fix(es/minifier): Inline block stmt into expr (#11107)

**Related issue:** - Closes #11103

Author: Austaras

.changeset/two-rules-draw.md

@@ -0,0 +1,6 @@
+---
+swc_core: patch
+swc_ecma_minifier: patch
+---
+
+fix(es/minifier): Inline block stmt into expr

crates/swc_ecma_minifier/src/compress/optimize/iife.rs

@@ -1042,46 +1042,8 @@ impl Optimizer<'_> {
  vars
  }
 
- fn inline_fn_like<'a>(
- &mut self,
- params: impl Iterator<Item = &'a Ident> + Clone,
- params_len: usize,
- body: &mut BlockStmt,
- args: &mut [ExprOrSpread],
- ) -> Option<Expr> {
- if !self.can_inline_fn_like(params.clone(), params_len, &*body, false) {
- return None;
- }
-
- if self.vars.inline_with_multi_replacer(body) {
- self.changed = true;
- }
-
- let mut exprs = Vec::new();
- let vars = self.inline_fn_param(params, params_len, args, &mut exprs);
-
- if args.len() > params_len {
- for arg in &mut args[params_len..] {
- exprs.push(arg.expr.take());
- }
- }
-
- if !vars.is_empty() {
- trace_op!("iife: Creating variables: {:?}", vars);
-
- self.prepend_stmts.push(
- VarDecl {
- span: DUMMY_SP,
- kind: VarDeclKind::Var,
- declare: Default::default(),
- decls: vars,
- ..Default::default()
- }
- .into(),
- );
- }
-
- for mut stmt in body.stmts.take() {
+ fn inline_into_expr(&mut self, stmts: Vec<Stmt>, exprs: &mut Vec<Box<Expr>>) -> Option<Expr> {
+ for mut stmt in stmts {
  match stmt {
  Stmt::Decl(Decl::Var(ref mut var)) => {
  for decl in &mut var.decls {
@@ -1115,14 +1077,20 @@ impl Optimizer<'_> {
  exprs.push(stmt.expr);
  }
 
+ Stmt::Block(stmt) => {
+ if let Some(e) = self.inline_into_expr(stmt.stmts, exprs) {
+ return Some(e);
+ }
+ }
+
  Stmt::Return(stmt) => {
  let span = stmt.span;
  let val = *stmt.arg.unwrap_or_else(|| Expr::undefined(span));
  exprs.push(Box::new(val));
 
  let mut e = SeqExpr {
  span: DUMMY_SP,
- exprs,
+ exprs: exprs.take(),
  };
  self.merge_sequences_in_seq_expr(&mut e);
 
@@ -1134,6 +1102,52 @@ impl Optimizer<'_> {
  }
  }
 
+ None
+ }
+
+ fn inline_fn_like<'a>(
+ &mut self,
+ params: impl Iterator<Item = &'a Ident> + Clone,
+ params_len: usize,
+ body: &mut BlockStmt,
+ args: &mut [ExprOrSpread],
+ ) -> Option<Expr> {
+ if !self.can_inline_fn_like(params.clone(), params_len, &*body, false) {
+ return None;
+ }
+
+ if self.vars.inline_with_multi_replacer(body) {
+ self.changed = true;
+ }
+
+ let mut exprs = Vec::new();
+ let vars = self.inline_fn_param(params, params_len, args, &mut exprs);
+
+ if args.len() > params_len {
+ for arg in &mut args[params_len..] {
+ exprs.push(arg.expr.take());
+ }
+ }
+
+ if !vars.is_empty() {
+ trace_op!("iife: Creating variables: {:?}", vars);
+
+ self.prepend_stmts.push(
+ VarDecl {
+ span: DUMMY_SP,
+ kind: VarDeclKind::Var,
+ declare: Default::default(),
+ decls: vars,
+ ..Default::default()
+ }
+ .into(),
+ );
+ }
+
+ if let Some(e) = self.inline_into_expr(body.stmts.take(), &mut exprs) {
+ return Some(e);
+ }
+
  if let Some(last) = exprs.last_mut() {
  *last = UnaryExpr {
  span: DUMMY_SP,

crates/swc_ecma_minifier/tests/fixture/issues/11103/input.js

@@ -0,0 +1,13 @@
+import assert from "node:assert";
+const miniDynamics = () => {
+ if (true) {
+ let url = "api";
+ url += "/";
+ return new URL(url, "https://example.com").toString();
+ }
+};
+let url = miniDynamics();
+assert(url === "https://example.com/api/");
+export default function Home() {
+ return React.createElement("p", null, url);
+}

crates/swc_ecma_minifier/tests/fixture/issues/11103/output.js

@@ -0,0 +1,6 @@
+import assert from "node:assert";
+let url = new URL("api/", "https://example.com").toString();
+assert("https://example.com/api/" === url);
+export default function Home() {
+ return React.createElement("p", null, url);
+}