Fixes, new operators, code coverage, and deprecations

* Add downloads badge
* Add $strLenBytes, $strLenCP, $substrCP, $substrBytes
* Fix $indexOfBytes
* Fix $stdDevSamp
* Fix $in to handle arguments correctly and use aggregation semantics
* Fix string operators.
* Add code coverage tool
* Remove max and min cursor methods
* Restrict custom query operator type `OP_QUERY` to return boolean only
* Remove contributors file
* Add istanbul plugin to babelrc

.babelrc

@@ -6,5 +6,10 @@
   ],
   "plugins": [
     "external-helpers"
-  ]
+  ],
+  "env": {
+    "test": {
+      "plugins": ["istanbul"]
+    }
+  }
 }

.gitignore

@@ -1,4 +1,5 @@
 .*
+coverage/
 dist/
 node_modules
 npm-debug.log

.npmignore

@@ -1,4 +1,4 @@
 .*
 node_modules/
+coverage/
 coverage.lcov
-coverage

CHANGELOG.md

@@ -3,7 +3,6 @@ Changelog
 ## 1.3.3 / 2017-08-02
 - Fix `computeValue` not overriding group operator keys after resolving expression
 - Added `$in`, `$objectToArray`, and `$arrayToObject` array aggregation operators
-- Minor refactoring
 
 ## 1.3.2 / 2017-07-28
 - Restore `setup` function. https://github.com/kofrasa/mingo/issues/56
@@ -30,7 +29,6 @@ Changelog
 ## v1.1.2 / 2017-03-30
 - Optimize `$lookup` implementation
 - Avoid reversing original input to `$reverseArray`
-- Refactor some methods
 
 ## v1.1.1 / 2017-03-12
 - Fix incorrect method call for ObjectProto

Makefile

@@ -4,12 +4,7 @@ MODULE = mingo
 VERSION = $(shell cat VERSION)
 YEAR = $(shell date +%Y)
 BANNER = templates/header.txt
-
-# tools
-NODE_MODULES = ./node_modules
-ROLLUP = ${NODE_MODULES}/rollup/bin/rollup
-UGLIFY = ${NODE_MODULES}/uglify-js/bin/uglifyjs
-
+TEST_FILES = $(shell find test -name "*.js")
 
 all: clean test build
 
@@ -19,7 +14,7 @@ build: prepare build.es6 compress bower.json package.json
 
 
 build.es6:
-	@${ROLLUP} -c config/rollup.es.js
+	@node_modules/.bin/rollup -c config/rollup.es.js
 
 
 prepare:
@@ -28,7 +23,7 @@ prepare:
 
 compress: mingo.js
 	@cat ${BANNER} | sed "s/@VERSION/${VERSION}/" | sed "s/@YEAR/${YEAR}/" > dist/${MODULE}.min.js
-	@${UGLIFY} dist/${MODULE}.js --compress --mangle --source-map dist/${MODULE}.map >> dist/${MODULE}.min.js
+	@node_modules/.bin/uglifyjs dist/${MODULE}.js --compress --mangle --source-map dist/${MODULE}.min.map >> dist/${MODULE}.min.js
 	@gzip -kf dist/${MODULE}.min.js
 
 
@@ -39,11 +34,11 @@ clean:
 
 
 mingo.js:
-	@${ROLLUP} -c config/rollup.umd.js
+	@node_modules/.bin/rollup -c config/rollup.umd.js
 
 
 test: mingo.js
-	@tape test/*.js
+	@node_modules/.bin/nyc --reporter=lcov --reporter=text node_modules/.bin/tape ${TEST_FILES}
 
 
 %.json: templates/%.json.txt

README.md

@@ -3,6 +3,7 @@ JavaScript implementation of MongoDB query language
 
 [![version](https://img.shields.io/npm/v/mingo.svg)](https://www.npmjs.org/package/mingo)
 [![build status](https://secure.travis-ci.org/kofrasa/mingo.png)](http://travis-ci.org/kofrasa/mingo)
+[![npm](https://img.shields.io/npm/dt/mingo.svg)]()
 
 ## Install
 ```$ npm install mingo```
@@ -51,7 +52,7 @@ var mingo = require('mingo')
 ```
 
 For the browser
-```
+```html
 // minified UMD module
 <script type="text/javascript" src="./dist/mingo.min.js"></script>
 
@@ -65,9 +66,10 @@ Tiny configuration if needed
 mingo.setup({
     key: '_id' // default
 });
-
+```
 
 ## Using query object to test objects
+```js
 // create a query with criteria
 // find all grades for homework with score >= 50
 let query = new mingo.Query({

lib/constants.js

@@ -21,4 +21,4 @@ export const OP_AGGREGATE = 'aggregate'
 export const OP_GROUP = 'group'
 export const OP_PIPELINE = 'pipeline'
 export const OP_PROJECTION = 'projection'
-export const OP_QUERY = 'query'
+export const OP_QUERY = 'query'

lib/cursor.js

@@ -133,24 +133,6 @@ export class Cursor {
     return this.count() > this.__position
   }
 
-  /**
-   * Specifies the exclusive upper bound for a specific field
-   * @param expr
-   * @returns {Number}
-   */
-  max (expr) {
-    return groupOperators.$max(this._fetch(), expr)
-  }
-
-  /**
-   * Specifies the inclusive lower bound for a specific field
-   * @param expr
-   * @returns {Number}
-   */
-  min (expr) {
-    return groupOperators.$min(this._fetch(), expr)
-  }
-
   /**
    * Applies a function to each document in a cursor and collects the return values in an array.
    * @param callback

lib/index.js

@@ -1,4 +1,3 @@
-import './polyfill'
 import { OP_AGGREGATE, OP_GROUP, OP_PIPELINE, OP_PROJECTION, OP_QUERY } from './constants'
 import { _internal, setup } from './internal'
 import { Query, find, remove } from './query'

lib/internal.js

@@ -191,8 +191,6 @@ export function resolve (obj, selector, deepFlag = false) {
  * @param selector {String} dot separated path to field
  */
 export function resolveObj (obj, selector) {
-  if (isNil(obj)) return
-
   let names = selector.split('.')
   let key = names[0]
   // get the next part of the selector
@@ -430,7 +428,7 @@ export function slice (xs, skip, limit = null) {
     assert(limit > 0, 'Invalid argument value for $slice operator. Limit must be a positive number')
     limit += skip
   }
-  return Array.prototype.slice.apply(xs, [skip, limit])
+  return xs.slice(skip, limit)
 }
 
 /**
@@ -441,9 +439,9 @@ export function slice (xs, skip, limit = null) {
 export function stddev (ctx) {
   let sum = reduce(ctx.data, (acc, n) => acc + n, 0)
   let N = ctx.data.length || 1
-  let correction = ctx.sampled === true ? 1 : 0
-  let avg = sum / (N - correction)
-  return Math.sqrt(reduce(ctx.data, (acc, n) => acc + Math.pow(n - avg, 2), 0) / N)
+  let correction = (ctx.sampled && 1) || 0
+  let avg = sum / N
+  return Math.sqrt(reduce(ctx.data, (acc, n) => acc + Math.pow(n - avg, 2), 0) / (N - correction))
 }
 
 /**
@@ -467,16 +465,15 @@ export function redactObj (obj, expr, opt = {}) {
  */
 export function _internal () {
   return {
-    computeValue,
-    idKey,
-    ops,
-    resolve,
     assert,
+    computeValue,
     clone,
     each,
     err,
     getType,
     has,
+    idKey,
+    includes: inArray.bind(null),
     isArray,
     isBoolean,
     isDate,
@@ -491,6 +488,8 @@ export function _internal () {
     isString,
     isUndefined,
     keys,
-    map
+    map,
+    ops,
+    resolve
   }
 }

lib/operators/aggregation/arithmetic.js

@@ -6,6 +6,7 @@ export const arithmeticOperators = {
   /**
    * Returns the absolute value of a number.
    * https://docs.mongodb.com/manual/reference/operator/aggregation/abs/#exp._S_abs
+   *
    * @param obj
    * @param expr
    * @return {Number|null|NaN}
@@ -36,9 +37,8 @@ export const arithmeticOperators = {
    */
   $ceil (obj, expr) {
     let arg = computeValue(obj, expr)
-    if (isNaN(arg)) return NaN
     if (isNil(arg)) return null
-    assert(isNumber(arg), '$ceil must be a valid expression that resolves to a number.')
+    assert(isNumber(arg) || isNaN(arg), '$ceil must be a valid expression that resolves to a number.')
     return Math.ceil(arg)
   },
 
@@ -63,9 +63,8 @@ export const arithmeticOperators = {
    */
   $exp (obj, expr) {
     let arg = computeValue(obj, expr)
-    if (isNaN(arg)) return NaN
     if (isNil(arg)) return null
-    assert(isNumber(arg), '$exp must be a valid expression that resolves to a number.')
+    assert(isNumber(arg) || isNaN(arg), '$exp must be a valid expression that resolves to a number.')
     return Math.exp(arg)
   },
 
@@ -78,9 +77,8 @@ export const arithmeticOperators = {
    */
   $floor (obj, expr) {
     let arg = computeValue(obj, expr)
-    if (isNaN(arg)) return NaN
     if (isNil(arg)) return null
-    assert(isNumber(arg), '$floor must be a valid expression that resolves to a number.')
+    assert(isNumber(arg) || isNaN(arg), '$floor must be a valid expression that resolves to a number.')
     return Math.floor(arg)
   },
 
@@ -93,9 +91,8 @@ export const arithmeticOperators = {
    */
   $ln (obj, expr) {
     let arg = computeValue(obj, expr)
-    if (isNaN(arg)) return NaN
     if (isNil(arg)) return null
-    assert(isNumber(arg), '$ln must be a valid expression that resolves to a number.')
+    assert(isNumber(arg) || isNaN(arg), '$ln must be a valid expression that resolves to a number.')
     return Math.log(arg)
   },
 
@@ -109,9 +106,8 @@ export const arithmeticOperators = {
   $log (obj, expr) {
     let args = computeValue(obj, expr)
     assert(isArray(args) && args.length === 2, '$log must be a valid expression that resolves to an array of 2 items')
-    if (args.some(isNaN)) return NaN
     if (args.some(isNil)) return null
-    assert(args.every(isNumber), '$log expression must resolve to array of 2 numbers')
+    assert(args.some(isNaN) || args.every(isNumber), '$log expression must resolve to array of 2 numbers')
     return Math.log10(args[0]) / Math.log10(args[1])
   },
 
@@ -124,9 +120,8 @@ export const arithmeticOperators = {
    */
   $log10 (obj, expr) {
     let arg = computeValue(obj, expr)
-    if (isNaN(arg)) return NaN
     if (isNil(arg)) return null
-    assert(isNumber(arg), '$log10 must be a valid expression that resolves to a number.')
+    assert(isNumber(arg) || isNaN(arg), '$log10 must be a valid expression that resolves to a number.')
     return Math.log10(arg)
   },
 
@@ -179,9 +174,8 @@ export const arithmeticOperators = {
    */
   $sqrt (obj, expr) {
     let n = computeValue(obj, expr)
-    if (isNaN(n)) return NaN
     if (isNil(n)) return null
-    assert(isNumber(n) && n > 0, '$sqrt expression must resolve to non-negative number.')
+    assert(isNumber(n) && n > 0 || isNaN(n), '$sqrt expression must resolve to non-negative number.')
     return Math.sqrt(n)
   },
 
@@ -206,9 +200,8 @@ export const arithmeticOperators = {
    */
   $trunc (obj, expr) {
     let n = computeValue(obj, expr)
-    if (isNaN(n)) return NaN
     if (isNil(n)) return null
-    assert(isNumber(n) && n > 0, '$trunc must be a valid expression that resolves to a non-negative number.')
+    assert(isNumber(n) || isNaN(n), '$trunc expression must resolve to a number.')
     return Math.trunc(n)
   }
 }