VS Code: How to convert snippet placeholder to uppercase or lowercase?

Question

In VS Code, the docs for creating user defined snippets mentions some Grammar which includes options for /upcase, /downcase, and /capitalize

Answer 1

For reference:

The integer in the EBNF docs refers to a RegExp group not to a tabstop reference so should work:

"test": {
    "prefix": "test",
    "body": "${1} -> ${1/(Asdf)/${1:/upcase}/} ${1/(Asdf)/${1:/downcase}/}"
}