fix(node): handle empty 'main' entry in pkg json (#23155)

ext/node/package_json.rs

@@ -213,12 +213,13 @@ impl PackageJson {
     Ok(package_json)
   }
 
-  pub fn main(&self, referrer_kind: NodeModuleKind) -> Option<&String> {
-    if referrer_kind == NodeModuleKind::Esm && self.typ == "module" {
+  pub fn main(&self, referrer_kind: NodeModuleKind) -> Option<&str> {
+    let main = if referrer_kind == NodeModuleKind::Esm && self.typ == "module" {
       self.module.as_ref().or(self.main.as_ref())
     } else {
       self.main.as_ref()
-    }
+    };
+    main.map(|m| m.trim()).filter(|m| !m.is_empty())
   }
 
   pub fn specifier(&self) -> ModuleSpecifier {

ext/node/resolution.rs

@@ -1232,7 +1232,7 @@ impl NodeResolver {
   ) -> Result<Option<ModuleSpecifier>, AnyError> {
     let maybe_main = if mode.is_types() {
       match package_json.types.as_ref() {
-        Some(types) => Some(types),
+        Some(types) => Some(types.as_str()),
         None => {
           // fallback to checking the main entrypoint for
           // a corresponding declaration file

tests/specs/check/npm_pkg_empty_main_entry/__test__.jsonc

@@ -0,0 +1,10 @@
+{
+  "steps": [{
+    "args": "check index.ts",
+    "output": "check.out",
+    "exitCode": 1
+  }, {
+    "args": "run index.ts",
+    "output": "run.out"
+  }]
+}

tests/specs/check/npm_pkg_empty_main_entry/check.out

@@ -0,0 +1,5 @@
+Check file:///[WILDLINE]/index.ts
+error: TS2322 [ERROR]: Type 'number' is not assignable to type 'string'.
+const result: string = add(1, 2);
+      ~~~~~~
+    at file:///[WILDLINE]/index.ts:4:7

tests/specs/check/npm_pkg_empty_main_entry/deno.json

@@ -0,0 +1,3 @@
+{
+  "unstable": ["byonm"]
+}

tests/specs/check/npm_pkg_empty_main_entry/index.ts

@@ -0,0 +1,5 @@
+// this package has an empty "main" entry in its package.json for both the package and @types/package
+import { add } from "package";
+
+const result: string = add(1, 2);
+console.log(result);

tests/specs/check/npm_pkg_empty_main_entry/node_modules/@types/package/index.d.ts

@@ -0,0 +1 @@
+export function add(a: number, b: number): number;

tests/specs/check/npm_pkg_empty_main_entry/node_modules/@types/package/package.json

@@ -0,0 +1,3 @@
+{
+  "main": ""
+}

tests/specs/check/npm_pkg_empty_main_entry/node_modules/package/index.js

@@ -0,0 +1 @@
+module.exports.add = (a, b) => a + b;

tests/specs/check/npm_pkg_empty_main_entry/node_modules/package/package.json

@@ -0,0 +1,3 @@
+{
+  "main": ""
+}

tests/specs/check/npm_pkg_empty_main_entry/package.json

@@ -0,0 +1,6 @@
+{
+  "dependencies": {
+    "package": "*",
+    "@types/package": "*"
+  }
+}

tests/specs/check/npm_pkg_empty_main_entry/run.out

@@ -0,0 +1 @@
+3