In some cases "rules" can parse with dots/hyphens/etc in name

[patrick-east]

Expected Behavior

A rule defined like:

package example

foo.bar = x {
    x := 123
}

Should raise a parse error. This isn't a valid rule name.. Same goes for..

package example

foo-bar = x {
    x := 123
}

And some others (can toss in + and more in there)

Actual Behavior

The "rule" parses... but isn't what the author probably intended. What you get is:

$ opa eval -d /tmp/x.rego -f pretty 'data'
{
  "example": {
    "foo": {
      "bar": 123
    },
    "x": 123
  }
}

😞

Additional Info

Whats happening is that it is being parsed with a partial rule like foo[bar] = x { true } and a rule defined with wrapping braces (see #2199) of x = 123 { true }.

{
  "package": {
    "path": [
      {
        "type": "var",
        "value": "data"
      },
      {
        "type": "string",
        "value": "example"
      }
    ]
  },
  "rules": [
    {
      "head": {
        "name": "foo",
        "key": {
          "type": "string",
          "value": "bar"
        },
        "value": {
          "type": "var",
          "value": "x"
        }
      },
      "body": [
        {
          "index": 0,
          "terms": {
            "type": "boolean",
            "value": true
          }
        }
      ]
    },
    {
      "head": {
        "name": "x",
        "value": {
          "type": "number",
          "value": 123
        },
        "assign": true
      },
      "body": [
        {
          "index": 0,
          "terms": {
            "type": "boolean",
            "value": true
          }
        }
      ]
    }
  ]
}