fetchTree: add pos to EvalState::forceValue

- This way we improve error messages
  on infinite recursion
- Demo:
  ```nix
  let x = builtins.fetchTree {
    type = "git";
    inherit x;
  };
  in x
  ```
- Before:
  ```bash
  $ nix-instantiate --extra-experimental-features flakes --strict
  error: infinite recursion encountered
  ```
- After:
  ```bash
  $ nix-instantiate --extra-experimental-features flakes --strict
  error: infinite recursion encountered

       at /data/github/kamadorueda/nix/test.nix:3:10:

            2|   type = "git";
            3|   inherit x;
             |          ^
            4| };
  ```

Mentions: #3505
This commit is contained in:
Kevin Amado 2021-10-15 19:21:38 -05:00
parent 18e3d63341
commit e5a27a3b4e
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View file

@ -121,7 +121,7 @@ static void fetchTree(
for (auto & attr : *args[0]->attrs) { for (auto & attr : *args[0]->attrs) {
if (attr.name == state.sType) continue; if (attr.name == state.sType) continue;
state.forceValue(*attr.value); state.forceValue(*attr.value, *attr.pos);
if (attr.value->type() == nPath || attr.value->type() == nString) { if (attr.value->type() == nPath || attr.value->type() == nString) {
auto s = state.coerceToString(*attr.pos, *attr.value, context, false, false); auto s = state.coerceToString(*attr.pos, *attr.value, context, false, false);
attrs.emplace(attr.name, attrs.emplace(attr.name,