fix: workaround for #1838

This is currently not ideal in form but should inform a larger fix

crates/fm/src/lib.rs

@@ -70,7 +70,7 @@ impl FileManager {
         // Unwrap as we ensure that all file_id's map to a corresponding file in the file map
         self.file_map.get_file(file_id).unwrap()
     }
-    fn path(&mut self, file_id: FileId) -> &Path {
+    pub fn path(&self, file_id: FileId) -> &Path {
         // Unwrap as we ensure that all file_ids are created by the file manager
         // So all file_ids will points to a corresponding path
         self.id_to_path.get(&file_id).unwrap().0.as_path()

crates/lsp/Cargo.toml

@@ -16,6 +16,7 @@ noirc_driver.workspace = true
 noirc_errors.workspace = true
 noirc_frontend.workspace = true
 serde_json.workspace = true
+toml.workspace = true
 tower.workspace = true
 async-lsp = { version = "0.0.4", default-features = false, features = ["omni-trait"] }
 

crates/lsp/src/lib.rs

@@ -1,6 +1,9 @@
 use std::{
+    collections::HashMap,
+    fs,
     future::Future,
     ops::{self, ControlFlow},
+    path::{Path, PathBuf},
     pin::Pin,
     task::{Context, Poll},
 };
@@ -20,7 +23,7 @@ use lsp_types::{
 };
 use noirc_driver::Driver;
 use noirc_errors::{DiagnosticKind, FileDiagnostic};
-use noirc_frontend::graph::CrateType;
+use noirc_frontend::graph::{CrateName, CrateType};
 use serde_json::Value as JsonValue;
 use tower::Service;
 
@@ -134,13 +137,8 @@ fn on_code_lens_request(
     params: CodeLensParams,
 ) -> impl Future<Output = Result<Option<Vec<CodeLens>>, ResponseError>> {
     async move {
-        // TODO: Requiring `Language` and `is_opcode_supported` to construct a driver makes for some real stinky code
-        // The driver should not require knowledge of the backend; instead should be implemented as an independent pass (in nargo?)
-        let mut driver = Driver::new(&Language::R1CS, Box::new(|_op| false));
-
-        let file_path = &params.text_document.uri.to_file_path().unwrap();
-
-        driver.create_local_crate(file_path, CrateType::Binary);
+        let actual_path = params.text_document.uri.to_file_path().unwrap();
+        let mut driver = create_driver_at_path(actual_path);
 
         // We ignore the warnings and errors produced by compilation for producing codelenses
         // because we can still get the test functions even if compilation fails
@@ -218,33 +216,76 @@ fn on_did_close_text_document(
     ControlFlow::Continue(())
 }
 
+/// Find the nearest parent file with given names.
+fn find_nearest_parent_file(path: &Path, filenames: &[&str]) -> Option<PathBuf> {
+    let mut current_path = path;
+
+    while let Some(parent_path) = current_path.parent() {
+        for filename in filenames {
+            let mut possible_file_path = parent_path.to_path_buf();
+            possible_file_path.push(filename);
+            if possible_file_path.is_file() {
+                return Some(possible_file_path);
+            }
+        }
+        current_path = parent_path;
+    }
+
+    None
+}
+
+fn read_dependencies(
+    nargo_toml_path: &Path,
+) -> Result<HashMap<String, String>, Box<dyn std::error::Error>> {
+    let content: String = fs::read_to_string(nargo_toml_path)?;
+    let value: toml::Value = toml::from_str(&content)?;
+
+    let mut dependencies = HashMap::new();
+
+    if let Some(toml::Value::Table(table)) = value.get("dependencies") {
+        for (key, value) in table {
+            if let toml::Value::Table(inner_table) = value {
+                if let Some(toml::Value::String(path)) = inner_table.get("path") {
+                    dependencies.insert(key.clone(), path.clone());
+                }
+            }
+        }
+    }
+
+    Ok(dependencies)
+}
+
 fn on_did_save_text_document(
     state: &mut LspState,
     params: DidSaveTextDocumentParams,
 ) -> ControlFlow<Result<(), async_lsp::Error>> {
-    // TODO: Requiring `Language` and `is_opcode_supported` to construct a driver makes for some real stinky code
-    // The driver should not require knowledge of the backend; instead should be implemented as an independent pass (in nargo?)
-    let mut driver = Driver::new(&Language::R1CS, Box::new(|_op| false));
-
-    let file_path = &params.text_document.uri.to_file_path().unwrap();
-
-    driver.create_local_crate(file_path, CrateType::Binary);
-
-    let mut diagnostics = Vec::new();
+    let actual_path = params.text_document.uri.to_file_path().unwrap();
+    let mut driver = create_driver_at_path(actual_path.clone());
 
     let file_diagnostics = match driver.check_crate(false) {
         Ok(warnings) => warnings,
         Err(errors_and_warnings) => errors_and_warnings,
     };
+    let mut diagnostics = Vec::new();
 
     if !file_diagnostics.is_empty() {
         let fm = driver.file_manager();
         let files = fm.as_simple_files();
 
         for FileDiagnostic { file_id, diagnostic } in file_diagnostics {
-            // TODO(#1681): This file_id never be 0 because the "path" where it maps is the directory, not a file
-            if file_id.as_usize() != 0 {
-                continue;
+            // TODO(AD): HACK, undo these total hacks once we have a proper approach
+            if file_id.as_usize() == 0 {
+                // main.nr case
+                if actual_path.file_name().unwrap().to_str() != Some("main.nr")
+                    && actual_path.file_name().unwrap().to_str() != Some("lib.nr")
+                {
+                    continue;
+                }
+            } else if fm.path(file_id).file_name().unwrap().to_str().unwrap()
+                != actual_path.file_name().unwrap().to_str().unwrap().replace(".nr", "")
+            {
+                // every other file case
+                continue; // TODO(AD): HACK, we list all errors, filter by hacky final path component
             }
 
             let mut range = Range::default();
@@ -278,6 +319,37 @@ fn on_did_save_text_document(
     ControlFlow::Continue(())
 }
 
+fn create_driver_at_path(actual_path: PathBuf) -> Driver {
+    // TODO: Requiring `Language` and `is_opcode_supported` to construct a driver makes for some real stinky code
+    // The driver should not require knowledge of the backend; instead should be implemented as an independent pass (in nargo?)
+    let mut driver = Driver::new(&Language::R1CS, Box::new(|_op| false));
+
+    let mut file_path: PathBuf = actual_path;
+    // TODO better naming/unhacking
+    if let Some(new_path) = find_nearest_parent_file(&file_path, &["lib.nr", "main.nr"]) {
+        file_path = new_path.clone(); // TODO unhack
+    }
+    let nargo_toml_path = find_nearest_parent_file(&file_path, &["Nargo.toml"]);
+
+    driver.create_local_crate(file_path, CrateType::Binary);
+
+    // TODO(AD): undo hacky dependency resolution
+    if let Some(nargo_toml_path) = nargo_toml_path {
+        let dependencies = read_dependencies(&nargo_toml_path);
+        if let Ok(dependencies) = dependencies {
+            for (crate_name, dependency_path) in dependencies.iter() {
+                let path_to_lib = nargo_toml_path
+                    .parent()
+                    .unwrap() // TODO
+                    .join(PathBuf::from(&dependency_path).join("src").join("lib.nr"));
+                let library_crate = driver.create_non_local_crate(path_to_lib, CrateType::Library);
+                driver.propagate_dep(library_crate, &CrateName::new(crate_name).unwrap());
+            }
+        }
+    }
+    driver
+}
+
 fn on_exit(_state: &mut LspState, _params: ()) -> ControlFlow<Result<(), async_lsp::Error>> {
     ControlFlow::Continue(())
 }