add pos to EvalState::forceValue

- This way we improve error messages
  on infinite recursion
- Demo:
  ```nix
  let
    x = builtins.fetchMercurial x;
  in
  x
  ```
- Before:
  ```bash
  $ nix-instantiate --show-trace --strict
  error: infinite recursion encountered
  ```
- After:
  ```bash
  nix-instantiate --show-trace --strict
  error: infinite recursion encountered

       at /data/github/kamadorueda/test/default.nix:2:7:

            1| let
            2|   x = builtins.fetchMercurial x;
             |       ^
            3| in
  ```

Mentions: #3505
This commit is contained in:
Kevin Amado 2021-10-14 23:23:04 -05:00
parent 4c0cde95ad
commit 1bdeef8395
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View file

@ -15,7 +15,7 @@ static void prim_fetchMercurial(EvalState & state, const Pos & pos, Value * * ar
std::string name = "source";
PathSet context;
state.forceValue(*args[0]);
state.forceValue(*args[0], pos);
if (args[0]->type() == nAttrs) {