Importing from a virtual file no longer works

[globin]

I'm using this crate to allow users to "override" a JSON file that is generated.

This worked previously, but seems to have been broken(/changed?) by 772afa0.

Jsonnet: tried to import /.../base.jsonnet from virtual:combined.jsonnet, but imports are not supported

I guess it's due to it being a "virtual" file?

I don't know if there would be a more idiomatic way to achieve this and this is a deliberate change, or if this an actual bug?

pub fn apply_jsonnet_overlays<P: AsRef<Path>>(
    self,
    jsonnet_paths: impl Iterator<Item = P>,
) -> Result<Self, CustomError> {
    let mut jsonnet_paths = jsonnet_paths.peekable();
    if jsonnet_paths.peek().is_none() {
        return Ok(self);
    }

    let mut jsonnet = serde_json::to_string(&self)?;

    for path in jsonnet_paths {
        write!(
            jsonnet,
            "\n + (import {})",
            escape_string_json(&path.as_ref().display().to_string())
        )?;
    }
    trace!("jsonnet_file: {jsonnet}");

    let mut state_builder = StateBuilder::default();
    state_builder.import_resolver(FileImportResolver::new(vec![std::env::current_dir()?]));
    let state = state_builder.build();

    let merged_jsonnet_val = state
        .evaluate_snippet("combined.jsonnet", jsonnet)
        .map_err(|e| CustomError::Jsonnet(e.to_string()))?;

    let json_string = merged_jsonnet_val
        .to_string()
        .map_err(|e| CustomError::Jsonnet(e.to_string()))?;

    Ok(serde_json::from_str(&json_string)?)
}

[CertainLach]

I should document it better, sorry. You need to "enter" the state, because imports only work when you have it entered.

Just adding

let _entered = state.enter();

jrsonnet/crates/jrsonnet-evaluator/src/lib.rs

Lines 317 to 329 in 5d80d31

	pub fn enter(&self) -> StateEnterGuard {
	self.try_enter().expect("entered state already exists")
	}
	pub fn try_enter(&self) -> Option<StateEnterGuard> {
	STATE.with_borrow_mut(|v| {
	if v.is_none() {
	*v = Some(self.clone());
	Some(StateEnterGuard(PhantomData))
	} else {
	None
	}
	})
	}

after

let state = state_builder.build();

Is enough.

In evaluate_snippet the state is being entered automatically, but it is likely that in your case the import is being performed lazily, thus you get Thunk inside of merged_jsonnet_val, which resolves to import. Before it was carried around in Context so it was not a problem.

So when you call to_string - the inner thunk value doesn't know where to get the ImportResolver.

jrsonnet/crates/jrsonnet-evaluator/src/lib.rs

Lines 307 to 314 in 5d80d31

	pub fn with_state<V>(v: impl FnOnce(State) -> V) -> V {
	if let Some(state) = STATE.with_borrow(Clone::clone) {
	v(state)
	} else {
	let s = DEFAULT_STATE.with(Clone::clone);
	v(s)
	}
	}

jrsonnet/crates/jrsonnet-evaluator/src/evaluate/mod.rs

Lines 245 to 260 in 5d80d31

	LExpr::Import {
	kind,
	kind_span,
	path,
	} => with_state(|state| {
	let resolved = state.resolve_from(kind_span.0.source_path(), &path.clone())?;
	Ok::<_, Error>(match kind.value {
	ImportKind::Normal => in_frame(
	CallLocation::new(&kind.span),
	|| "import".to_string(),
	|| state.import_resolved(resolved),
	)?,
	ImportKind::Str => Val::string(state.import_resolved_str(resolved)?),
	ImportKind::Bin => Val::arr(state.import_resolved_bin(resolved)?),
	})
	})?,