test: add tests for forEach method in dstructs/named-typed-tuple

lib/node_modules/@stdlib/dstructs/named-typed-tuple/test/test.for_each.js

@@ -0,0 +1,188 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var hasProp = require( '@stdlib/assert/has-property' );
+var isFunction = require( '@stdlib/assert/is-function' );
+var namedtypedtuple = require( './../lib' );
+
+
+// TESTS //
+
+tape( 'main export is a function', function test( t ) {
+	t.ok( true, __filename );
+	t.strictEqual( typeof namedtypedtuple, 'function', 'main export is a function' );
+	t.end();
+});
+
+tape( 'a tuple has a `forEach` method', function test( t ) {
+	var Point;
+	var p;
+
+	Point = namedtypedtuple( [ 'x', 'y' ] );
+	p = new Point();
+
+	t.strictEqual( hasProp( p, 'forEach' ), true, 'returns expected value' );
+	t.strictEqual( isFunction( p.forEach ), true, 'returns expected value' );
+	t.end();
+});
+
+tape( 'the method throws an error if invoked with a `this` context which is not a tuple instance', function test( t ) {
+	var values;
+	var Point;
+	var p;
+	var i;
+
+	Point = namedtypedtuple( [ 'x', 'y' ] );
+	p = new Point( [ 1, 2 ] );
+
+	values = [
+		'5',
+		5,
+		NaN,
+		true,
+		false,
+		null,
+		void 0,
+		{},
+		[],
+		function noop() {}
+	];
+	for ( i = 0; i < values.length; i++ ) {
+		t.throws( badValue( values[i] ), TypeError, 'throws an error when provided '+values[i] );
+	}
+	t.end();
+
+	function badValue( value ) {
+		return function badValue() {
+			return p.forEach.call( value, fcn );
+		};
+	}
+
+	function fcn( v ) {
+		void v;
+	}
+});
+
+tape( 'the method throws an error if provided a first argument which is not a function', function test( t ) {
+	var values;
+	var Point;
+	var p;
+	var i;
+
+	Point = namedtypedtuple( [ 'x', 'y' ] );
+	p = new Point( [ 1, 2 ] );
+
+	values = [
+		'5',
+		3.14,
+		NaN,
+		true,
+		false,
+		null,
+		void 0,
+		{},
+		[]
+	];
+	for ( i = 0; i < values.length; i++ ) {
+		t.throws( badValue( values[i] ), TypeError, 'throws an error when provided '+values[i] );
+	}
+	t.end();
+
+	function badValue( value ) {
+		return function badValue() {
+			return p.forEach( value );
+		};
+	}
+});
+
+tape( 'the method returns `undefined`', function test( t ) {
+	var Point;
+	var out;
+	var p;
+
+	Point = namedtypedtuple( [ 'x', 'y' ] );
+	p = new Point( [ 10, 20 ] );
+	out = p.forEach( fcn );
+
+	t.strictEqual( out, void 0, 'returns expected value' );
+	t.end();
+
+	function fcn( v ) {
+		return v;
+	}
+});
+
+tape( 'the method invokes a provided function for each element in a tuple', function test( t ) {
+	var fieldNames;
+	var indices;
+	var values;
+	var tuples;
+	var Point;
+	var p;
+
+	indices = [];
+	values = [];
+	fieldNames = [];
+	tuples = [];
+
+	Point = namedtypedtuple( [ 'x', 'y', 'z' ] );
+	p = new Point( [ 1, 2, 3 ] );
+	p.forEach( fcn );
+
+	t.deepEqual( values, [ 1, 2, 3 ], 'returns expected values' );
+	t.deepEqual( indices, [ 0, 1, 2 ], 'returns expected indices' );
+	t.deepEqual( fieldNames, [ 'x', 'y', 'z' ], 'returns expected field names' );
+	t.strictEqual( tuples[ 0 ], p, 'returns expected tuple reference' );
+	t.strictEqual( tuples[ 1 ], p, 'returns expected tuple reference' );
+	t.strictEqual( tuples[ 2 ], p, 'returns expected tuple reference' );
+
+	t.end();
+
+	function fcn( v, i, fieldName, tuple ) {
+		values.push( v );
+		indices.push( i );
+		fieldNames.push( fieldName );
+		tuples.push( tuple );
+	}
+});
+
+tape( 'the method supports providing an execution context', function test( t ) {
+	var Point;
+	var ctx;
+	var p;
+
+	ctx = {
+		'count': 0
+	};
+	Point = namedtypedtuple( [ 'x', 'y', 'z' ] );
+	p = new Point( [ 1, 2, 3 ] );
+	p.forEach( fcn, ctx );
+
+	t.strictEqual( ctx.count, 3, 'returns expected value' );
+
+	t.end();
+
+	function fcn() {
+		this.count += 1; // eslint-disable-line no-invalid-this
+	}
+});