now reduce & reduceRight has strictly 3 parameters #14 & cb parameter…

… is simplified following #8

src/fn/reduce.js

@@ -1 +1,3 @@
-module.exports = require('../core/eager-method-factory.js')([].reduce, 3)
+module.exports = function (iterable, cb, initialValue) {
+    return [...iterable].reduce((acc, val) => cb(acc, val), initialValue)
+}

src/fn/reduceRight.js

@@ -1 +1,3 @@
-module.exports = require('../core/eager-method-factory.js')([].reduceRight, 3)
+module.exports = function (iterable, cb, initialValue) {
+    return [...iterable].reduceRight((acc, val) => cb(acc, val), initialValue)
+}

src/index.js

@@ -24,7 +24,6 @@ const every = require('./fn/every')
 const find = require('./fn/find')
 const findEntry = require('./fn/findEntry')
 const findIndex = require('./fn/findIndex')
-const forEach = require('./fn/forEach')
 const includes = require('./fn/includes')
 const indexOf = require('./fn/indexOf')
 const indexOfFrom = require('./fn/indexOfFrom')
@@ -41,8 +40,10 @@ const some = require('./fn/some')
 const take = require('./fn/take')
 
 const number = ['Number']
+const fnc = ['Function']
 const infiniteIterablesValidation = [[], [Iterable], Infinity]
-const functionValidation = [[], ['Function']]
+const functionValidation = [[], fnc]
+const reduceValidation = [[], fnc, []]
 const numberValidation = [[], number]
 const twoNumberValidation = [[], number, number]
 
@@ -97,9 +98,6 @@ const Iterum = factory({
             gen: flatten,
             validation: numberValidation
         },
-        forEach: {
-            fn: forEach
-        },
         includes: {
             fn: includes
         },
@@ -150,10 +148,12 @@ const Iterum = factory({
             validation: infiniteIterablesValidation
         },
         reduce: {
-            fn: reduce
+            fn: reduce,
+            validation: reduceValidation
         },
         reduceRight: {
-            fn: reduceRight
+            fn: reduceRight,
+            validation: reduceValidation
         },
         repeat: {
             gen: repeat,

test/fn/reduceRight_test.js

@@ -4,37 +4,40 @@ const Iterum = require('../../src/index.js')
 
 describe('reduceRight', function () {
     it('returns correct value', function () {
-        const cb = sinon.spy(function (a, b) {
-            return a - b
-        })
-        const value = Iterum([1, 3, 5])
-            .reduceRight(cb)
-        expect(value).to.be.deep.equal(1)
+        const cb = (a, b) => a - b
+        const value = Iterum([1, 3, 5]).reduceRight(cb, 0)
+        expect(value).to.be.deep.equal(-9)
     })
 
     it('without initial value', function () {
         const cb = sinon.spy(function (a, b) {
             return a + b
         })
         const iterum = Iterum([1, 3, 5])
-        iterum.reduceRight(cb)
+        iterum.reduceRight(cb, 0)
         expect(cb.args).to.be.deep.equal([
-            [5, 3, 1, iterum],
-            [8, 1, 0, iterum]
+            [0, 5],
+            [5, 3],
+            [8, 1]
         ])
     })
 
-    it('with initial value', function () {
-        const cb = sinon.spy(function (a, b) {
-            return a + b
+    describe('wrong arguments', function () {
+        it('throws an exception if parameters are not passed', function () {
+            function test () {
+                Iterum(new Set([1, 4, 2])).reduceRight()
+            }
+            expect(test).to.throw(TypeError,
+                /^undefined is not a function$/)
+        })
+
+        it('throws an exception if initial value parameter is not passed', function () {
+            function test () {
+                Iterum(new Set([1, 4, 2])).reduceRight((a, b) => a + b)
+            }
+            expect(test).to.throw(TypeError,
+                /^argument 2 is required$/)
         })
-        const iterum = Iterum([1, 3, 5])
-        iterum.reduceRight(cb, 0)
-        expect(cb.args).to.be.deep.equal([
-            [0, 5, 2, iterum],
-            [5, 3, 1, iterum],
-            [8, 1, 0, iterum]
-        ])
     })
 
     describe('static method', function () {

test/fn/reduce_test.js

@@ -4,37 +4,40 @@ const Iterum = require('../../src/index.js')
 
 describe('reduce', function () {
     it('returns correct value', function () {
-        const cb = sinon.spy(function (a, b) {
-            return a - b
-        })
-        const value = Iterum(Iterum([1, 3, 5]))
-            .reduce(cb)
-        expect(value).to.be.deep.equal(-7)
+        const cb = (a, b) => a - b
+        const value = Iterum([1, 3, 5]).reduce(cb, 0)
+        expect(value).to.be.deep.equal(-9)
     })
 
     it('without initial value', function () {
         const cb = sinon.spy(function (a, b) {
             return a + b
         })
-        const iterum = Iterum(Iterum([1, 3, 5]))
-        iterum.reduce(cb)
+        const iterum = Iterum([1, 3, 5])
+        iterum.reduce(cb, 0)
         expect(cb.args).to.be.deep.equal([
-            [1, 3, 1, iterum],
-            [4, 5, 2, iterum]
+            [0, 1],
+            [1, 3],
+            [4, 5]
         ])
     })
 
-    it('with initial value', function () {
-        const cb = sinon.spy(function (a, b) {
-            return a + b
+    describe('wrong arguments', function () {
+        it('throws an exception if parameters are not passed', function () {
+            function test () {
+                Iterum(new Set([1, 4, 2])).reduce()
+            }
+            expect(test).to.throw(TypeError,
+                /^undefined is not a function$/)
+        })
+
+        it('throws an exception if initial value parameter is not passed', function () {
+            function test () {
+                Iterum(new Set([1, 4, 2])).reduce((a, b) => a + b)
+            }
+            expect(test).to.throw(TypeError,
+                /^argument 2 is required$/)
         })
-        const iterum = Iterum(Iterum([1, 3, 5]))
-        iterum.reduce(cb, 0)
-        expect(cb.args).to.be.deep.equal([
-            [0, 1, 0, iterum],
-            [1, 3, 1, iterum],
-            [4, 5, 2, iterum]
-        ])
     })
 
     describe('static method', function () {