Fix stack overflow when calculating wasm function signature (#1100)

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> [!IMPORTANT]
> Fix stack overflow in WebAssembly function signature calculation and
improve logging, error handling, and testing.
> 
>   - **Behavior**:
> - Fix stack overflow in `get_dummy_value()` in `mod.rs` by correctly
handling `Constrained` field types.
> - Initialize `wasm_logger` in `on_wasm_init()` in `mod.rs` to enable
logging of `info` messages.
>   - **Debugging**:
> - Add `Debug` trait to `WasmError`, `WasmFunction`, `WasmSpan`,
`WasmGeneratorConfig`, `WasmParentFunction`, `WasmTestCase`, and
`WasmParam` in `mod.rs`.
>   - **Testing**:
> - Add `test_diagnostics_no_errors_2()` in `test_file_manager.rs` to
verify diagnostics with no errors.
> - Update `test_diagnostics_no_errors()` in `test_file_manager.rs` to
include function listing.
>   - **TypeScript**:
> - Fix `requestDiagnostics()` in `baml_project_manager.ts` to handle
undefined runtime.
>     - Add error handling for `runtime_updated` request in `server.ts`.
> 
> <sup>This description was created by </sup>[<img alt="Ellipsis"
src="https://img.shields.io/badge/Ellipsis-blue?color=175173">](https://www.ellipsis.dev?ref=BoundaryML%2Fbaml&utm_source=github&utm_medium=referral)<sup>
for 48fae24. It will automatically
update as commits are pushed.</sup>

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engine/baml-schema-wasm/src/runtime_wasm/mod.rs

@@ -55,6 +55,8 @@ pub fn on_wasm_init() {
             const LOG_LEVEL: log::Level = log::Level::Warn;
         }
     };
+    // This line is required if we want to see normal log::info! messages in JS console logs.
+    wasm_logger::init(wasm_logger::Config::new(LOG_LEVEL));
     match console_log::init_with_level(LOG_LEVEL) {
         Ok(_) => web_sys::console::log_1(
             &format!("Initialized BAML runtime logging as log::{}", LOG_LEVEL).into(),
@@ -140,6 +142,7 @@ impl WasmDiagnosticError {
 }
 
 #[wasm_bindgen(getter_with_clone, inspectable)]
+#[derive(Debug)]
 pub struct WasmError {
     #[wasm_bindgen(readonly)]
     pub r#type: String,
@@ -282,7 +285,7 @@ pub struct WasmRuntime {
 }
 
 #[wasm_bindgen(getter_with_clone, inspectable)]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct WasmFunction {
     #[wasm_bindgen(readonly)]
     pub name: String,
@@ -297,7 +300,7 @@ pub struct WasmFunction {
 }
 
 #[wasm_bindgen(getter_with_clone, inspectable)]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct WasmSpan {
     #[wasm_bindgen(readonly)]
     pub file_path: String,
@@ -312,7 +315,7 @@ pub struct WasmSpan {
 }
 
 #[wasm_bindgen(getter_with_clone, inspectable)]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct WasmGeneratorConfig {
     #[wasm_bindgen(readonly)]
     pub output_type: String,
@@ -348,7 +351,7 @@ impl Default for WasmSpan {
 }
 
 #[wasm_bindgen(getter_with_clone, inspectable)]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct WasmParentFunction {
     #[wasm_bindgen(readonly)]
     pub start: usize,
@@ -359,7 +362,7 @@ pub struct WasmParentFunction {
 }
 
 #[wasm_bindgen(getter_with_clone, inspectable)]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct WasmTestCase {
     #[wasm_bindgen(readonly)]
     pub name: String,
@@ -374,7 +377,7 @@ pub struct WasmTestCase {
 }
 
 #[wasm_bindgen(getter_with_clone, inspectable)]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct WasmParam {
     #[wasm_bindgen(readonly)]
     pub name: String,
@@ -783,7 +786,9 @@ fn get_dummy_value(
             Some(format!("({},)", dummy))
         }
         baml_runtime::FieldType::Optional(_) => None,
-        baml_runtime::FieldType::Constrained{ base, .. } => get_dummy_value(indent, allow_multiline, t)
+        baml_runtime::FieldType::Constrained { base, .. } => {
+            get_dummy_value(indent, allow_multiline, base)
+        }
     }
 }
 

engine/baml-schema-wasm/tests/test_file_manager.rs

@@ -1,3 +1,5 @@
+// Run from the baml-schema-wasm folder with:
+// wasm-pack test --node
 #[cfg(test)]
 mod tests {
     use std::collections::HashMap;
@@ -17,13 +19,7 @@ mod tests {
     /// Sample BAML content for testing.
     fn sample_baml_content() -> String {
         r##"
-        generator lang_python {
-            language python
-            project_root "../"
-            test_command "poetry run pytest"
-            install_command "poetry add baml@latest"
-            package_version_command "poetry show baml"
-        }
+        
         
         class Email {
             subject string
@@ -139,4 +135,41 @@ mod tests {
 
         assert!(diagnostics.errors().is_empty());
     }
+
+    #[wasm_bindgen_test]
+    fn test_diagnostics_no_errors_2() {
+        wasm_logger::init(wasm_logger::Config::new(log::Level::Info));
+        let sample_baml_content = r##"
+function PredictAgeBare(inp: string @assert(big_enough, {{this|length > 1}}) ) -> int  {
+  client "openai/gpt-4o"
+  prompt #"
+    Using your understanding of the historical popularity
+    of names, predict the age of a person with the name
+    {{ inp }} in years. Also predict their genus and
+    species. It's Homo sapiens (with exactly that spelling).
+
+    {{ctx.output_format}}
+  "#
+}
+
+        "##;
+        let mut files = HashMap::new();
+        files.insert("error.baml".to_string(), sample_baml_content.to_string());
+        let files_js = to_value(&files).unwrap();
+        let project = WasmProject::new("baml_src", files_js)
+            .map_err(JsValue::from)
+            .unwrap();
+
+        let env_vars = [("OPENAI_API_KEY", "12345")]
+            .iter()
+            .cloned()
+            .collect::<HashMap<_, _>>();
+        let env_vars_js = to_value(&env_vars).unwrap();
+
+        let current_runtime = project.runtime(env_vars_js).map_err(JsValue::from).unwrap();
+        let diagnostics = project.diagnostics(&current_runtime);
+        current_runtime.list_functions();
+
+        assert!(diagnostics.errors().is_empty());
+    }
 }

typescript/vscode-ext/packages/language-server/src/lib/baml_project_manager.ts

@@ -167,7 +167,7 @@ class Project {
           .map(([path, content]) => [URI.file(path).toString(), content]),
       )
       const diagnostics = this.wasmProject.diagnostics(this.current_runtime)
-      this.onSuccess(this.wasmProject.diagnostics(this.current_runtime), fileMap)
+      this.onSuccess(diagnostics, fileMap)
     }
   }
 
@@ -622,7 +622,11 @@ class BamlProjectManager {
     await this.wrapAsync(async () => {
       for (const project of this.projects.values()) {
         project.requestDiagnostics()
-        this.notifier({ type: 'runtime_updated', root_path: project.rootPath(), files: project.files() })
+        if (project.runtime()) {
+          this.notifier({ type: 'runtime_updated', root_path: project.rootPath(), files: project.files() })
+        } else {
+          console.log('undefined runtime')
+        }
       }
     })
   }

typescript/vscode-ext/packages/language-server/src/server.ts

@@ -80,7 +80,9 @@ export function startServer(options?: LSOptions): void {
       switch (params.type) {
         case 'runtime_updated':
           // console.log(`runtime_updated today! ${Object.keys(params.files).length}: ${Object.entries(params.files).length}`)
-          connection.sendRequest('runtime_updated', params)
+          connection.sendRequest('runtime_updated', params).catch((e) => {
+            console.error('Error sending runtime_updated: ' + e)
+          })
           break
         case 'diagnostic':
           params.errors.forEach(([uri, diagnostics]) => {