From 650e63c8aa65aa25b7b00dcd3fe49ff9d9e3c2fa Mon Sep 17 00:00:00 2001
From: "Alex Lam S.L" <alexlamsl@gmail.com>
Date: Fri, 2 Dec 2022 04:14:07 +0200
Subject: [PATCH] improve usability (#5753)

---
 bin/uglifyjs |  1 +
 lib/parse.js |  6 +++++-
 lib/utils.js | 14 +++++++++++---
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/bin/uglifyjs b/bin/uglifyjs
index a2a0257520f..345765a41ee 100755
--- a/bin/uglifyjs
+++ b/bin/uglifyjs
@@ -272,6 +272,7 @@ if (typeof options.sourceMap == "object" && "base" in options.sourceMap) {
 if (specified["self"]) {
     if (paths.length) UglifyJS.AST_Node.warn("Ignoring input files since --self was passed");
     if (!options.wrap) options.wrap = "UglifyJS";
+    if (!("toplevel" in options)) options.toplevel = false;
     paths = UglifyJS.FILES;
 } else if (paths.length) {
     paths = simple_glob(paths);
diff --git a/lib/parse.js b/lib/parse.js
index ffd6cd5b69b..258e86e651d 100644
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -207,7 +207,11 @@ function JS_Parse_Error(message, filename, line, col, pos) {
     this.line = line;
     this.col = col;
     this.pos = pos;
-    configure_error_stack(this, new SyntaxError(message, filename, line, col));
+    try {
+        throw new SyntaxError(message, filename, line, col);
+    } catch (cause) {
+        configure_error_stack(this, cause);
+    }
 }
 JS_Parse_Error.prototype = Object.create(SyntaxError.prototype);
 JS_Parse_Error.prototype.constructor = JS_Parse_Error;
diff --git a/lib/utils.js b/lib/utils.js
index 22b069e1222..779be75ee12 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -65,8 +65,12 @@ function configure_error_stack(ex, cause) {
                 var msg = "" + cause.message;
                 cause = null;
                 var index = stack.indexOf(msg);
-                if (index >= 0) index += msg.length;
-                index = stack.indexOf("\n", index) + 1;
+                if (index < 0) {
+                    index = 0;
+                } else {
+                    index += msg.length;
+                    index = stack.indexOf("\n", index) + 1;
+                }
                 stack = stack.slice(0, index) + stack.slice(stack.indexOf("\n", index) + 1);
             }
             return stack;
@@ -77,7 +81,11 @@ function configure_error_stack(ex, cause) {
 function DefaultsError(msg, defs) {
     this.message = msg;
     this.defs = defs;
-    configure_error_stack(this, new Error(msg));
+    try {
+        throw new Error(msg);
+    } catch (cause) {
+        configure_error_stack(this, cause);
+    }
 }
 DefaultsError.prototype = Object.create(Error.prototype);
 DefaultsError.prototype.constructor = DefaultsError;