add tests for reduce

test/built-ins/Iterator/prototype/reduce/argument-effect-order.js

@@ -0,0 +1,58 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Arguments and this value are evaluated in the correct order
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+includes: [compareArray.js]
+features: [iterator-helpers]
+flags: []
+---*/
+let effects = [];
+
+assert.throws(TypeError, function () {
+  Iterator.prototype.reduce.call(
+    {
+      get next() {
+        effects.push('get next');
+        return function () {
+          return { done: true, value: undefined };
+        };
+      },
+    },
+    {
+      valueOf() {
+        effects.push('reducer valueOf');
+      }
+    },
+    {
+      valueOf() {
+        effects.push('initial value valueOf');
+      }
+    }
+  );
+});
+
+assert.compareArray(effects, []);
+
+Iterator.prototype.reduce.call(
+  {
+    get next() {
+      effects.push('get next');
+      return function () {
+        return { done: true, value: undefined };
+      };
+    },
+  },
+  () => {},
+  {
+    valueOf() {
+      effects.push('initial value valueOf');
+    }
+  }
+);
+
+assert.compareArray(effects, ['get next']);

test/built-ins/Iterator/prototype/reduce/callable.js

@@ -0,0 +1,13 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Iterator.prototype.reduce is callable
+features: [iterator-helpers]
+---*/
+function* g() {}
+Iterator.prototype.reduce.call(g(), () => {}, 0);
+
+let iter = g();
+iter.reduce(() => {}, 0);

test/built-ins/Iterator/prototype/reduce/get-next-method-only-once.js

@@ -0,0 +1,36 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Gets the next method from the iterator only once
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+let nextGets = 0;
+
+class TestIterator extends Iterator {
+  get next() {
+    ++nextGets;
+    let counter = 5;
+    return function () {
+      if (counter <= 0) {
+        return { done: true, value: undefined };
+      } else {
+        return { done: false, value: --counter };
+      }
+    };
+  }
+}
+
+let iterator = new TestIterator();
+
+assert.sameValue(nextGets, 0);
+assert.sameValue(
+  iterator.reduce(x => x),
+  4
+);
+assert.sameValue(nextGets, 1);

test/built-ins/Iterator/prototype/reduce/get-next-method-throws.js

@@ -0,0 +1,23 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Iterator has throwing next getter
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+class IteratorThrows extends Iterator {
+  get next() {
+    throw new Test262Error();
+  }
+}
+
+let iterator = new IteratorThrows();
+
+assert.throws(Test262Error, function () {
+  iterator.reduce(() => {});
+});

test/built-ins/Iterator/prototype/reduce/is-function.js

@@ -0,0 +1,10 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Iterator.prototype.reduce is a built-in function
+features: [iterator-helpers]
+---*/
+
+assert.sameValue(typeof Iterator.prototype.reduce, 'function');

test/built-ins/Iterator/prototype/reduce/iterator-already-exhausted-initial-value.js

@@ -0,0 +1,21 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Iterator.prototype.reduce returns the initial value when the iterator has already been exhausted
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+let iterator = (function* () {})();
+
+let { value, done } = iterator.next();
+assert.sameValue(value, undefined);
+assert.sameValue(done, true);
+
+const initialValue = {};
+let result = iterator.reduce(() => {}, initialValue);
+assert.sameValue(result, initialValue);

test/built-ins/Iterator/prototype/reduce/iterator-already-exhausted-no-initial-value.js

@@ -0,0 +1,21 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Iterator.prototype.reduce without an initial value throws when the iterator has already been exhausted
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+let iterator = (function* () {})();
+
+let { value, done } = iterator.next();
+assert.sameValue(value, undefined);
+assert.sameValue(done, true);
+
+assert.throws(TypeError, function() {
+  iterator.reduce(() => {});
+});

test/built-ins/Iterator/prototype/reduce/iterator-yields-once-initial-value.js

@@ -0,0 +1,35 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Iterator.prototype.reduce calls reducer once for each value yielded by the underlying iterator when passed an initial value
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+function* g() {
+  yield 'a';
+}
+
+let iter = g();
+
+let assertionCount = 0;
+let initialValue = {};
+let result = iter.reduce((memo, v, count) => {
+  switch (v) {
+    case 'a':
+      assert.sameValue(memo, initialValue);
+      assert.sameValue(count, 0);
+      break;
+    default:
+      throw new Error();
+  }
+  ++assertionCount;
+  return v;
+}, initialValue);
+
+assert.sameValue(result, 'a');
+assert.sameValue(assertionCount, 1);

test/built-ins/Iterator/prototype/reduce/iterator-yields-once-no-initial-value.js

@@ -0,0 +1,26 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Iterator.prototype.reduce calls reducer once for each value yielded by the underlying iterator except the first when not passed an initial value
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+function* g() {
+  yield 'a';
+}
+
+let iter = g();
+
+let assertionCount = 0;
+let result = iter.reduce((memo, v, count) => {
+  ++assertionCount;
+  return v;
+});
+
+assert.sameValue(result, 'a');
+assert.sameValue(assertionCount, 0);

test/built-ins/Iterator/prototype/reduce/length.js

@@ -0,0 +1,22 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Iterator.prototype.reduce has a "length" property whose value is 1.
+info: |
+  ECMAScript Standard Built-in Objects
+
+  Unless otherwise specified, the length property of a built-in
+  Function object has the attributes { [[Writable]]: false, [[Enumerable]]:
+  false, [[Configurable]]: true }.
+features: [iterator-helpers]
+includes: [propertyHelper.js]
+---*/
+
+verifyProperty(Iterator.prototype.reduce, 'length', {
+  value: 1,
+  writable: false,
+  enumerable: false,
+  configurable: true,
+});

test/built-ins/Iterator/prototype/reduce/name.js

@@ -0,0 +1,29 @@
+// Copyright (C) 2020 Rick Waldron. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  The "name" property of Iterator.prototype.reduce
+info: |
+  17 ECMAScript Standard Built-in Objects
+
+  Every built-in Function object, including constructors, that is not
+  identified as an anonymous function has a name property whose value is a
+  String. Unless otherwise specified, this value is the name that is given to
+  the function in this specification.
+
+  ...
+
+  Unless otherwise specified, the name property of a built-in Function
+  object, if it exists, has the attributes { [[Writable]]: false,
+  [[Enumerable]]: false, [[Configurable]]: true }.
+features: [iterator-helpers]
+includes: [propertyHelper.js]
+---*/
+
+verifyProperty(Iterator.prototype.reduce, 'name', {
+  value: 'reduce',
+  writable: false,
+  enumerable: false,
+  configurable: true,
+});

test/built-ins/Iterator/prototype/reduce/next-method-returns-non-object.js

@@ -0,0 +1,23 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Underlying iterator next returns non-object
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+class NonObjectIterator extends Iterator {
+  next() {
+    return null;
+  }
+}
+
+let iterator = new NonObjectIterator();
+
+assert.throws(TypeError, function () {
+  iterator.reduce(() => {});
+});

test/built-ins/Iterator/prototype/reduce/next-method-returns-throwing-done.js

@@ -0,0 +1,31 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Underlying iterator next returns object with throwing done getter
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+class ThrowingIterator extends Iterator {
+  next() {
+    return {
+      get done() {
+        throw new Test262Error();
+      },
+      value: 1,
+    };
+  }
+  return() {
+    throw new Error();
+  }
+}
+
+let iterator = new ThrowingIterator();
+
+assert.throws(Test262Error, function () {
+  iterator.reduce(() => {});
+});

test/built-ins/Iterator/prototype/reduce/next-method-returns-throwing-value-done.js

@@ -0,0 +1,28 @@
+// Copyright (C) 2023 Michael Ficarra. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-iteratorprototype.reduce
+description: >
+  Underlying iterator next returns object with throwing value getter, but is already done
+info: |
+  %Iterator.prototype%.reduce ( reducer )
+
+features: [iterator-helpers]
+flags: []
+---*/
+class ThrowingIterator extends Iterator {
+  next() {
+    return {
+      done: true,
+      get value() {
+        throw new Test262Error();
+      },
+    };
+  }
+  return() {
+    throw new Error();
+  }
+}
+
+let iterator = new ThrowingIterator();
+iterator.reduce(() => {}, 0);