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Merged
merged 6 commits into from
Oct 8, 2015
Merged

Refactored number parsing #27

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882b7dd
Refacrotored number parsing with parseFloat
Oct 7, 2015
5c181b7
Unit tests are passing after refactoring
Oct 7, 2015
9ad4f7e
Error handling just like the rest of the code
Oct 7, 2015
0323bbc
Overflow check
Oct 7, 2015
645897f
Overflow check, passing a string
Oct 7, 2015
5245aa6
Added few tests for the long numbers and improved the check
Oct 8, 2015
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190 changes: 46 additions & 144 deletions jsonparse.js
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Original file line number Diff line number Diff line change
Expand Up @@ -27,13 +27,7 @@ var NULL1 = C.NULL1 = 0x41;
var NULL2 = C.NULL2 = 0x42;
var NULL3 = C.NULL3 = 0x43;
var NUMBER1 = C.NUMBER1 = 0x51;
var NUMBER2 = C.NUMBER2 = 0x52;
var NUMBER3 = C.NUMBER3 = 0x53;
var NUMBER4 = C.NUMBER4 = 0x54;
var NUMBER5 = C.NUMBER5 = 0x55;
var NUMBER6 = C.NUMBER6 = 0x56;
var NUMBER7 = C.NUMBER7 = 0x57;
var NUMBER8 = C.NUMBER8 = 0x58;
var STRING1 = C.STRING1 = 0x61;
var STRING2 = C.STRING2 = 0x62;
var STRING3 = C.STRING3 = 0x63;
Expand All @@ -55,14 +49,6 @@ function Parser() {
this.string = undefined; // string data
this.unicode = undefined; // unicode escapes

// For number parsing
this.negative = undefined;
this.magnatude = undefined;
this.position = undefined;
this.exponent = undefined;
this.negativeExponent = undefined;
this.numberLength = 0;

this.key = undefined;
this.mode = undefined;
this.stack = [];
Expand All @@ -83,7 +69,7 @@ Parser.toknam = function (code) {
if (C[key] === code) { return key; }
}
return code && ("0x" + code.toString(16));
}
};

var proto = Parser.prototype;
proto.onError = function (err) { throw err; };
Expand All @@ -108,15 +94,14 @@ proto.write = function (buffer) {
}else if(n === 0x66){ this.tState = FALSE1; // f
}else if(n === 0x6e){ this.tState = NULL1; // n
}else if(n === 0x22){ this.string = ""; this.tState = STRING1; // "
}else if(n === 0x2d){ this.negative = true; this.tState = NUMBER1; // -
}else if(n === 0x30){ this.magnatude = 0; this.tState = NUMBER2; // 0
}else if(n === 0x2d){ this.string = "-"; this.tState = NUMBER1; // -
}else{
if (n > 0x30 && n < 0x40) { // 1-9
this.magnatude = n - 0x30; this.tState = NUMBER3;
if (n >= 0x30 && n < 0x40) { // 1-9
this.string = String.fromCharCode(n); this.tState = NUMBER3;
} else if (n === 0x20 || n === 0x09 || n === 0x0a || n === 0x0d) {
// whitespace
} else {
return this.charError(buffer, i);
return this.charError(buffer, i);
}
}
}else if (this.tState === STRING1){ // After open quote
Expand Down Expand Up @@ -180,131 +165,48 @@ proto.write = function (buffer) {
} else {
return this.charError(buffer, i);
}
}else if (this.tState === NUMBER1){ // after minus
n = buffer[i];
this.numberLength++;
if (n === 0x30) { this.magnatude = 0; this.tState = NUMBER2; }
else if (n > 0x30 && n < 0x40) { this.magnatude = n - 0x30; this.tState = NUMBER3; }
else {
return this.charError(buffer, i);
}
}else if (this.tState === NUMBER2){ // * After initial zero
n = buffer[i];
this.numberLength++;
if(n === 0x2e){ // .
this.position = 0.1; this.tState = NUMBER4;
}else if(n === 0x65 || n === 0x45){ // e/E
this.exponent = 0; this.tState = NUMBER6;
}else{
this.tState = START;
this.onToken(NUMBER, 0);
this.offset += this.numberLength - 1;
this.numberLength = 0;
this.magnatude = undefined;
this.negative = undefined;
i--;
}
}else if (this.tState === NUMBER3){ // * After digit (before period)
n = buffer[i];
this.numberLength++;
if(n === 0x2e){ // .
this.position = 0.1; this.tState = NUMBER4;
}else if(n === 0x65 || n === 0x45){ // e/E
this.exponent = 0; this.tState = NUMBER6;
}else{
if (n >= 0x30 && n < 0x40) { this.magnatude = this.magnatude * 10 + n - 0x30; }
else {
this.tState = START;
if (this.negative) {
this.magnatude = -this.magnatude;
this.negative = undefined;
}
this.onToken(NUMBER, this.magnatude);
this.offset += this.numberLength - 1;
this.numberLength = 0;
this.magnatude = undefined;
i--;
}
}
}else if (this.tState === NUMBER4){ // After period
n = buffer[i];
this.numberLength++;
if (n >= 0x30 && n < 0x40) { // 0-9
this.magnatude += this.position * (n - 0x30);
this.position /= 10;
this.tState = NUMBER5;
} else {
return this.charError(buffer, i);
}
}else if (this.tState === NUMBER5){ // * After digit (after period)
n = buffer[i];
this.numberLength++;
if (n >= 0x30 && n < 0x40) { // 0-9
this.magnatude += this.position * (n - 0x30);
this.position /= 10;
}
else if (n === 0x65 || n === 0x45) { this.exponent = 0; this.tState = NUMBER6; } // E/e
else {
this.tState = START;
if (this.negative) {
this.magnatude = -this.magnatude;
this.negative = undefined;
}
this.onToken(NUMBER, this.negative ? -this.magnatude : this.magnatude);
this.offset += this.numberLength - 1;
this.numberLength = 0;
this.magnatude = undefined;
this.position = undefined;
i--;
}
}else if (this.tState === NUMBER6){ // After E
n = buffer[i];
this.numberLength++;
if (n === 0x2b || n === 0x2d) { // +/-
if (n === 0x2d) { this.negativeExponent = true; }
this.tState = NUMBER7;
}
else if (n >= 0x30 && n < 0x40) {
this.exponent = this.exponent * 10 + (n - 0x30);
this.tState = NUMBER8;
}
else {
return this.charError(buffer, i);
}
}else if (this.tState === NUMBER7){ // After +/-
n = buffer[i];
this.numberLength++;
if (n >= 0x30 && n < 0x40) { // 0-9
this.exponent = this.exponent * 10 + (n - 0x30);
this.tState = NUMBER8;
}
else {
return this.charError(buffer, i);
}
}else if (this.tState === NUMBER8){ // * After digit (after +/-)
n = buffer[i];
this.numberLength++;
if (n >= 0x30 && n < 0x40) { // 0-9
this.exponent = this.exponent * 10 + (n - 0x30);
}
else {
if (this.negativeExponent) {
this.exponent = -this.exponent;
this.negativeExponent = undefined;
}
this.magnatude *= Math.pow(10, this.exponent);
this.exponent = undefined;
if (this.negative) {
this.magnatude = -this.magnatude;
this.negative = undefined;
} else if (this.tState === NUMBER1 || this.tState === NUMBER3) {
n = buffer[i];

switch (n) {
case 0x30: // 0
case 0x31: // 1
case 0x32: // 2
case 0x33: // 3
case 0x34: // 4
case 0x35: // 5
case 0x36: // 6
case 0x37: // 7
case 0x38: // 8
case 0x39: // 9
case 0x2e: // .
case 0x65: // e
case 0x45: // E
case 0x2b: // +
case 0x2d: // -
this.string += String.fromCharCode(n);
this.tState = NUMBER3;
break;
default:
this.tState = START;
var result = Number(this.string);

if (isNaN(result)){
return this.charError(buffer, i);
}

if ((this.string.match(/[0-9]+/) == this.string) && (result.toString() != this.string)) {
// Long string of digits which is an ID string and not valid and/or safe JavaScript integer Number
this.onToken(STRING, this.string);
} else {
this.onToken(NUMBER, result);
}

this.offset += this.string.length - 1;
this.string = undefined;
i--;
break;
}
this.tState = START;
this.onToken(NUMBER, this.magnatude);
this.offset += this.numberLength - 1;
this.numberLength = 0;
this.magnatude = undefined;
i--;
}
}else if (this.tState === TRUE1){ // r
if (buffer[i] === 0x72) { this.tState = TRUE2; }
else { return this.charError(buffer, i); }
Expand Down
9 changes: 6 additions & 3 deletions test/primitives.js
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Original file line number Diff line number Diff line change
Expand Up @@ -23,12 +23,14 @@ var expected = [
[ [], [ -1 ] ],
[ [ 0 ], -0.1 ],
[ [], [ -0.1 ] ],
[ [ 0 ], 6.019999999999999e+23 ],
[ [], [ 6.019999999999999e+23 ] ]
[ [ 0 ], 6.02e+23 ],
[ [], [ 6.02e+23 ] ],
[ [ 0 ], '7161093205057351174' ],
[ [], [ '7161093205057351174'] ]
];

test('primitives', function (t) {
t.plan(23);
t.plan(25);

var p = new Parser();
p.onValue = function (value) {
Expand All @@ -51,4 +53,5 @@ test('primitives', function (t) {
p.write('[0,1,-1]');
p.write('[1.0,1.1,-1.1,-1.0][-1][-0.1]');
p.write('[6.02e23]');
p.write('[7161093205057351174]');
});