devtools: Apply attribute modifications in the inspector to the DOM tree#42601
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| #[serde(rename = "newValue")] | ||
| new_value: Option<String>, | ||
| }, | ||
| } |
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This enum may seem a bit redundant. I have a followup to this PR where more variants are added.
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🔨 Triggering try run (#21994097619) for Linux (WPT) |
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Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
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Test results for linux-wpt from try job (#21994097619): Flaky unexpected result (26)
Stable unexpected results that are known to be intermittent (21)
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I'm pinging you two because you reviewed my previous devtools PRs and there are not many maintainers familiar with this area of the code. Feel free to tell me if you dont want to be pinged on future PRs ^^ |
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Looks nice! And feel free to ping me for devtools code :)
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Thank you for adding tests, love it :)
Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
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Currently, `script` and `devtools` use a node's unique id to identify it across requests. The unique ID is part of a node's rare data field and is really only meant for debugging. Instantiating it on a node causes it's memory usage to go up significantly. Now, when the devtools ask for information about a specific `Node` then they send the unique ID to `script`, and the script thread then walks the whole DOM tree searching for that specific ID. This happens here: https://github.com/servo/servo/blob/6d0b65121852e75ad9aea5cdf3f04ca186cc67f9/components/script/devtools.rs#L142-L153 So, in the worst case, all of the nodes in the tree now have a unique ID. That's not great! Also, when `script` notifies `devtools` about changes to a DOM node then `devtools` expects a `NodeActor` to exist for that Node. The actor might not exist if the inspector doesn't know about that node yet - that happens when the user hasn't expanded their parent yet. That is an oversight from #42601 and causes problems now(#42784) because for the longest time, `devtools` was mostly the one sending requests. Of course, we could make `devtools` simply ignore updates for nodes that it doesn't know about, but ideally we shouldn't send these updates in the first place. This change implements a lookup map on the `ScriptThread` that contains all nodes that have been sent to the devtools inspector. The map allows us to efficiently resolve a unique ID to a `Node` in O(1), without creating unique IDs for the whole tree. It also allows us to only send DOM updates for nodes that the inspector cares about. For now, entries from the cache are not evicted unless the relevant pipeline is closed. That reflects reality, because the inspector also keeps using them forever. In the future we will tell the inspector when nodes are removed from the tree - then it can't interact with them anymore, and we can remove them from the script-side map. This is change is not all that complicated but it involves moving a lot of code around, so feel free to ask for clarification when something is unclear! Testing: This change adds a test Fixes part of #42784 --------- Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
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Currently, `script` and `devtools` use a node's unique id to identify it across requests. The unique ID is part of a node's rare data field and is really only meant for debugging. Instantiating it on a node causes it's memory usage to go up significantly. Now, when the devtools ask for information about a specific `Node` then they send the unique ID to `script`, and the script thread then walks the whole DOM tree searching for that specific ID. This happens here: https://github.com/servo/servo/blob/6d0b65121852e75ad9aea5cdf3f04ca186cc67f9/components/script/devtools.rs#L142-L153 So, in the worst case, all of the nodes in the tree now have a unique ID. That's not great! Also, when `script` notifies `devtools` about changes to a DOM node then `devtools` expects a `NodeActor` to exist for that Node. The actor might not exist if the inspector doesn't know about that node yet - that happens when the user hasn't expanded their parent yet. That is an oversight from servo#42601 and causes problems now(servo#42784) because for the longest time, `devtools` was mostly the one sending requests. Of course, we could make `devtools` simply ignore updates for nodes that it doesn't know about, but ideally we shouldn't send these updates in the first place. This change implements a lookup map on the `ScriptThread` that contains all nodes that have been sent to the devtools inspector. The map allows us to efficiently resolve a unique ID to a `Node` in O(1), without creating unique IDs for the whole tree. It also allows us to only send DOM updates for nodes that the inspector cares about. For now, entries from the cache are not evicted unless the relevant pipeline is closed. That reflects reality, because the inspector also keeps using them forever. In the future we will tell the inspector when nodes are removed from the tree - then it can't interact with them anymore, and we can remove them from the script-side map. This is change is not all that complicated but it involves moving a lot of code around, so feel free to ask for clarification when something is unclear! Testing: This change adds a test Fixes part of servo#42784 --------- Signed-off-by: Simon Wülker <simon.wuelker@arcor.de>
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The inspector view allows modifying the attributes of DOM elements. However, we lie to the devtools client: While it looks like the attributes change, the changes are never actually applied to the DOM.
This change fixes that, and also makes it so attribute modifications from non-inspector sources are shown in the inspector.
Testing: This change adds two tests