Spell check for source editor, notebooks, etc.

[jmcphers]

VS Code doesn't have any global spell checking service, and does not have built-in spell checking for most of its components. This is a long-standing issue that has created a lot of third-party spelling plugins.

Because we want Positron to have a pleasant scientific authoring experience out of the box, without installing plugins, we should bundle a spellcheck extension, or add a spellcheck service as part of the core or editor system.

Some notes on existing art:

• The most popular extension for spell checking appears to be Code Spell Checker, with about 8M installs.
• Quarto has spell checking in its visual editor (only), which appears to be powered by typo.js. This all happens in extension-land and doesn't use anything from the VS Code core. If we create a spelling service ourselves, we could possibly expose it via the extension API and use it in the Quarto extension instead of typo.js. We'd probably want to so that spellcheck is consistent across visual and source mode. https://github.com/quarto-dev/quarto/blob/d7f5af236777be4d1ca7b7165c3df847be8faa84/packages/editor-ui/package.json#L20
• VS Code has a long-standing issue to support an offline spelling mode. Offline spell checker for VSCode microsoft/vscode#20266
• Electron has support for hooking into the system spelling APIs, which might be really nice since they will respect user preferences defined outside Positron and have good-quality dictionaries for many languages. However, we can't rely on these for the server version of Positron, so this can't be our only story for spell checking. https://www.electronjs.org/docs/latest/tutorial/spellchecker

I generally think it would be preferable to build our own spell check service as opposed to depending on a third party plugin.

Here's spellcheck working against a visual mode doc with Quarto:

[EmilHvitfeldt]

It would be nice if it also worked in the various chunk options like fig-cap and fig-alt

[chendaniely]

is it possible to make the spell check fix suggestions show up on right-click?
it's one of the biggest annoyances I have with all the spell checkers is hovering over and clicking the right thing. sometimes the window disappers on me before I can click on the suggestions box in regular vscode

[chendaniely]

If we do have a spell checker that ships with positron, we might want to also curate a list of words for a custom dictonary too.

e.g., tabset for quarto ::: {.panel-tabset}

not sure if there's a better place to put in words for custom dictonary things.

[jmcphers]

We already have such a list, curated for RStudio:

https://github.com/rstudio/rstudio/blob/main/src/gwt/src/org/rstudio/studio/client/common/spelling/domain_specific_words.csv

Although for your specific example, I think that it'd be better for us just to recognize ::: as a fence line that doesn't need spell checking.

[thomasp85]

Also, spell checking in roxygen comments (maybe comments in general) - I'm sure it is on the radar and part of the general spell-checking effort, so just adding it here for completion

[jmcphers]

Unsurprisingly, this has already been requested by a beta user: https://github.com/posit-dev/positron-beta/issues/121