vscode-extension-samples/contentprovider-sample/locations-syntax.json

{
	"name": "Locations",
	"scopeName": "source.locations",
	"patterns": [
		{
			"name": "comment.line.file",
			"match": "file:.*$"
		},
		{
			"name": "keyword.locations",
			"match": "  \\d+:"
		},
		{
			"name": "keyword.control.locations",
			"match": "  \\d+"
		}
	]
}