Using `JSON.stringify()` falsely triggers `scalar list token string in a scalar string context` error

[ansgarm]

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cdktf & Language Versions

0.10.4

Affected Resource(s)

Debug Output

Expected Behavior

Should work if possible or print a more useful warning (e.g. recommend Fn.jsonencode()).

Actual Behavior

Fails with

Error: Found an encoded list token string in a scalar string context. Use 'Fn.element(list, 0)' (not 'list[0]') to extract elements from token lists

Steps to Reproduce

const arr = ["a", "b", "c"];
const jsonString = JSON.stringify({
  "test:key": Fn.concat([arr, arr]),
});
new TerraformLocal(this, "fails", jsonString);

Important Factoids

Using Fn.jsonencode() works as a workaround.

References

[DanielMSchmidt]

I think it should print a better error message, but it should not work. The token could have any value and the serialization to JSON happens with the token as a string, so there could potentially be extra things rendered at execution time that don't match what a user would expect. But yeah we should try to make the error message clearer