Don't compress (0, eval)() to eval()

diff --git a/lib/compress.js b/lib/compress.js
index 16dc90f..df8975d 100644 (file)
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -179,14 +179,16 @@ merge(Compressor.prototype, {
     // we shouldn't compress (1,func)(something) to
     // func(something) because that changes the meaning of
     // the func (becomes lexical instead of global).
-    function maintain_this_binding(parent, orig, val) {
-        if (parent instanceof AST_Call && parent.expression === orig && val instanceof AST_PropAccess) {
-            return make_node(AST_Seq, orig, {
-                car: make_node(AST_Number, orig, {
-                    value: 0
-                }),
-                cdr: val
-            });
+    function maintain_call_binding(parent, orig, val) {
+        if (parent instanceof AST_Call && parent.expression === orig) {
+            if (val instanceof AST_PropAccess || (val instanceof AST_Symbol && val.name === "eval")) {
+                return make_node(AST_Seq, orig, {
+                    car: make_node(AST_Number, orig, {
+                        value: 0
+                    }),
+                    cdr: val
+                });
+            }
         }
         return val;
     }
@@ -381,7 +383,7 @@ merge(Compressor.prototype, {
                 if (is_lvalue(node, parent)) return node;
 
                 // Remove var definition and return its value to the TreeTransformer to replace.
-                var value = maintain_this_binding(parent, node, var_decl.value);
+                var value = maintain_call_binding(parent, node, var_decl.value);
                 var_decl.value = null;
 
                 var_defs.splice(var_defs_index, 1);
@@ -2123,7 +2125,7 @@ merge(Compressor.prototype, {
         if (!compressor.option("side_effects"))
             return self;
         if (!self.car.has_side_effects(compressor)) {
-            return maintain_this_binding(compressor.parent(), self, self.cdr);
+            return maintain_call_binding(compressor.parent(), self, self.cdr);
         }
         if (compressor.option("cascade")) {
             if (self.car instanceof AST_Assign
@@ -2313,10 +2315,10 @@ merge(Compressor.prototype, {
                 if (ll.length > 1) {
                     if (ll[1]) {
                         compressor.warn("Condition left of && always true [{file}:{line},{col}]", self.start);
-                        return maintain_this_binding(compressor.parent(), self, self.right.evaluate(compressor)[0]);
+                        return maintain_call_binding(compressor.parent(), self, self.right.evaluate(compressor)[0]);
                     } else {
                         compressor.warn("Condition left of && always false [{file}:{line},{col}]", self.start);
-                        return maintain_this_binding(compressor.parent(), self, ll[0]);
+                        return maintain_call_binding(compressor.parent(), self, ll[0]);
                     }
                 }
             }
@@ -2325,10 +2327,10 @@ merge(Compressor.prototype, {
                 if (ll.length > 1) {
                     if (ll[1]) {
                         compressor.warn("Condition left of || always true [{file}:{line},{col}]", self.start);
-                        return maintain_this_binding(compressor.parent(), self, ll[0]);
+                        return maintain_call_binding(compressor.parent(), self, ll[0]);
                     } else {
                         compressor.warn("Condition left of || always false [{file}:{line},{col}]", self.start);
-                        return maintain_this_binding(compressor.parent(), self, self.right.evaluate(compressor)[0]);
+                        return maintain_call_binding(compressor.parent(), self, self.right.evaluate(compressor)[0]);
                     }
                 }
             }
@@ -2553,10 +2555,10 @@ merge(Compressor.prototype, {
         if (cond.length > 1) {
             if (cond[1]) {
                 compressor.warn("Condition always true [{file}:{line},{col}]", self.start);
-                return maintain_this_binding(compressor.parent(), self, self.consequent);
+                return maintain_call_binding(compressor.parent(), self, self.consequent);
             } else {
                 compressor.warn("Condition always false [{file}:{line},{col}]", self.start);
-                return maintain_this_binding(compressor.parent(), self, self.alternative);
+                return maintain_call_binding(compressor.parent(), self, self.alternative);
             }
         }
         var negated = cond[0].negate(compressor);

diff --git a/test/compress/issue-973.js b/test/compress/issue-973.js
index 41fb0e2..f2d4401 100644 (file)
--- a/test/compress/issue-973.js
+++ b/test/compress/issue-973.js
@@ -49,4 +49,21 @@ this_binding_collapse_vars: {
         a();
         (0, a.b)();
     }
+}
+
+eval_direct_calls: {
+    options = {
+        side_effects: true,
+        collapse_vars: true
+    }
+    input: {
+        (0, eval)('');
+
+        var fn = eval;
+        fn('');
+    }
+    expect: {
+        (0, eval)('');
+        (0, eval)('');
+    }
 }
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