Merge pull request #1 from Floofies/master

Added `forField`, `subsetOf`, `is`, Refactor

Select.js

@@ -1,12 +1,11 @@
 'use strict';
-
 /**
- * Return a function based on a condition.
+* Return a function based on a condition.
- * Functional alternative to switch-case.
+* Functional alternative to switch-case.
- * @projectname Select-Return
+* @projectname Select-Return
- * @version 1.0.0
+* @version 1.0.0
- * @author Muthu Kumar (@MKRhere)
+* @author Muthu Kumar (MKRhere)
- */
+*/
 
 /**
  * Creates a SelectValue instance with a value and optional resolve function.
@@ -23,7 +22,6 @@ class SelectValue {
 		this.value = value;
 		if (resolve) this.resolve = (...args) => resolve(...args, value);
 	}
-
 	/**
 	 * Default resolve prototype. Returns null when called.
 	 * Used in case a resolve is never set.
@@ -36,61 +34,94 @@ class SelectValue {
 }
 
 /**
- * Creates a SelectIterable instance from an array.
+* Creates a SelectIterable instance from an array.
- * Created internally from Select.prototype.for, and not exported.
+* Created internally from Select.prototype.for, and not exported.
- * @class SelectIterable
+* @class SelectIterable
- */
+* @param {array} values - array created from Select.prototype.for
+* @param {Array<function>} tests - array of { test, consequent } objects
+* @param {function} tests[].test - test function
+* @param {function} tests[].consequent - consequent function
+* @constructs SelectIterable
+*/
 class SelectIterable {
-	/**
+	constructor(values, conditionals) {
-	 * @param {array} values - array created from Select.prototype.for
+		this.values = values.map(value => value instanceof SelectValue ? value : new SelectValue(value));
-	 * @param {Array<function>} tests - array of { test, consequent } objects
+		this.conditionals = conditionals;
-	 * @param {function} tests[].test - test function
-	 * @param {function} tests[].consequent - consequent function
-	 * @constructs SelectIterable
-	 */
-	constructor(values, tests) {
-		this.values = values
-			.map(x => x instanceof SelectValue
-				? x
-				: new SelectValue(x)
-			);
-		this.tests = tests;
 	}
-
 	/**
-	 * Accepts a test and consequent function each and returns a new
+	* Accepts a test and consequent function each and returns a new
-	 * SelectIterable instance.
+	*  SelectIterable instance.
-	 * @param {Test} test - test callback function
+	* SelectIterable.prototype.for works a little differently than
-	 * @param {function} consequent - consequent callback function
+	*  Select.prototype.for, by accumulating the tests and resolving all the
-	 * @returns {SelectIterable} - an instance of SelectIterable
+	*  values when .resolve() is called.
-	 * @memberof SelectIterable
+	* @param {callback} predicate  A test callback function.
-	 */
+	*	@callback predicate
-	for(test, consequent) {
+	*	@param {any} value   The Selected value.
-		/* SelectIterable.prototype.for works a little
+	*	@returns {boolean}   The Boolean result of the test.
-			differently than Select.prototype.for,
+	* @param {callback} consequent  consequent callback function
-			by accumulating the tests and resolving
+	*	@callback consequent
-			all the values when .resolve() is called */
+	*	@param {Array} args  An arbitrary Array of arguments.
+	*	@param {any} value   The Selected value.
+	*	@returns {any}
+	* @returns {SelectIterable}  an instance of SelectIterable
+	* @memberof SelectIterable
+	*/
+	if(predicate, consequent) {
+		return new SelectIterable(this.values, [
+			...this.conditionals,
+			{predicate, consequent}
+		]);
+	}
+	forField(...pairs) {
+		var pair;
+		var callback;
+		var even;
+		pairs.forEach((pair, index) => {
+			even = index % 2 === 0;
+			pair = this.conditionals[this.conditionals.length];
+			if (pair.length === 2) {
+				this.conditionals.push({});
+			};
+			callback = conditionals[loc];
+			if (typeof callback === "object") {
+				if (Array.isArray(callback)) {
+					pair.predicate = callback[0];
+					pair.consequent = callback[0];
+				} else {
+					Object.assign(pair, {
+						predicate: callback.predicate,
+						consequent: callback.consequent
+					});
+				}
+				continue;
+			}
+			if (even) pair.predicate = callback;
+			if (!even) pair.consequent = callback;
+		}, this);
 		return new SelectIterable(
-			this.values,
+			this.values, 
-			[ ...this.tests, { test, consequent } ]
+			[...this.conditionals, ...conditionals]
 		);
 	}
-
+	subset(value, consequent) {
-	resolve(...args) {
+		return this.if(this.value.every(element => element in value))
-		/* When .resolve() is called, a resolved value
+	}
-			is generated for each value in the array */
+	superset(value, consequent) {
-		return this.values.map(item => {
+		return this.if(value.every(element => element in this.value));
-			const resolver = this
-				.tests
-				.find(x => x.test(item.value)
-					? x.consequent
-					: null);
-			return resolver
-				? resolver.consequent(...args, item.value)
-				: null;
-		});
 	}
 }
+SelectIterable.prototype.resolve = function (...args) {
+	return this.values.map(item => {
+		const resolver = this.conditionals.find(conditional =>
+			conditional.predicate(item.value)
+				? conditional.consequent
+				: null
+		);
+		return resolver
+			? resolver.consequent(...args, this.value)
+			: null;
+	}, this);
+};
 
 /**
  * Creates a new Select instance.
@@ -107,33 +138,46 @@ class Select extends SelectValue {
 		super(value, resolve);
 		this.iterable = typeof value === "object" && Symbol.iterator in value;
 	}
-
 	/**
-	 * Accepts a test and consequent function each and returns a new
+	* Accepts a test and consequent function each and returns a new
-	 * Select or SelectIterable instance.
+	* Select or SelectIterable instance.
-	 * @param {function} test - test callback function
+	* @param {callback} predicate  A test callback function.
-	 * @param {function} consequent - consequent callback function
+	*	@callback predicate
-	 * @returns {Select|SelectIterable} - Returns a SelectIterable instance
+	*	@param {any} value   The Selected value.
-	 * if value was array, or a Select instance otherwise
+	*	@returns {boolean}   The Boolean result of the test.
-	 * @memberof Select
+	* @param {callback} consequent  consequent callback function
-	 */
+	*	@callback consequent
-	for(test, consequent) {
+	*	@param {Array} args  An arbitrary Array of arguments.
+	*	@param {any} value   The Selected value.
+	*	@returns {any}
+	* @returns {(Select|SelectIterable)} - Returns a SelectIterable instance
+	*  if value was array, or a Select instance otherwise
+	* @memberof Select
+	*/
+	if(predicate, consequent) {
 		if (this.iterable) {
-			/* If the value passed to the constructor is
+			/* If the value passed to the constructor is an
-				an array, initialise a new SelectIterable
+			 iterable, return a new SelectIterable using the
-				with the array and { test, consequent } pair
+			 iterable and { test, consequent } pair.*/
-				and return */
 			return new SelectIterable(
 				Array.from(this.value),
-				[ { test, consequent } ],
+				[{ predicate, consequent }]
 			);
 		}
-		if (test(this.value)) return new Select(this.value, consequent);
+		if (predicate(this.value)) {
+			return new Select(this.value, consequent);
+		}
 		/* If the test doesn't pass, just pass the Select
 			instance along the chain until a test passes,
 			or .resolve() is called */
 		return this;
 	}
+	is(value, consequent) {
+		return this.if(value === this.value, consequent);
+	}
+	isNot(value, consequent) {
+		return this.if(value !== this.value, consequent)
+	}
 }
 
 module.exports = Select;

spec/SelectArraySpec.js

@@ -11,14 +11,15 @@ describe("Select", () => {
 		const a = [ 10, 20, 0, 'UnexpectedString' ];
 
 		const result = new Select(a)
-			.for(x => x > 10, () => 'Greater than 10')
+			.if(x => x > 10, () => 'Greater than 10')
-			.for(x => x < 10, () => 'Lesser than 10')
+			.if(x => x < 10, () => 'Lesser than 10')
-			.for(x => x === 10, () => `Is 10`);
+			.if(x => x === 10, () => `Is 10`);
-
+		console.log(result.resolve());
-		expect(result.resolve())
+		expect(result.resolve()).toEqual([ 
-			.toEqual([ 'Is 10',
+			'Is 10',
-				'Greater than 10',
+			'Greater than 10',
-				'Lesser than 10',
+			'Lesser than 10',
-				null ]);
+			null
+		]);
 	});
 });

spec/SelectSpec.js

@@ -9,9 +9,9 @@ describe("Select", () => {
 		const a = 10;
 
 		const result = new Select(a)
-			.for(x => x > 10, () => 'Greater than 10')
+			.if(x => x > 10, () => 'Greater than 10')
-			.for(x => x < 10, () => 'Lesser than 10')
+			.if(x => x < 10, () => 'Lesser than 10')
-			.for(x => x === 10, () => 'Is 10');
+			.if(x => x === 10, () => 'Is 10');
 
 		expect(result.resolve()).toBe('Is 10');
 	});
@@ -20,9 +20,9 @@ describe("Select", () => {
 		const a = 1;
 
 		const result = new Select(a)
-			.for(x => x > 10, () => 'Greater than 10')
+			.if(x => x > 10, () => 'Greater than 10')
-			.for(x => x < 10, () => 'Lesser than 10')
+			.if(x => x < 10, () => 'Lesser than 10')
-			.for(x => x === 10, () => `Is 10`);
+			.if(x => x === 10, () => `Is 10`);
 
 		expect(result.resolve()).toBe('Lesser than 10');
 	});
@@ -31,9 +31,9 @@ describe("Select", () => {
 		const a = 100;
 
 		const result = new Select(a)
-			.for(x => x > 10, () => 'Greater than 10')
+			.if(x => x > 10, () => 'Greater than 10')
-			.for(x => x < 10, () => 'Lesser than 10')
+			.if(x => x < 10, () => 'Lesser than 10')
-			.for(x => x === 10, () => `Is 10`);
+			.if(x => x === 10, () => `Is 10`);
 
 		expect(result.resolve()).toBe('Greater than 10');
 	});
@@ -42,9 +42,9 @@ describe("Select", () => {
 		const a = 'UnexpectedString';
 
 		const result = new Select(a)
-			.for(x => x > 10, () => 'Greater than 10')
+			.if(x => x > 10, () => 'Greater than 10')
-			.for(x => x < 10, () => 'Lesser than 10')
+			.if(x => x < 10, () => 'Lesser than 10')
-			.for(x => x === 10, () => `Is 10`);
+			.if(x => x === 10, () => `Is 10`);
 
 		expect(result.resolve()).toBe(null);
 	});