Jasmine test cases - "these" - version 2 (supporting message templates)

jasmine-these-2 usage examples.js

describe("typeof", function() {
	// You can pass in an object of test cases:
	these("should output {1} when the input is ", {
		"any number": [ 0, "number" ],
		"NaN": [ NaN, "number" ],
		"undefined": [ undefined, "undefined" ],
		"null": [ null, "object" ],
		"a Date": [ new Date(), "object" ],
		"anon object": [ {}, "object" ],
		"anon function": [ function(){}, "object" ],
	}, function(input, expectedOutput) {
		var actualOutput = typeof input;
		expect(actualOutput).toBe(expectedOutput);
	});
	// Generates the following `it` statements:
	// it("should output \"number\" when the input is any number", ...)
	// it("should output \"number\" when the input is NaN", ...)
	// ...
	// it("should output \"object\" when the input is anon function", ...)
	


	// You can pass in an array of test cases:
	these("expects {0} to output {1}", [
		[ 0, "number" ],
		[ NaN, "number" ],
		[ undefined, "undefined" ],
		[ null, "object" ],
		[ new Date(), "object" ],
		[ {}, "object" ],
		[ function(){}, "object" ],
	], function(input, expectedOutput) {
		var actualOutput = typeof input;
		expect(actualOutput).toBe(expectedOutput);
	});
	// Generates the following `it` statements:
	// it("expects 0 to output \"number\"", ...)
	// it("expects NaN to output \"number\"", ...)
	// ...
	// it("expects function(){} to output \"object\", ...)
	
	
	
});

jasmine-these-2.js

/**
 * Creates a bunch of "it" blocks, one for each test case.
 *
 * @param {String} desc - Describes each test case
 * @param {Object.<string, Array>|Array.<Array>} testCases
 * @param {String} testCases.<key> - Describes the test case
 * @param {Array} testCases.<value> - An array of args that will be passed to the test
 * @param {Function} test - This test will be called once for each test case.
 */
function these(desc, testCases, test) {
    _these(desc, testCases, test, it);
}
function xthese(desc, testCases, test) {
    _these(desc, testCases, test, xit);
}
function _these(desc, testCases, test, it) {
    if (Array.isArray(testCases)) {
        testCases.forEach(function(testCaseArgs) {
            var description = _getDescription(desc, testCaseArgs);
            it(description, _getTestCallback(test, testCaseArgs));
        });
    } else {
        Object.keys(testCases).forEach(function (testCaseName) {
            var testCaseArgs = testCases[testCaseName];
            var description = _getDescription(desc + testCaseName, testCaseArgs);
            it(description, _getTestCallback(test, testCaseArgs));
        });
    }

}
function _getTestCallback(test, testCaseArgs) {
    // The callback passed to `it` can contain a "done" parameter for async calls.
    // Let's ensure we include that parameter here:
    if (test.length === 0 ) {
        return function() {
            return test.apply(null, testCaseArgs);
        };
    } else {
        return function(done) {
            return test.apply(null, testCaseArgs.concat([ done ]) );
        };
    }
}
function _getDescription(desc, testCaseArgs) {
    // Treat the description as a template, and replace {0} or {1} with arg[0] or arg[1]:
    return desc.replace(/\{(\d+)\}/g, function($0, $1) {
        var index = parseInt($1, 10);
        if (index >= testCaseArgs.length) return $0; // Invalid index
        var value = testCaseArgs[index];
        var prettyResult =
            // Values that don't look good with JSON.stringify:
            (value === undefined) ? "undefined"
                : (typeof value === 'function') ? (value.name || value.toString() ) // Print the function's name or body
                : (typeof value === 'number') ? value.toString() //	Works better for NaN or Infinity
                : JSON.stringify(value);
        return prettyResult;
    });
}