This commit is a significant refactoring of the internal of QWeb. It
simplifies the way variables/scoping and slots interact together. The
main idea is that we use a simple scope object instead of a
context/var/scope object.
This commit also implement the actual correct QWeb semantic for the
t-call directive with a sub body. Before, we simply extracted the
variables from the body and injected them at the top of the sub
template. We now simply compile the body before the sub template.
This is a joint work with Lucas (lpe).
closes#541closes#544closes#545closes#557closes#556
This is a really interesting problem: there was a situation where a
component would not have an event handler properly bound. The reason was
that we were in a situation where the scheduler task queue was flushed
at an unfortunate timing:
- parent component template is rendered
- subcomponent is prepared:
- sub component is willStarted
- it is rendered (so, fiber counter is set to 0)
- scheduler task queue is flushed => we patch the DOM
- the code registered in the __prepare.then(handler) is executed, which
add the createHook to the vnode (but after the dom is patched)
Usually, the last two steps happen in a different order, but in an
environment with connected components, we sometimes flush the task queue
at various moments, so some code could be executed between the end of
__prepare and the registered handler.
The fix is interesting: we give a callback to the __prepare function
instead of registering a .then handler to the deferred. This callback
is then guaranteed to be called at exactly the proper timing.
Thanks seb for the hard work of finding the root cause of this issue
closes#520
Following 2922cee6ea
Previous commit was not correct: used children with a cancelled
fiber (for instance, with a new currentFiber) could be destroyed.
This commit fixes the issue differently, by directly detecting
children that are not used anymore (and not mounted), and destroy
them directly (no need to wait for willStart promise to be resolved
anymore).
We don't see any usecase for it, it makes the code more complex,
and there were still potential unresolved concurrency issues with
it.
Part of task #295
With this commit, we can now do this:
const SUBTEMPLATE = xml`<span><t t-esc="state.n"/></span>`
class Parent extends Widget {
static template = xml`<div><t t-call="${SUBTEMPLATE}"/></div>`
state = {n: 42};
}
Big change! This commit introduces an xml function tag to easily define
inline templates.
This is a pretty big change toward single file owl components
Part of #284
Of course, the templateId computation is kind of tricky. Here, an issue
occurred because the templateId did not take the componentId into
account when we were in a loop, but with no keyed parent.
This meant that multiple sub components shared the same templateId,
confusing the vdom algorithm.
This is a difficult part of owl: we need to be able to reconcile the
vdom generated (this is done with our virtual dom algorithm), but also
to be able to reconcile the proper components.
The issue here is that when we are in a list, with a t-key attribute on all
list nodes, and those list nodes contains sub component, then the
component system used the index of the list, and did not take into
account the key from the parent. The fix is to keep track of the
current key in the context, and uses that as a part of the templateId.
Géry Debongnie