feat(runtime): support set __webpack_public_path__ runtime

.changeset/honest-rabbits-lie.md

@@ -0,0 +1,5 @@
+---
+"@rspack/binding": patch
+---
+
+feat(runtime): support set **webpack_public_path** runtime

crates/rspack_plugin_javascript/src/visitors/dependency/scanner.rs

@@ -7,8 +7,8 @@ use rspack_regex::RspackRegex;
 use sugar_path::SugarPath;
 use swc_core::common::{pass::AstNodePath, Mark, SyntaxContext};
 use swc_core::ecma::ast::{
-  BinExpr, BinaryOp, CallExpr, Callee, Expr, ExprOrSpread, Ident, Lit, MemberExpr, MemberProp,
-  MetaPropExpr, MetaPropKind, ModuleDecl, NewExpr, Tpl,
+  AssignExpr, AssignOp, BinExpr, BinaryOp, CallExpr, Callee, Expr, ExprOrSpread, Ident, Lit,
+  MemberExpr, MemberProp, MetaPropExpr, MetaPropKind, ModuleDecl, NewExpr, Pat, PatOrExpr, Tpl,
 };
 use swc_core::ecma::atoms::js_word;
 use swc_core::ecma::utils::{quote_ident, quote_str};
@@ -300,6 +300,34 @@ impl VisitAstPath for DependencyScanner<'_> {
     expr: &'ast Expr,
     ast_path: &mut AstNodePath<AstParentNodeRef<'r>>,
   ) {
+    if let Expr::Assign(AssignExpr {
+      op: AssignOp::Assign,
+      left: PatOrExpr::Pat(box Pat::Ident(ident)),
+      ..
+    }) = expr
+    {
+      // variable can be assigned
+      if ident.span.ctxt == self.unresolved_ctxt {
+        #[allow(clippy::single_match)]
+        match ident.sym.as_ref() as &str {
+          WEBPACK_PUBLIC_PATH => {
+            let mut new_expr = expr.clone();
+            if let Some(e) = new_expr.as_mut_assign() {
+              e.left = PatOrExpr::Pat(box Pat::Ident(
+                quote_ident!(RuntimeGlobals::PUBLIC_PATH).into(),
+              ))
+            };
+            self.add_presentational_dependency(box ConstDependency::new(
+              new_expr,
+              Some(RuntimeGlobals::PUBLIC_PATH),
+              as_parent_path(ast_path),
+            ));
+          }
+          _ => {}
+        }
+      }
+    }
+
     if let Expr::Ident(ident) = expr {
       if ident.span.ctxt == self.unresolved_ctxt {
         match ident.sym.as_ref() as &str {

packages/rspack/tests/cases/module-variables/webpack-public-path/index.js

@@ -1,3 +1,15 @@
 it("__webpack_public_path__", function () {
-	expect(typeof __webpack_public_path__).toBe("string");
+	expect(__webpack_public_path__).toBe("/");
+	__webpack_public_path__ = "/a";
+	expect(__webpack_public_path__).toBe("/a");
+	const a = __webpack_public_path__;
+	expect(a).toBe("/a");
+	expect(__webpack_require__.p).toBe("/a");
+});
+
+it("__webpack_public_path__ use as local varable", function () {
+	var __webpack_public_path__ = "/test";
+	// __webpack_require__.p set by prev test
+	expect(__webpack_require__.p).toBe("/a");
+	expect(__webpack_public_path__).toBe("/test");
 });