support template literals (#4601)

1 files changed, 9 insertions, 1 deletions

diff --git a/lib/compress.js b/lib/compress.js
index d65861a6..700f3748 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -4663,6 +4663,9 @@ merge(Compressor.prototype, {
         def(AST_SymbolRef, function(compressor) {
             return !this.is_declared(compressor) || !can_drop_symbol(this);
         });
+        def(AST_Template, function(compressor) {
+            return any(this.expressions, compressor);
+        });
         def(AST_This, return_false);
         def(AST_Try, function(compressor) {
             return any(this.body, compressor)
@@ -4673,7 +4676,7 @@ merge(Compressor.prototype, {
             return unary_side_effects[this.operator]
                 || this.expression.has_side_effects(compressor);
         });
-        def(AST_VarDef, function(compressor) {
+        def(AST_VarDef, function() {
             return this.value;
         });
     })(function(node, func) {
@@ -7015,6 +7018,11 @@ merge(Compressor.prototype, {
         def(AST_SymbolRef, function(compressor) {
             return this.is_declared(compressor) && can_drop_symbol(this) ? null : this;
         });
+        def(AST_Template, function(compressor, first_in_statement) {
+            var expressions = this.expressions;
+            if (expressions.length == 0) return null;
+            return make_sequence(this, expressions).drop_side_effect_free(compressor, first_in_statement);
+        });
         def(AST_This, return_null);
         def(AST_Unary, function(compressor, first_in_statement) {
             var exp = this.expression;