| C(this.s); |
| |
| @override |
| String toString() => s; |
| |
| static var xGetValue = null; |
| |
| static get x { |
| h.operations.add('C.x'); |
| var tmp = xGetValue; |
| xGetValue = null; |
| return tmp; |
| } |
| |
| static void set x(value) { |
| h.operations.add('C.x=$value'); |
| } |
| |
| var vGetValue = null; |
| |
| get v { |
| h.operations.add('$s.v'); |
| var tmp = vGetValue; |
| vGetValue = null; |
| return tmp; |
| } |
| |
| void set v(value) { |
| h.operations.add('$s.v=$value'); |
| } |
| |
| var indexGetValue = null; |
| |
| operator [](index) { |
| h.operations.add('$s[$index]'); |
| var tmp = indexGetValue; |
| indexGetValue = null; |
| return tmp; |
| } |
| |
| void operator []=(index, value) { |
| h.operations.add('$s[$index]=$value'); |
| } |
| |
| final finalOne = 1; |
| final finalNull = null; |
| |
| void instanceTest() { |
| // v ??= e is equivalent to ((x) => x == null ? v = e : x)(v) |
| vGetValue = 1; |
| check(1, () => v ??= bad(), ['$s.v']); |
| yGetValue = 1; |
| check(1, () => v ??= y, ['$s.v', 'y', '$s.v=1']); |
| finalOne ??= null; |
| // ^^^^^^^^ |
| // [analyzer] COMPILE_TIME_ERROR.ASSIGNMENT_TO_FINAL |
| // [cfe] Operand of null-aware operation '??=' has type 'int' which excludes null. |
| // ^ |
| // [cfe] The setter 'finalOne' isn't defined for the class 'C'. |
| // ^^^^ |
| // [analyzer] STATIC_WARNING.DEAD_NULL_AWARE_EXPRESSION |
| yGetValue = 1; |
| } |
| } |
| |
| class D extends C { |
| D(String s) : super(s); |
| |
| get v => bad(); |
| |
| void set v(value) { |
| bad(); |
| } |
| |
| void derivedInstanceTest() { |
| // super.v ??= e is equivalent to |
| // ((x) => x == null ? super.v = e : x)(super.v) |
| vGetValue = 1; |
| check(1, () => super.v ??= bad(), ['$s.v']); |
| yGetValue = 1; |
| check(1, () => super.v ??= y, ['$s.v', 'y', '$s.v=1']); |
| } |
| } |
| |
| main() { |
| // Make sure the "none" test fails if "??=" is not implemented. This makes |
| // status files easier to maintain. |
| var _; |
| _ ??= null; |
| |
| new C('c').instanceTest(); |
| new D('d').derivedInstanceTest(); |
| |
| // v ??= e is equivalent to ((x) => x == null ? v = e : x)(v) |
| xGetValue = 1; |
| check(1, () => x ??= bad(), ['x']); |
| yGetValue = 1; |
| check(1, () => x ??= y, ['x', 'y', 'x=1']); |
| h.xGetValue = 1; |
| check(1, () => h.x ??= bad(), ['h.x']); |
| yGetValue = 1; |
| check(1, () => h.x ??= y, ['h.x', 'y', 'h.x=1']); |
| { |
| var l = 1; |
| check(1, () => l ??= bad(), []); |
| // ^ |
| // [cfe] Operand of null-aware operation '??=' has type 'int' which excludes null. |
| // ^^^^^ |
| // [analyzer] STATIC_WARNING.DEAD_NULL_AWARE_EXPRESSION |
| } |
| { |
| var l; |
| yGetValue = 1; |
| check(1, () => l ??= y, ['y']); |
| Expect.equals(1, l); |
| } |
| { |
| final l = 1; |
| l ??= null; |
| // ^ |
| // [analyzer] COMPILE_TIME_ERROR.ASSIGNMENT_TO_FINAL_LOCAL |
| // [cfe] Can't assign to the final variable 'l'. |
| // ^ |
| // [cfe] Operand of null-aware operation '??=' has type 'int' which excludes null. |
| // ^^^^ |
| // [analyzer] COMPILE_TIME_ERROR.INVALID_ASSIGNMENT |
| // ^^^^ |
| // [analyzer] STATIC_WARNING.DEAD_NULL_AWARE_EXPRESSION |
| } |
| C ??= null; |
| //^ |
| // [analyzer] COMPILE_TIME_ERROR.ASSIGNMENT_TO_TYPE |
| // [cfe] Can't assign to a type literal. |
| //^ |
| // [cfe] Operand of null-aware operation '??=' has type 'Type' which excludes null. |
| h ??= null; |
| //^ |
| // [analyzer] COMPILE_TIME_ERROR.PREFIX_IDENTIFIER_NOT_FOLLOWED_BY_DOT |
| // [cfe] A prefix can't be used as an expression. |
| h[0] ??= null; |
| //^ |
| // [analyzer] COMPILE_TIME_ERROR.PREFIX_IDENTIFIER_NOT_FOLLOWED_BY_DOT |
| // [cfe] A prefix can't be used as an expression. |
| |
| // C.v ??= e is equivalent to ((x) => x == null ? C.v = e : x)(C.v) |
| C.xGetValue = 1; |
| check(1, () => C.x ??= bad(), ['C.x']); |
| yGetValue = 1; |
| check(1, () => C.x ??= y, ['C.x', 'y', 'C.x=1']); |
| h.C.xGetValue = 1; |
| check(1, () => h.C.x ??= bad(), ['h.C.x']); |
| yGetValue = 1; |
| check(1, () => h.C.x ??= y, ['h.C.x', 'y', 'h.C.x=1']); |
| |
| // e1.v ??= e2 is equivalent to |
| // ((x) => ((y) => y == null ? x.v = e2 : y)(x.v))(e1) |
| xGetValue = new C('x'); |
| xGetValue.vGetValue = 1; |
| check(1, () => x.v ??= bad(), ['x', 'x.v']); |
| xGetValue = new C('x'); |
| yGetValue = 1; |
| check(1, () => x.v ??= y, ['x', 'x.v', 'y', 'x.v=1']); |
| fValue = new C('f()'); |
| fValue.vGetValue = 1; |
| check(1, () => f().v ??= bad(), ['f()', 'f().v']); |
| fValue = new C('f()'); |
| yGetValue = 1; |
| check(1, () => f().v ??= y, ['f()', 'f().v', 'y', 'f().v=1']); |
| |
| // e1[e2] ??= e3 is equivalent to |
| // ((a, i) => ((x) => x == null ? a[i] = e3 : x)(a[i]))(e1, e2) |
| xGetValue = new C('x'); |
| yGetValue = 1; |
| xGetValue.indexGetValue = 2; |
| check(2, () => x[y] ??= bad(), ['x', 'y', 'x[1]']); |
| xGetValue = new C('x'); |
| yGetValue = 1; |
| zGetValue = 2; |
| check(2, () => x[y] ??= z, ['x', 'y', 'x[1]', 'z', 'x[1]=2']); |
| |
| // e1?.v ??= e2 is equivalent to ((x) => x == null ? null : x.v ??= e2)(e1). |
| check(null, () => x?.v ??= bad(), ['x']); |
| xGetValue = new C('x'); |
| xGetValue.vGetValue = 1; |
| check(1, () => x?.v ??= bad(), ['x', 'x.v']); |
| xGetValue = new C('x'); |
| yGetValue = 1; |
| check(1, () => x?.v ??= y, ['x', 'x.v', 'y', 'x.v=1']); |
| |
| // C?.v ??= e2 is equivalent to C.v ??= e2. |
| C.xGetValue = 1; |
| check(1, () => C?.x ??= bad(), ['C.x']); |
| // ^ |
| // [cfe] The class 'C' cannot be null. |
| h.C.xgetValue = 1; |
| // ^^^^^^^^^ |
| // [analyzer] COMPILE_TIME_ERROR.UNDEFINED_SETTER |
| // [cfe] Setter not found: 'xgetValue'. |
| check(1, () => h.c?.x ??= bad(), ['h.C.x']); |
| // ^ |
| // [analyzer] COMPILE_TIME_ERROR.UNDEFINED_PREFIXED_NAME |
| // [cfe] Getter not found: 'c'. |
| yGetValue = 1; |
| check(1, () => C?.x ??= y, ['C.x', 'y', 'C.x=1']); |
| // ^ |
| // [cfe] The class 'C' cannot be null. |
| yGetValue = 1; |
| check(1, () => h.C?.x ??= y, ['h.C.x', 'y', 'h.C.x=1']); |
| // ^ |
| // [cfe] The class 'C' cannot be null. |
| } |