1853124 - Avoid uncessary CodeMirror updates

Status: RESOLVED FIXED

(DevTools :: Debugger, enhancement)

Description

[Alexandre Poirot [:ochameau]]

Bug 1775200 started avoiding a few CodeMirror updates, but we still have a few superfluous ones.

Some of these unecessary updates relate to bug 1853123.
But there is also some uncessary changes related to selectedSourceTextContent attribute which changes between undefined, promise with null value and promise with an actual value.

Comment 1

[Alexandre Poirot [:ochameau]]

Attachment: Bug 1853124 - [devtools] Avoid uncessary CodeMirror updates.

We were trying to update CodeMirror text and scroll position too frequently.
These calls can be expensive on large documents.

Comment 2

[Alexandre Poirot [:ochameau]]

Attachment: Bug 1853124 - [devtools] Avoid changing cursor location when scrolling to first character.

For some reason, the previous changeset triggers an additional call to scrollToColumn
during open-large-minified-file DAMP test, only on try but not locally.

Calling codeMirror.charCoords can be slow on large files and we often
try to scroll to the first line/first column. Let's arbitrarily scroll
to top/left when this simple case happens.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/14272e0686b3
[devtools] Avoid uncessary CodeMirror updates. r=devtools-reviewers,bomsy
https://hg.mozilla.org/integration/autoland/rev/0fad6751508b
[devtools] Avoid changing cursor location when scrolling to first character. r=devtools-reviewers,bomsy

Comment 4

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/14272e0686b3
https://hg.mozilla.org/mozilla-central/rev/0fad6751508b