Add Decodal formatter

crates/decodal-wasm/src/lib.rs

@@ -2,7 +2,7 @@ use std::collections::BTreeMap;
 
 use decodal::{
     Data, Diagnostic, DiagnosticKind, EmptyLoader, Engine, LoadedSource, SourceId, SourceLoader,
-    Span, format_diagnostic_with,
+    Span, format_diagnostic_with, format_source,
 };
 use wasm_bindgen::prelude::*;
 
@@ -11,6 +11,17 @@ pub fn evaluate(source: &str) -> String {
     encode_result(evaluate_inner(source))
 }
 
+#[wasm_bindgen(js_name = formatSource)]
+pub fn format_source_json(source: &str) -> String {
+    match format_source(source) {
+        Ok(formatted) => format!("{{\"ok\":true,\"source\":{}}}", json_string(&formatted)),
+        Err(error) => format!(
+            "{{\"ok\":false,\"error\":{}}}",
+            json_string(&format_diagnostic_with_root(&error, "playground"))
+        ),
+    }
+}
+
 #[wasm_bindgen(js_name = evaluateProject)]
 pub fn evaluate_project(entry: &str, files_json: &str) -> String {
     encode_result(evaluate_project_inner(entry, files_json))
@@ -214,6 +225,13 @@ fn json_string(value: &str) -> String {
 mod tests {
     use super::{evaluate_project_inner, normalize_path, resolve_import};
 
+    #[test]
+    fn formats_source_for_web() {
+        let output = super::format_source_json("value={a=1;};");
+        assert!(output.contains("\"ok\":true"));
+        assert!(output.contains("value = {\\n    a = 1;\\n};\\n"));
+    }
+
     #[test]
     fn normalizes_virtual_paths() {
         assert_eq!(