chore: add panic test for extensions without a leading dot

src/options.rs

@@ -83,7 +83,7 @@ pub struct ResolveOptions {
     /// If multiple files share the same name but have different extensions,
     /// will resolve the one with the extension listed first in the array and skip the rest.
     ///
-    /// All extensions must begin with a leading dot.
+    /// All extensions must have a leading dot.
     ///
     /// Default `[".js", ".json", ".node"]`
     pub extensions: Vec<String>,

src/tests/extensions.rs

@@ -114,3 +114,12 @@ fn multi_dot_extension() {
         assert_eq!(resolution, Err(error), "{comment} {request} {resolution:?}");
     }
 }
+
+#[test]
+#[should_panic = "All extensions must start with a leading dot"]
+fn without_leading_dot() {
+    Resolver::new(ResolveOptions {
+        extensions: vec!["ts".into(), "js".into()],
+        ..ResolveOptions::default()
+    });
+}

tests/integration_test.rs

@@ -95,5 +95,7 @@ fn options_api() {
         .with_main_field("asdf")
         .with_fully_specified(true)
         .with_prefer_relative(true)
-        .with_prefer_absolute(true);
+        .with_prefer_absolute(true)
+        .with_module("module")
+        .with_main_file("main");
 }