enhance `evaluate` & `inline` (#3580)

1 files changed, 8 insertions, 12 deletions

diff --git a/lib/compress.js b/lib/compress.js
index 08728bb4..2bf120b3 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -3059,15 +3059,15 @@ merge(Compressor.prototype, {
         });
         def(AST_Call, function(compressor, cached, depth) {
             var exp = this.expression;
-            if (exp instanceof AST_SymbolRef) {
-                var fn = exp.fixed_value();
-                if (!(fn instanceof AST_Lambda)) return this;
+            var fn = exp instanceof AST_SymbolRef ? exp.fixed_value() : exp;
+            if (fn instanceof AST_Lambda) {
+                if (fn.evaluating) return this;
                 if (fn.name && fn.name.definition().recursive_refs > 0) return this;
-                if (fn.body.length != 1 || !fn.is_constant_expression()) return this;
                 var stat = fn.body[0];
                 if (!(stat instanceof AST_Return)) return this;
                 var args = eval_args(this.args);
                 if (!args) return this;
+                if (!stat.value) return undefined;
                 fn.argnames.forEach(function(sym, i) {
                     var value = args[i];
                     sym.definition().references.forEach(function(node) {
@@ -3077,8 +3077,9 @@ merge(Compressor.prototype, {
                         cached.push(node);
                     });
                 });
-                if (!stat.value) return undefined;
+                fn.evaluating = true;
                 var val = stat.value._eval(compressor, cached, depth);
+                delete fn.evaluating;
                 if (val === stat.value) return this;
                 return val;
             } else if (compressor.option("unsafe") && exp instanceof AST_PropAccess) {
@@ -5280,15 +5281,10 @@ merge(Compressor.prototype, {
         }
         var stat = is_func && fn.body[0];
         var can_inline = compressor.option("inline") && !self.is_expr_pure(compressor);
-        if (can_inline && stat instanceof AST_Return) {
+        if (exp === fn && can_inline && stat instanceof AST_Return) {
             var value = stat.value;
             if (!value || value.is_constant_expression()) {
-                if (value) {
-                    value = value.clone(true);
-                } else {
-                    value = make_node(AST_Undefined, self);
-                }
-                var args = self.args.concat(value);
+                var args = self.args.concat(value || make_node(AST_Undefined, self));
                 return make_sequence(self, args).optimize(compressor);
             }
         }