File path in AST locations different between --data and --bundle loaded files

[tsandall]

Simple example:

x.rego:

package x

p { not a }   # a is unsafe

Output differs depending on whether -b or -d is used:

torin:~/temp$ opa eval -d $PWD 'data'
{
  "errors": [
    {
      "message": "var a is unsafe",
      "type": "ast",
      "code": "rego_unsafe_var_error",
      "location": {
        "file": "/home/torin/temp/x.rego",
        "row": 3,
        "col": 9
      }
    }
  ]
}
torin:~/temp$ opa eval -b $PWD 'data'
{
  "errors": [
    {
      "message": "var a is unsafe",
      "type": "ast",
      "code": "rego_unsafe_var_error",
      "location": {
        "file": "/x.rego",
        "row": 3,
        "col": 9
      }
    }
  ]
}

Inside of the VS code extension this makes a difference because the file paths for -d option are clickable whereas the file paths for -b are not.

For -b files loaded out of a directory (i.e., not out of a tarball), I think it would be better to prefix with the -b flag value. For the tarball case, it's a bit trickier.