Removed bug when solving +2 resulted in -2 and added more test for er…

…ror catching)

bower.json

@@ -1,6 +1,6 @@
 {
   "name": "math-expression-evaluator",
-  "version": "1.0.2",
+  "version": "1.2.13",
   "description": "A flexible math expression evaluator",
   "main": "dist/browser/math-expression-evaluator.js",
   "keywords": [

dist/browser/math-expression-evaluator.js

@@ -1,5 +1,5 @@
-/** math-expression-evaluator version 1.2.13
- Dated:2016-08-23 */
+/** math-expression-evaluator version 1.2.14
+ Dated:2016-08-25 */
 
 (function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.mexp = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
 /**
@@ -505,6 +505,7 @@ var indexOf = require('lodash.indexof');
 				throw(new Mexp.exception("Can't understand after "+inpStr.slice(i)));
 			}
 			var index=indexOf(token,key);
+			var cToken=key;
 			var cType=type[index];
 			var cEv=eva[index];
 			var cPre=preced[cType];
@@ -625,12 +626,15 @@ var indexOf = require('lodash.indexof');
 						inc(ptc,1);
 					}
 				}
-				else if(pre.type!==5&&pre.type!==7&&pre.type!==1&&pre.type!==3&&pre.type!==13){
-					allowed=type0;
-					asterick=empty;
-					inc(ptc,2).push(2);
-					str.push({value:Mexp.math.changeSign,type:0,pre:21,show:"-"});
-					str.push({value:"(",type:4,pre:0,show:"("});
+				else if(pre.type!==5&&pre.type!==7&&pre.type!==1&&pre.type!==3&&pre.type!==13){//changesign only when negative is found 
+					if(cToken==='-'){//do nothing for + token 
+									//don't add with the above if statement as that will run the else statement of parent if on Ctoken +
+						allowed=type0;
+						asterick=empty;
+						inc(ptc,2).push(2);
+						str.push({value:Mexp.math.changeSign,type:0,pre:21,show:"-"});
+						str.push({value:"(",type:4,pre:0,show:"("});
+					}
 				}
 				else{
 					str.push(obj);

package.json

@@ -1,6 +1,6 @@
 {
   "name": "math-expression-evaluator",
-  "version": "1.2.13",
+  "version": "1.2.14",
   "description": "A flexible math expression evaluator",
   "main": "src/formula_evaluator.js",
   "scripts": {

src/lexer.js

@@ -126,6 +126,7 @@ var indexOf = require('lodash.indexof');
 				throw(new Mexp.exception("Can't understand after "+inpStr.slice(i)));
 			}
 			var index=indexOf(token,key);
+			var cToken=key;
 			var cType=type[index];
 			var cEv=eva[index];
 			var cPre=preced[cType];
@@ -246,12 +247,15 @@ var indexOf = require('lodash.indexof');
 						inc(ptc,1);
 					}
 				}
-				else if(pre.type!==5&&pre.type!==7&&pre.type!==1&&pre.type!==3&&pre.type!==13){
-					allowed=type0;
-					asterick=empty;
-					inc(ptc,2).push(2);
-					str.push({value:Mexp.math.changeSign,type:0,pre:21,show:"-"});
-					str.push({value:"(",type:4,pre:0,show:"("});
+				else if(pre.type!==5&&pre.type!==7&&pre.type!==1&&pre.type!==3&&pre.type!==13){//changesign only when negative is found 
+					if(cToken==='-'){//do nothing for + token 
+									//don't add with the above if statement as that will run the else statement of parent if on Ctoken +
+						allowed=type0;
+						asterick=empty;
+						inc(ptc,2).push(2);
+						str.push({value:Mexp.math.changeSign,type:0,pre:21,show:"-"});
+						str.push({value:"(",type:4,pre:0,show:"("});
+					}
 				}
 				else{
 					str.push(obj);

test/index.js

@@ -113,4 +113,54 @@ describe('Testing Unit', function () {
   it('checks root function', function () {
 	 assert.equal(a.eval("root4"),"2");
   });
+  it('checks + precedence before number insise parenthesis ', function () {
+	 assert.equal(a.eval("(-2)"),"-2");
+  });
+  it('checks multiple allowable operator', function () {
+	 assert.equal(a.eval("2+++-++-+-+3"),"-1");
+	 assert.equal(a.eval("2*+3"),"6");
+  });
+});
+describe('These expression will raise error', function () {
+  it('should tell to compllete expression', function () {
+	try{
+		a.eval("2*")
+	}
+	catch(e){
+		assert.equal(e.message,"complete the expression")
+	}
+  });
+  it('should warn about multiple operators', function () {
+	try{
+		a.eval("2**3")
+	}
+	catch(e){
+		assert.equal(e.message,"* is not allowed after *")
+	}
+  });
+  it('should warn about multiple operators', function () {
+	try{
+		a.eval("2*Mod*3")
+	}
+	catch(e){
+		assert.equal(e.message,"Mod is not allowed after *")
+	}
+  });
+  it('should warn about operator inside parenthesis', function () {
+	try{
+		a.eval("(+)")
+	}
+	catch(e){
+		assert.equal(e.message,") is not allowed after +")
+	}
+  });
+  it('should warn about operator inside parenthesis', function () {
+	try{
+		a.eval("(+)")
+	}
+	catch(e){
+		assert.equal(e.message,") is not allowed after +")
+	}
+  });
+
 });