Missing Console Errors - File Not Found

[shiffman]

Starting over from #444, this github issue is to track error messages that show up in the native JS console, but not in the p5.js web editor console. To be clear, there are likely some error messages that should be hidden in the web editor console so this thread is also for discussion around these questions. This first issue contains a list of all the errors and subsequent comments will include specific code examples to trigger the missing error. Anyone should feel free to jump in and add to the comment thread and I'll keep the list below up to date!

• undefined values
• file not found errors with loadJSON(), loadImage(), etc.
• incorrect renderer, i.e. only available with webgl, etc.

Tagging @almchung as this relates to the Friendly Error System.

[shiffman]

Here's an example related to using an undefined string with text():

let txt;

function setup() { 
  createCanvas(400, 400);
  text(txt,100,100);
} 

JS console error: Cannot read property 'toString' of undefined

Another:

function setup() {
  let v;
  print(v);
}

Console should display: undefined

[shiffman]

Here's an example related to "file not found":

let img;

function preload() {
  img = loadImage('missingfile.png');	
}

function setup() {}

JS console error: GET http://alpha.editor.p5js.org//missingfile.png 404 (Not Found)

[shiffman]

Incorrect renderer:

function setup() { 
  createCanvas(400, 400);
} 

function draw() { 
  background(220);
  rotateZ(100);
}

Error should read: Uncaught not supported in p2d. Please use webgl mode

[catarak]

this has mostly been fixed, except for the file not found error. not sure why that's not getting to the console!

[GaurangTandon]

Is #868 a duplicate of this issue?

[catarak]

yep! they are the same issue.