Activate embedded languages for indent rules

[roblourens]

From #98181 (comment)

PHP defines HTML as an embedded language here: https://github.com/microsoft/vscode/blob/master/extensions/php/package.json#L44. The bug is that VSCode doesn't activate 'html' when it needs it's indent rules. As HTML defines the indent rules in code, activation is necessary.

It's a VSCode issue. I suggest to create a new issue and assign it to @alexdima.

[alexdima]

Currently, the onLanguage activation event fires only when a file that resolves to a certain language gets opened -- https://code.visualstudio.com/api/references/activation-events#onLanguage -- and not when encountering an embedded language as part of tokenization.

I am not 100% convinced we should activate all embedded languages. e.g. Is it expected to activate java when writing markdown and using fenced code blocks?

If the experience of php is so dependent on html, shouldn't the php extension take a dependency on the html extension?

FYI @aeschli

[roblourens]

via extensionDependencies? Could also do that. But it makes sense to me that if I want to add rules for the 'foo' language, then I always get activated when those rules would be applied to a region in some file.

[alexdima]

Currently, the language-configuration.json is read when encountering an embedded language. This is done here. But I think this must be something that the html extension does via API and not via the language-configuration.json? We want at one point to move also the onEnter rules to the language-configuration.json, perhaps that's what's missing here?

[roblourens]

Yeah, the html extension uses vscode.languages.setLanguageConfiguration with onEnterRules, wordPattern, and indentationRules.

[andrestone]

Hi!

Is there any workaround for this?

I have an autocompletion extension that works with onLanguage activation and I'd like to have it working when the language is used as embeddedLanguage.

Thanks.

[alexdima]

Since we now support defining regular expression in language-configuration.json files, we could simply move the setLanguageConfiguration calls to the JSON files.