test(es): Add tests for .swcrc (#4398)

crates/swc/src/config/issue-4390.json

@@ -0,0 +1,34 @@
+[
+    {
+        "test": ".tsx?$",
+        "jsc": {
+            "parser": {
+                "syntax": "typescript",
+                "tsx": true,
+                "decorators": true,
+                "dynamicImport": true
+            },
+            "transform": {
+                "react": {
+                    "refresh": true
+                }
+            }
+        }
+    },
+    {
+        "test": ".jsx?$",
+        "jsc": {
+            "parser": {
+                "syntax": "ecmascript",
+                "jsx": true,
+                "decorators": true,
+                "dynamicImport": true
+            },
+            "transform": {
+                "react": {
+                    "refresh": true
+                }
+            }
+        }
+    }
+]

crates/swc/src/config/tests.rs

@@ -1,16 +1,24 @@
 use serde_json;
 
-use super::Rc;
-use crate::Options;
+use crate::{parse_swcrc, Options};
 
 #[test]
 fn object() {
-    let _: Rc = serde_json::from_str(include_str!("object.json")).expect("failed to parse");
+    let rc = parse_swcrc(include_str!("object.json")).expect("failed to parse");
+    dbg!(&rc);
 }
 
 #[test]
 fn array() {
-    let _: Rc = serde_json::from_str(include_str!("array.json")).expect("failed to parse");
+    let rc = parse_swcrc(include_str!("array.json")).expect("failed to parse");
+
+    dbg!(&rc);
+}
+
+#[test]
+fn issue_4390() {
+    let rc = parse_swcrc(include_str!("issue-4390.json")).expect("failed to parse");
+    dbg!(&rc);
 }
 
 #[test]

crates/swc/src/lib.rs

@@ -1269,6 +1269,12 @@ impl Compiler {
 
 #[tracing::instrument(level = "info", skip_all)]
 fn load_swcrc(path: &Path) -> Result<Rc, Error> {
+    let content = read_to_string(path).context("failed to read config (.swcrc) file")?;
+
+    parse_swcrc(&content)
+}
+
+fn parse_swcrc(s: &str) -> Result<Rc, Error> {
     fn convert_json_err(e: serde_json::Error) -> Error {
         let line = e.line();
         let column = e.column();
@@ -1285,15 +1291,13 @@ fn load_swcrc(path: &Path) -> Result<Rc, Error> {
         ))
     }
 
-    let content = read_to_string(path).context("failed to read config (.swcrc) file")?;
-
     if let Ok(v) = serde_json::from_reader(StripComments::new(
-        content.trim_start_matches('\u{feff}').as_bytes(),
+        s.trim_start_matches('\u{feff}').as_bytes(),
     )) {
         return Ok(v);
     }
 
-    serde_json::from_reader::<StripComments<&[u8]>, Config>(StripComments::new(content.as_bytes()))
+    serde_json::from_reader::<StripComments<&[u8]>, Config>(StripComments::new(s.as_bytes()))
         .map(Rc::Single)
         .map_err(convert_json_err)
 }