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[p5.js 2.0+ Bug Report]: storeItem() validation branches are missing `return`, so bad input throws a TypeError or is stored anyway

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#9,242 0 comentarios 0 reacciones 0 asignados Ver en GitHub

Los mantenedores suelen responder en 3 días

@iUjjwalRaj ya está trabajando en esto.

Desde el 6/10/2026.

  • #9250 de @iUjjwalRaj — abierto

Evaluación

Dificultad
1/5
Tiempo estimado
Menos de una hora
Aptitud para principiantes
85/100
Tipo de issue
Error
Claridad
Bien especificado
Estado de actividad
Activo
Stack tecnológico
javascript
Área
data

Línea de trabajo

Comienza en src/data/local_storage.js: storeItem() alrededor de la línea 114 y removeItem() alrededor de la línea 424, donde las tres ramas de validación informan a través de p5._friendlyError y luego continúan. Reproduce con el snippet del issue: storeItem(42, 'hello') debería informar y detenerse en lugar de lanzar TypeError: key.endsWith is not a function, y storeItem('k', undefined) debería dejar getItem('k') vacío en lugar de devolver la cadena "undefined". Hecho significa que cada rama retorna antes de cualquier llamada a localStorage, con tests que cubran ambos casos; el try/catch propuesto alrededor de las dos llamadas a setItem es un seguimiento separable.

Escrito por el modelo de indexación a partir del texto del issue.

Descripción

Most appropriate sub-area of p5.js?
  • Data
p5.js version

2.3.2 (verified on main @ 94fb07d)

Web browser and version

All

Operating system

All

Steps to reproduce this
Steps:
  1. Run the sketch below.
  2. storeItem(42, 'hello') prints the friendly error about the key not being a string, then throws TypeError: key.endsWith is not a function and halts the sketch.
  3. Comment that line out. storeItem('k', undefined) prints "You cannot store undefined variables using storeItem()" — and then stores it anyway.
  4. getItem('k') returns the string "undefined".
Snippet:
function setup() {
  storeItem(42, 'hello');        // friendly error, then an uncaught TypeError

  storeItem('k', undefined);     // "You cannot store undefined variables..."
  print(getItem('k'));           // "undefined"
  print(typeof getItem('k'));    // "string"
}

Cause

None of the three validation branches in storeItem() returns after reporting the error, so execution falls through into code that assumed the input was already valid:

// src/data/local_storage.js:114
fn.storeItem = function (key, value) {
  if (typeof key !== 'string') {
    p5._friendlyError(
      `The argument that you passed to storeItem() - ${key} is not a string.`,
      'storeItem'
    );
  }                                  // <- no return
  if (key.endsWith('p5TypeID')) {    // <- throws when key is a number
    p5._friendlyError(...);
  }                                  // <- no return

  if (typeof value === 'undefined') {
    p5._friendlyError(
      'You cannot store undefined variables using storeItem().',
      'storeItem'
    );
  }                                  // <- no return

  let type = typeof value;
  switch (type) { /* ... 'undefined' hits `default`, unchanged ... */ }

  localStorage.setItem(key, value);              // stores "undefined"
  localStorage.setItem(`${key}p5TypeID`, type);  // stores type "undefined"
};

So the non-string-key case produces a friendly error immediately followed by a hard TypeError from the next check, and the undefined-value case produces a message that is simply not true about what happened — the value is written to localStorage, tagged with type "undefined", and handed back by getItem() as a string.

fn.removeItem (src/data/local_storage.js:424) has the same shape: it reports a non-string key and then calls localStorage.removeItem(key) regardless.

Expected behaviour

Reporting an invalid argument should stop the operation. Nothing should be written, nothing downstream should see input it cannot handle, and the message should describe what actually happened.

Suggested fix

Add return; to each validation branch in storeItem() and removeItem():

   if (typeof key !== 'string') {
     p5._friendlyError(
       `The argument that you passed to storeItem() - ${key} is not a string.`,
       'storeItem'
     );
+    return;
   }

…and likewise for the p5TypeID suffix check and the undefined value check.

One related thing, if you want it in the same PR

The two localStorage.setItem calls are unguarded. They throw QuotaExceededError when storage is full and SecurityError where site data is blocked (Safari private browsing, or a sketch embedded in a third-party iframe with cookies restricted) — both of which surface as uncaught exceptions that stop the sketch rather than as friendly errors.

There is also a consistency hazard: if the first setItem succeeds and the second one fails, the value is stored without its p5TypeID tag, and getItem() then returns it as an untyped raw string. Wrapping both calls in a single try/catch that reports through p5._friendlyError would make that legible and keep the pair atomic. Happy to split this out into its own issue if you'd rather keep them separate.

I'd be glad to open a PR for the missing returns with tests for both cases.

Lenguaje dominante
JavaScript
Estrellas
24.1k
Forks
3.9k
Merge medio
2 d 20 h
PR fusionados (30 d)
37

Preparar el entorno

Primeros pasos

  1. Lee el issue completo y luego la guía de contribución del proyecto.
  2. Comenta en el issue que vas a ocuparte — evita que dos personas hagan lo mismo.
  3. Haz un fork del repositorio y trabaja en una rama.
  4. Abre un pull request que haga referencia al número del issue.

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