Function calls through imported packages fail with "could not find function"

[andrioni]

Hi, it seems like functions cannot be called through package imports — only variable refs resolve through imports (related: #541, #284), see the example below:

package lib

import rego.v1

double(x) := 2 * x

package rules

import data.lib
import rego.v1

result := lib.double(21)

Evaluating data.rules.result after loading these two policies fails with:

Error:
--> rules.rego:6:21
  |
6 | result := lib.double(21)
  |                     ^
error: could not find function lib.double

Using an explicit alias (import data.lib as l / l.double(21)) fails the same way. Referring to the function by its fully qualified name (data.lib.double(21)) works, and so do variable refs through the same import (e.g. lib.some_value). OPA evaluates the sample above to 42.

The compiled path is affected as well: Compiler::compile_from_policy rejects the same program at compile time with error: Unknown function: 'lib.double' for any entrypoint that reaches the call.

I have tested it against commit ed6ae46 (and it reproduces identically on the v0.10.1 tag).

I'm happy to send a PR for both paths if that helps.

[anakrish]

Hey @andrioni, Thank you for reporting this. It would be awesome if you could submit the PR!