Currently, the `moveBefore` method on VNodes assumes that the `other`
VNode it receives is of the same type, and that the entire VNode tree
below that other VNode has the exact same structure. While this is
correct in most cases, it breaks down when there is a VToggler somewhere
in the VNode tree, as the structure below a VToggler can be very
different from the structure below another VToggler that was created
from the same compiled code. For example, two iterations of a t-foreach
that contains a <t t-component="..."/> may spawn different components,
and different components obviously have different structures.
One way to fix this is to remove the assumption that the structure of
the `this` block tree in moveBefore is the same as the structure
of the `other` block tree, and instead, always give the concrete DOM
node before which we want to move the current VNode instead of giving it
a VNode and an afterNode as a fallback. One problem with this solution
is that it degrades performance in the "standard" case, where a
t-foreach contains no VToggler anywhere in its block tree, as retrieving
the first concrete DOM node requires calling firstNode() which
recursively traverses the entire tree.
To avoid this performance penalty in the standard case, we opt to only
go down this route whenever we encounter a VToggler when calling
`moveBefore`. This requires that we maintain two separate methods, one
to move a VNode before another VNode of assumed similar structure, which
is basically the current implementation of `moveBefore` for all VNode
types except VToggler, and one implementation that moves a VNode before
a concrete DOM node. This method needs to be implemented for all VNode
types, as all VNode types can be descendants of a VToggler. This method
will only be called from one place: the `moveBeforeVNode` method of the
toggler, which is the point where we realize that the assumption of
identical structure breaks down.
Co-authored-by: Bruno Boi <boi@odoo.com>
When creating the template node for a block, we create htmlelements and
set their (static) attributes. But this can have side effects. For
example, setting the src attribute for an img element will trigger a
request to fetch the image.
We avoid that issue by simply setting the html element template node
inside a <template/> element.
Note that I don't really see how to test this fix in jest: we don't have
a real browser, and no real way to check for this side effect.
closes#1257
This commit makes all errors thrown in owl use a custom error class. The
main point of this is to always wrap user-code errors that happen during
the owl lifecycle so that they can be treated uniformly in onError by
checking the cause property, and also allows user code to differenciate
owl errors from non-owl errors reliably at runtime.
Samuel Degueldre