#1401. [Patterns] Logical-or tests added (#1520)

Authored by @sgrekhov.

Add logical-or tests. Using a log to detect execution of getters during a matching step.

LanguageFeatures/Patterns/logical_or_A01_t01.dart

@@ -0,0 +1,48 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion logicalOrPattern ::= ( logicalOrPattern '|' )? logicalAndPattern
+///
+/// A pair of patterns separated by | matches if either of the branches match
+///
+/// A logical-or pattern may match even if one of its branches does not. That
+/// means that any variables in the non-matching branch would not be
+/// initialized. To avoid problems stemming from that, the following
+/// restrictions apply:
+///
+/// The two branches must define the same set of variables.
+///
+/// If the left branch matches, the right branch is not evaluated. This
+/// determines which value the variable gets if both branches would have
+/// matched. In that case, it will always be the value from the left branch.
+///
+/// @description Checks logical-or pattern in a switch expression
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=patterns
+
+import "../../Utils/expect.dart";
+
+enum Color {
+  white,
+  red,
+  yellow,
+  blue,
+  black;
+}
+
+bool isPrimary(Color color) {
+  return switch (color) {
+    case Color.red | Color.yellow | Color.blue => true;
+    default => false;
+  };
+}
+
+main() {
+  Expect.isFalse(isPrimary(Color.black));
+  Expect.isFalse(isPrimary(Color.white));
+  Expect.isTrue(isPrimary(Color.red));
+  Expect.isTrue(isPrimary(Color.yellow));
+  Expect.isTrue(isPrimary(Color.blue));
+}

LanguageFeatures/Patterns/logical_or_A01_t02.dart

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+// Copyright (c) 2022, 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.
+
+/// @assertion logicalOrPattern ::= ( logicalOrPattern '|' )? logicalAndPattern
+///
+/// A pair of patterns separated by | matches if either of the branches match
+///
+/// A logical-or pattern may match even if one of its branches does not. That
+/// means that any variables in the non-matching branch would not be
+/// initialized. To avoid problems stemming from that, the following
+/// restrictions apply:
+///
+/// The two branches must define the same set of variables.
+///
+/// If the left branch matches, the right branch is not evaluated. This
+/// determines which value the variable gets if both branches would have
+/// matched. In that case, it will always be the value from the left branch.
+///
+/// @description Checks logical-or subpattern in a switch expression
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=patterns
+
+import "../../Utils/expect.dart";
+
+bool matches(List list) => switch (list) {
+  case [1 | 2, 3] => true;
+  default => false;
+};
+
+main() {
+  Expect.isFalse(matches([0, 3]));
+  Expect.isFalse(matches([2, 2]));
+  Expect.isFalse(matches([2, 3, 4]));
+  Expect.isFalse(matches([2, "3"]));
+  Expect.isFalse(matches(["1", 3]));
+  Expect.isTrue(matches([1, 3]));
+  Expect.isTrue(matches([2, 3]));
+}

LanguageFeatures/Patterns/logical_or_A02_t01.dart

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+// Copyright (c) 2022, 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.
+
+/// @assertion logicalOrPattern ::= ( logicalOrPattern '|' )? logicalAndPattern
+///
+/// A pair of patterns separated by | matches if either of the branches match
+///
+/// A logical-or pattern may match even if one of its branches does not. That
+/// means that any variables in the non-matching branch would not be
+/// initialized. To avoid problems stemming from that, the following
+/// restrictions apply:
+///
+/// The two branches must define the same set of variables.
+///
+/// If the left branch matches, the right branch is not evaluated. This
+/// determines which value the variable gets if both branches would have
+/// matched. In that case, it will always be the value from the left branch.
+///
+/// @description Checks logical-or pattern in a switch statement
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=patterns
+
+import "patterns_lib.dart";
+import "../../Utils/expect.dart";
+
+void test(Shape shape, double expectedArea, Type expectedType, bool match) {
+  switch (shape) {
+    case Square(area: var s) | Circle(area: var s):
+      Expect.equals(s, expectedArea);
+      Expect.equals(expectedType, shape.runtimeType);
+      Expect.isTrue(match);
+      break;
+    default:
+      Expect.equals(s, expectedArea);
+      Expect.equals(expectedType, shape.runtimeType);
+      Expect.isFalse(match);
+  }
+}
+
+main() {
+  test(Circle(1), 3.14, Circle, true);
+  test(Square(2), 4, Square, true);
+  test(Rectangle(2, 1), 2, Rectangle, false);
+}

LanguageFeatures/Patterns/logical_or_A02_t02.dart

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+// Copyright (c) 2022, 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.
+
+/// @assertion logicalOrPattern ::= ( logicalOrPattern '|' )? logicalAndPattern
+///
+/// A pair of patterns separated by | matches if either of the branches match
+///
+/// A logical-or pattern may match even if one of its branches does not. That
+/// means that any variables in the non-matching branch would not be
+/// initialized. To avoid problems stemming from that, the following
+/// restrictions apply:
+///
+/// The two branches must define the same set of variables.
+///
+/// If the left branch matches, the right branch is not evaluated. This
+/// determines which value the variable gets if both branches would have
+/// matched. In that case, it will always be the value from the left branch.
+///
+/// @description Checks logical-or subpattern in a switch statement
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=patterns
+
+import "../../Utils/expect.dart";
+
+bool matches(List list) {
+  bool result = false;
+  switch (list) {
+    case [1 | 2, 3]:
+      result = true;
+    default:
+  };
+  return result;
+}
+
+main() {
+  Expect.isFalse(matches([0, 3]));
+  Expect.isFalse(matches([2, 2]));
+  Expect.isFalse(matches([2, 3, 4]));
+  Expect.isFalse(matches([2, "3"]));
+  Expect.isFalse(matches(["1", 3]));
+  Expect.isTrue(matches([1, 3]));
+  Expect.isTrue(matches([2, 3]));
+}

LanguageFeatures/Patterns/logical_or_A03_t01.dart

@@ -0,0 +1,46 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion logicalOrPattern ::= ( logicalOrPattern '|' )? logicalAndPattern
+///
+/// A pair of patterns separated by | matches if either of the branches match
+///
+/// A logical-or pattern may match even if one of its branches does not. That
+/// means that any variables in the non-matching branch would not be
+/// initialized. To avoid problems stemming from that, the following
+/// restrictions apply:
+///
+/// The two branches must define the same set of variables.
+///
+/// If the left branch matches, the right branch is not evaluated. This
+/// determines which value the variable gets if both branches would have
+/// matched. In that case, it will always be the value from the left branch.
+///
+/// @description Checks that it is a compile-time error if two branches of
+/// logical-or pattern define different sets of variables
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=patterns
+
+import "patterns_lib.dart";
+
+main() {
+  Shape shape = Circle(1);
+  switch (shape) {
+    case Square(area: var s1) | Circle(area: var s2):
+//                                               ^^
+// [analyzer] unspecified
+// [cfe] unspecified
+      print("Square or Circle");
+      break;
+    case Rectangle(x: var x, y: var width) | Rectangle(:var x, :var y):
+//                                                                  ^
+// [analyzer] unspecified
+// [cfe] unspecified
+      print("Rectangle");
+      break;
+    default:
+      print("Other");
+  }
+}

LanguageFeatures/Patterns/logical_or_A04_t01.dart

@@ -0,0 +1,56 @@
+// Copyright (c) 2022, 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.
+
+/// @assertion logicalOrPattern ::= ( logicalOrPattern '|' )? logicalAndPattern
+///
+/// A pair of patterns separated by | matches if either of the branches match
+///
+/// A logical-or pattern may match even if one of its branches does not. That
+/// means that any variables in the non-matching branch would not be
+/// initialized. To avoid problems stemming from that, the following
+/// restrictions apply:
+///
+/// The two branches must define the same set of variables.
+///
+/// If the left branch matches, the right branch is not evaluated. This
+/// determines which value the variable gets if both branches would have
+/// matched. In that case, it will always be the value from the left branch.
+///
+/// @description Checks that if the left branch matches, the right branch is not
+/// evaluated
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=patterns
+
+import "patterns_lib.dart";
+import "../../Utils/expect.dart";
+
+main() {
+  Shape shape1 = Square(1);
+  switch (shape1) {
+    case Square(area: var s) | Shape(area: var s):
+      Expect.equals("Square.area", shape1.log);
+      break;
+    default:
+      print("Other");
+  }
+
+  Shape shape2 = Square(2);
+  switch (shape2) {
+    case Square(area: 2) | Square(area: 4) | Square(area: 4):
+      Expect.equals("Circle.area=2;Circle.area=4;", shape2.log);
+      break;
+    default:
+      print("Other");
+  }
+
+  Shape shape3 = Shape();
+  switch (shape3) {
+    case Circle(area: 0) | Square(area: 1) | Shape(area: 0):
+      Expect.equals("Shape.area=0;", shape3.log);
+      break;
+    default:
+      print("Other");
+  }
+}

LanguageFeatures/Patterns/logical_or_A04_t02.dart

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+// Copyright (c) 2022, 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.
+
+/// @assertion logicalOrPattern ::= ( logicalOrPattern '|' )? logicalAndPattern
+///
+/// A pair of patterns separated by | matches if either of the branches match
+///
+/// A logical-or pattern may match even if one of its branches does not. That
+/// means that any variables in the non-matching branch would not be
+/// initialized. To avoid problems stemming from that, the following
+/// restrictions apply:
+///
+/// The two branches must define the same set of variables.
+///
+/// If the left branch matches, the right branch is not evaluated. This
+/// determines which value the variable gets if both branches would have
+/// matched. In that case, it will always be the value from the left branch.
+///
+/// @description Checks that if the left branch doesn't match, then the right
+/// branch is evaluated
+/// @author [email protected]
+
+// SharedOptions=--enable-experiment=patterns
+
+import "patterns_lib.dart";
+import "../../Utils/expect.dart";
+
+main() {
+  Shape shape1 = Square(1);
+  switch (shape1) {
+    case Square(area: 2) | Square(area: 1):
+      Expect.equals("Square.area=2;Square.area=1;", shape1.log);
+      break;
+    default:
+      print("Other");
+  }
+
+  Shape shape2 = Shape();
+  switch (shape2) {
+    case Square(area: 2) | Rectangle(area: 1) | Shape(area: 0):
+      Expect.equals("Shape.area=0;", shape2.log);
+      break;
+    default:
+      print("Other");
+  }
+
+  Shape shape3 = Circle(1);
+  switch (shape2) {
+    case Circle(area: 2) | Circle(area: 1) | Circle(area: 0)
+      | Circle(area: 3.14):
+      Expect.equals(
+          "Circle.area=2;Circle.area=1;Circle.area=0;Circle.area=3.14;",
+          shape3.log);
+      break;
+    default:
+      print("Other");
+  }
+
+  Shape shape4 = Rectangle(1, 2);
+  bool other = false;
+  switch (shape4) {
+    case Rectangle(area: 3) | Rectangle(area: 1) | Rectangle(area: 42):
+      Expect.fail("No branches should match");
+      break;
+    default:
+      other = true;
+      Expect.equals("Rectangle.area=3;Rectangle.area=1;Rectangle.area=42;",
+          shape4.log);
+  }
+  Expect.isTrue(other);
+}