The problem is generally due to the use of `var`, this one
https://github.com/odoo-dev/odoo/blob/58a046d2146e884d467cde827f89fa603ed98a3b/addons/web/static/src/js/views/basic/basic_model.js#L1780 followed by an asynchronous call to a function using it
We can therefore summarize the part of the `_applyOnChange` function
that interests us by
```js
for () {
if (field. type === 'one2many' || field. type === 'many2many') {
var list;
...
//using list
...
promiseFunction(list).then(function(){
//using list
})
}
}
```
In the case where we have two one2many which follow each other,
this scenario occurs:
- `list` is initially the first o2m
- the `promiseFunction` is called with `list` (first o2m)
- before the promise is resolved the loop continues
- `list` is `Promise.then()` the second o2m
- the first call to `promiseFunction` with `list` (first o2m) is done
- we enter in `Promise.then()`
- `list` is currently worth the value of the second o2m because
`list` is a `var`
- the second call to `promiseFunction` with `list` is finished
- we enter the `Promise.then()`
- `list` is currently worth the value of the second o2m because
`list` is a `var`
Result: `Promise.then()` is called twice with the first o2m and never
with the second
We can see what happened with this code example:
```js
const array = ["a", "b"];
const asyncRead = async(value) => {
console.log("async function arg", value)
setTimeout(()=>{
return Promise. resolve(value);
}, 100)
}
const forFunction = () => {
for (let i = 0; i < array.length; i++){
var list = array[i];
asyncRead(list).then(function (){
console.log("then async function arg", list)
})
}
}
forFunction()
/*
async function arg a
async function arg b
then async function arg b
then async function arg b
*/
```
While if:
We use `let`
by replacing `var list = array[i];` with `let list = array[i];`
OR
We force the use of `Promise.resolve()` argument
by replacing `.then(function (){}` with `.then(function (list){}`
We will get:
```js
/*
async function arg a
async function arg b
then async function arg a
then async function arg b
*/
```
opw-2694855
closesodoo/odoo#89160
X-original-commit: 99cb2f52e109ccf94ac8bd735cd776e84ef04260
Signed-off-by: Nicolas Lempereur (nle) <nle@odoo.com>
Lucas Perais (lpe)
6af8b7f95e