For…in loop in GLTFParser can cause gltf model load to fail

Description of the problem

GLTFParser.prototype.loadMeshes and GLTFParser.prototype.loadNodes use for...in loops.

Since a for...in loop in JavaScript iterates over an objects properties, these can cause the parse to fail if there is a custom property added to the Array object elsewhere on the site. For example, in GLTFParser.prototype.loadMeshes there is:

for ( var name in primitives ) {
    var primitive = primitives[ name ];
    var geometry = geometries[ name ];

If another script does something like:

Array.prototype.newCustomProp = function (num) {
}

Then eventually name would equal newCustomProp and the attempt to find primitive/geometry will fail.

Three.js version

• Dev
• r87
• …

Browser

• All of them
• Chrome
• Firefox
• Internet Explorer

OS

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• Windows
• macOS
• Linux
• Android
• iOS