Injection grammars with embeddedLanguages

[mjbvz]

Problem
I'm trying to write an injection for css grammar into JS/TS template strings. The following injection works, the embeddedLanguages property does not seem to be observed for injections

    "grammars": [
      {
        "scopeName": "meta.embedded.css",
        "path": "./syntaxes/injection.json",
        "injectTo": [
          "source.js",
          "source.jsx",
          "source.ts",
          "source.tsx"
        ],
        "embeddedLanguages": {
          "meta.embedded.css": "css"
        }
      }
    ]

[mjbvz]

To verify, try creating a new injection grammar such as:

{
	"fileTypes": [],
	"injectionSelector": "L:markup.fenced_code.block.markdown",
	"patterns": [
		{
			"include": "#superjs-code-block"
		}
	],
	"repository": {
		"superjs-code-block": {
			"begin": "superjs",
			"end": "(^|\\G)(?=\\s*[`~]{3,}\\s*$)",
			"patterns": [
				{
					"include": "source.js"
				}
			]
		}
	},
	"scopeName": "markdown.superjs.codeblock"
}

with contributes:

{
        "scopeName": "markdown.superjs.codeblock",
        "path": "./syntaxes/test.json",
        "injectTo": [
          "text.html.markdown"
        ]
      }

This will highlight:

```superjs
1 + 1
```

blocks in markdown. Try adding embeddedLanguages and confirm that the content of the code block are the correct language

[alexdima]

@mjbvz The best is to reach out to @aeschli . he implemented all the injection stuff in vscode-textmate.