Merge pull request #1 from aifarfa/reverse-words

Reverse words

Author: aifarfa

package.json

@@ -18,6 +18,7 @@
     "babel-core": "^6.18.2",
     "babel-preset-latest": "^6.16.0",
     "chai": "^3.5.0",
-    "mocha": "^3.2.0"
+    "mocha": "^3.2.0",
+    "testdouble": "^1.9.0"
   }
 }

src/reverse-words/B-large-practice.in

@@ -0,0 +1,6 @@
+5
+this is a test
+foobar
+all your base
+class
+pony along

src/reverse-words/B-small-practice.in

@@ -0,0 +1,6 @@
+import reverseWords from './reverse-words.js'
+import path from 'path'
+
+const args = process.argv.slice(2)
+const filename = args[0] || path.resolve('./src/reverse-words/B-large-practice.in')
+reverseWords(filename)

src/reverse-words/index.js

@@ -0,0 +1,19 @@
+import * as io from '../utils/io.js'
+
+const readLine = (txt) => txt.split('\n').slice(1)
+
+const notEmpty = txt => txt && txt.length
+
+export const reverseLine = (line) => line.split(' ').reverse().join(' ').trim()
+
+export const reverse = (data) => readLine(data).map(reverseLine).filter(notEmpty)
+
+export const formatOutput = (lines) => lines
+  .map((line, index) => `Case #${index + 1}: ${line}`)
+  .join(io.endOfLine())
+
+export default(file) => io.readAsString(file)
+  .then(reverse)
+  .then(formatOutput)
+  .then(result => io.writeFile(result))
+  // .catch(e => console.error(e))

src/reverse-words/reverse-words.js

@@ -0,0 +1,23 @@
+import * as fs from 'fs'
+import {EOL} from 'os'
+
+export const endOfLine = () => EOL
+
+const readAsync = (file) => (resolve, reject) => fs.readFile(file, (err, data) => {
+  if (err) {
+    reject(err)
+  } else {
+    resolve(data.toString())
+  }
+})
+
+const writeAsync = (text) => (resolve, reject) => fs.writeFile('output.log', text, (err) => {
+  if (err) {
+    reject(err)
+  } else {
+    resolve()
+  }
+})
+
+export const readAsString = (file) => new Promise(readAsync(file))
+export const writeFile = (text) => new Promise(writeAsync(text))

src/utils/io.js

@@ -0,0 +1,68 @@
+import {expect} from 'chai'
+import td from 'testdouble'
+import * as io from '../src/utils/io.js'
+import reverseWords, {reverse, reverseLine, formatOutput} from '../src/reverse-words/reverse-words.js'
+
+describe('reverse words', () => {
+
+  beforeEach(function(){
+    let eol = td.replace(io, 'endOfLine')
+    td.when(eol()).thenReturn('\n')
+  })
+
+  afterEach(function(){
+    td.reset()
+  })
+
+  it('inject EOL', () => {
+    const eol = io.endOfLine()
+    expect(eol).to.eq('\n')
+  })
+
+  it('reverse line', () => {
+    expect(reverseLine('this is a test')).to.eq('test a is this')
+  })
+
+  it('do not reverse single word', () => {
+    expect(reverseLine('foobar')).to.eq('foobar')
+  })
+
+  it('trim white space', () => {
+    expect(reverseLine('  bar bazz ')).to.eq('bazz bar')
+  })
+
+  it('formatOutput', () => {
+    const raw = ['foobar', 'boo', 'baz']
+    const result = formatOutput(raw)
+    expect(result).to.eq(`Case #1: foobar\nCase #2: boo\nCase #3: baz`)
+  })
+
+  it('reverse words order', () => {
+    const input = `3
+      this is a test
+      foobar
+      all your base`
+    const result = reverse(input)
+
+    expect(result).to.have.length(3)
+    expect(result[0]).to.eq('test a is this')
+    expect(result[1]).to.eq('foobar')
+    expect(result[2]).to.eq('base your all')
+  })
+
+  it('reverseWords', () => {
+    const readAsString = td.replace(io, 'readAsString')
+    const writeFile = td.replace(io, 'writeFile')
+    const input = `3
+      this is a test
+      foobar
+      all your base`
+
+    td.when(readAsString('input.file')).thenReturn(Promise.resolve(input))
+
+    return reverseWords('input.file').then(() => {
+      td.verify(writeFile(`Case #1: test a is this\nCase #2: foobar\nCase #3: base your all`))
+    })
+  })
+
+})