diff --git a/crates/swc/tests/tsc-references/importCallExpression3ES2020.2.minified.js b/crates/swc/tests/tsc-references/importCallExpression3ES2020.2.minified.js
index 43673b1e636c..366b4bbf5392 100644
--- a/crates/swc/tests/tsc-references/importCallExpression3ES2020.2.minified.js
+++ b/crates/swc/tests/tsc-references/importCallExpression3ES2020.2.minified.js
@@ -5,9 +5,8 @@ export class B {
     }
 }
 //// [2.ts]
-async function foo() {
+!async function() {
     class C extends (await import("./0")).B {
     }
     new C().print();
-}
-foo();
+}();
diff --git a/crates/swc/tests/tsc-references/importCallExpressionInAMD3.2.minified.js b/crates/swc/tests/tsc-references/importCallExpressionInAMD3.2.minified.js
index d4fa5efad3a5..e12df3aab3ff 100644
--- a/crates/swc/tests/tsc-references/importCallExpressionInAMD3.2.minified.js
+++ b/crates/swc/tests/tsc-references/importCallExpressionInAMD3.2.minified.js
@@ -23,14 +23,13 @@ define([
     "@swc/helpers/src/_interop_require_wildcard.mjs"
 ], function(require, exports, _interopRequireWildcard) {
     "use strict";
-    async function foo() {
+    Object.defineProperty(exports, "__esModule", {
+        value: !0
+    }), _interopRequireWildcard = _interopRequireWildcard.default, async function() {
         class C extends (await new Promise((resolve, reject)=>require([
                 "./0"
             ], (m)=>resolve(_interopRequireWildcard(m)), reject))).B {
         }
         new C().print();
-    }
-    Object.defineProperty(exports, "__esModule", {
-        value: !0
-    }), _interopRequireWildcard = _interopRequireWildcard.default, foo();
+    }();
 });
diff --git a/crates/swc/tests/tsc-references/importCallExpressionInCJS2.2.minified.js b/crates/swc/tests/tsc-references/importCallExpressionInCJS2.2.minified.js
index 50c658be2c64..eec766ed6af3 100644
--- a/crates/swc/tests/tsc-references/importCallExpressionInCJS2.2.minified.js
+++ b/crates/swc/tests/tsc-references/importCallExpressionInCJS2.2.minified.js
@@ -26,8 +26,7 @@ Object.defineProperty(exports, "__esModule", {
     value: !0
 });
 const _interopRequireWildcard = require("@swc/helpers/lib/_interop_require_wildcard.js").default;
-async function compute(promise) {
+!async function(promise) {
     let j = await promise;
-    return j ? j.foo() : (j = await Promise.resolve().then(()=>_interopRequireWildcard(require("./1")))).backup();
-}
-compute(Promise.resolve().then(()=>_interopRequireWildcard(require("./0"))));
+    j ? j.foo() : (j = await Promise.resolve().then(()=>_interopRequireWildcard(require("./1")))).backup();
+}(Promise.resolve().then(()=>_interopRequireWildcard(require("./0"))));
diff --git a/crates/swc/tests/tsc-references/importCallExpressionInCJS4.2.minified.js b/crates/swc/tests/tsc-references/importCallExpressionInCJS4.2.minified.js
index 29e27dc15fc6..5cc0b2c720fb 100644
--- a/crates/swc/tests/tsc-references/importCallExpressionInCJS4.2.minified.js
+++ b/crates/swc/tests/tsc-references/importCallExpressionInCJS4.2.minified.js
@@ -17,9 +17,8 @@ Object.defineProperty(exports, "__esModule", {
     value: !0
 });
 const _interopRequireWildcard = require("@swc/helpers/lib/_interop_require_wildcard.js").default;
-async function foo() {
+!async function() {
     class C extends (await Promise.resolve().then(()=>_interopRequireWildcard(require("./0")))).B {
     }
     new C().print();
-}
-foo();
+}();
diff --git a/crates/swc/tests/tsc-references/importCallExpressionInUMD3.2.minified.js b/crates/swc/tests/tsc-references/importCallExpressionInUMD3.2.minified.js
index b66fb159d84c..82e2d0a90106 100644
--- a/crates/swc/tests/tsc-references/importCallExpressionInUMD3.2.minified.js
+++ b/crates/swc/tests/tsc-references/importCallExpressionInUMD3.2.minified.js
@@ -25,12 +25,11 @@
     ], factory) : (global = "undefined" != typeof globalThis ? globalThis : global || self) && factory(global.2Ts = {}, global.interopRequireWildcardMjs);
 }(this, function(exports, _interopRequireWildcard) {
     "use strict";
-    async function foo() {
+    Object.defineProperty(exports, "__esModule", {
+        value: !0
+    }), _interopRequireWildcard = _interopRequireWildcard.default, async function() {
         class C extends (await import("./0")).B {
         }
         new C().print();
-    }
-    Object.defineProperty(exports, "__esModule", {
-        value: !0
-    }), _interopRequireWildcard = _interopRequireWildcard.default, foo();
+    }();
 });
diff --git a/crates/swc_ecma_minifier/tests/fixture/next/wrap-contracts/output.js b/crates/swc_ecma_minifier/tests/fixture/next/wrap-contracts/output.js
index 535954d9b7aa..a9f03edec227 100644
--- a/crates/swc_ecma_minifier/tests/fixture/next/wrap-contracts/output.js
+++ b/crates/swc_ecma_minifier/tests/fixture/next/wrap-contracts/output.js
@@ -6313,16 +6313,12 @@
         },
         5546: function(module, __unused_webpack_exports, __webpack_require__) {
             "use strict";
-            var process = __webpack_require__(3454), utils = __webpack_require__(4867), normalizeHeaderName = __webpack_require__(6016), AxiosError = __webpack_require__(723), transitionalDefaults = __webpack_require__(7874), toFormData = __webpack_require__(7675), DEFAULT_CONTENT_TYPE = {
+            var adapter, process = __webpack_require__(3454), utils = __webpack_require__(4867), normalizeHeaderName = __webpack_require__(6016), AxiosError = __webpack_require__(723), transitionalDefaults = __webpack_require__(7874), toFormData = __webpack_require__(7675), DEFAULT_CONTENT_TYPE = {
                 'Content-Type': 'application/x-www-form-urlencoded'
             };
             function setContentTypeIfUnset(headers, value) {
                 !utils.isUndefined(headers) && utils.isUndefined(headers['Content-Type']) && (headers['Content-Type'] = value);
             }
-            function getDefaultAdapter() {
-                var adapter;
-                return 'undefined' != typeof XMLHttpRequest ? adapter = __webpack_require__(5448) : void 0 !== process && '[object process]' === Object.prototype.toString.call(process) && (adapter = __webpack_require__(5448)), adapter;
-            }
             function stringifySafely(rawValue, parser, encoder) {
                 if (utils.isString(rawValue)) try {
                     return (parser || JSON.parse)(rawValue), utils.trim(rawValue);
@@ -6333,7 +6329,7 @@
             }
             var defaults = {
                 transitional: transitionalDefaults,
-                adapter: getDefaultAdapter(),
+                adapter: ('undefined' != typeof XMLHttpRequest ? adapter = __webpack_require__(5448) : void 0 !== process && '[object process]' === Object.prototype.toString.call(process) && (adapter = __webpack_require__(5448)), adapter),
                 transformRequest: [
                     function(data, headers) {
                         if (normalizeHeaderName(headers, 'Accept'), normalizeHeaderName(headers, 'Content-Type'), utils.isFormData(data) || utils.isArrayBuffer(data) || utils.isBuffer(data) || utils.isStream(data) || utils.isFile(data) || utils.isBlob(data)) return data;
@@ -17511,14 +17507,13 @@
                         function deprecate(e, t) {
                             if (config("noDeprecation")) return e;
                             var r = !1;
-                            function deprecated() {
+                            return function() {
                                 if (!r) {
                                     if (config("throwDeprecation")) throw Error(t);
                                     config("traceDeprecation") ? console.trace(t) : console.warn(t), r = !0;
                                 }
                                 return e.apply(this, arguments);
-                            }
-                            return deprecated;
+                            };
                         }
                         function config(e) {
                             try {
@@ -19163,7 +19158,7 @@
                             return bigint ? String(value) : void 0;
                     }
                 }
-                function stringify(value, replacer, space) {
+                return function(value, replacer, space) {
                     if (arguments.length > 1) {
                         let spacer = '';
                         if ('number' == typeof space ? spacer = ' '.repeat(Math.min(space, 10)) : 'string' == typeof space && (spacer = space.slice(0, 10)), null != replacer) {
@@ -19175,8 +19170,7 @@
                         if (0 !== spacer.length) return stringifyIndent('', value, [], spacer, '');
                     }
                     return stringifySimple('', value, []);
-                }
-                return stringify;
+                };
             }
         },
         2399: function(module, __unused_webpack_exports, __webpack_require__) {
@@ -20316,14 +20310,13 @@
                     return exports.deprecate(fn, msg).apply(this, arguments);
                 };
                 var warned = !1;
-                function deprecated() {
+                return function() {
                     if (!warned) {
                         if (process.throwDeprecation) throw Error(msg);
                         process.traceDeprecation ? console.trace(msg) : console.error(msg), warned = !0;
                     }
                     return fn.apply(this, arguments);
-                }
-                return deprecated;
+                };
             };
             var debugs = {}, debugEnvRegex = /^$/;
             if (process.env.NODE_DEBUG) {
diff --git a/crates/swc_ecma_minifier/tests/terser/compress/collapse_vars/issue_1631_3/output.js b/crates/swc_ecma_minifier/tests/terser/compress/collapse_vars/issue_1631_3/output.js
index a3bf4a359b49..9e4ed1a21511 100644
--- a/crates/swc_ecma_minifier/tests/terser/compress/collapse_vars/issue_1631_3/output.js
+++ b/crates/swc_ecma_minifier/tests/terser/compress/collapse_vars/issue_1631_3/output.js
@@ -1,10 +1,7 @@
 function g() {
-    function f() {
-        return (a = 2), 4;
-    }
-    var a = 0,
-        b = 1,
-        t = f();
-    return (b = a + t);
+    var a = 0, b = 1, t = function f() {
+        return a = 2, 4;
+    }();
+    return b = a + t;
 }
 console.log(g());
diff --git a/crates/swc_ecma_minifier/tests/terser/compress/drop_unused/issue_t161_top_retain_3/output.js b/crates/swc_ecma_minifier/tests/terser/compress/drop_unused/issue_t161_top_retain_3/output.js
index 446e64265475..2f276ce45e88 100644
--- a/crates/swc_ecma_minifier/tests/terser/compress/drop_unused/issue_t161_top_retain_3/output.js
+++ b/crates/swc_ecma_minifier/tests/terser/compress/drop_unused/issue_t161_top_retain_3/output.js
@@ -1,4 +1 @@
-function f() {
-    return 2;
-}
-console.log(f(), 3);
+console.log(2, 3);