fix corner case in inline (#3853)

fixes #3852

lib/compress.js

@@ -4179,7 +4179,7 @@ merge(Compressor.prototype, {
             });
         }
         var drop_fn_name = compressor.option("keep_fnames") ? return_false : compressor.option("ie8") ? function(def) {
-            return !compressor.exposed(def) && !def.references.length;
+            return !compressor.exposed(def) && def.references.length == def.replaced;
         } : function(def) {
             // any declarations with same name will overshadow
             // name of this anonymous function and can therefore
@@ -4733,7 +4733,7 @@ merge(Compressor.prototype, {
     }
 
     function all_bool(def, bool_returns, compressor) {
-        return def.bool_fn + (bool_returns[def.id] || 0) === def.references.length
+        return def.bool_fn + (bool_returns[def.id] || 0) === def.references.length - def.replaced
             && !compressor.exposed(def);
     }
 
@@ -4919,7 +4919,7 @@ merge(Compressor.prototype, {
             if (def.assignments != count) return;
             if (def.direct_access) return;
             if (def.escaped.depth == 1) return;
-            if (def.references.length == count) return;
+            if (def.references.length - def.replaced == count) return;
             if (def.single_use) return;
             if (top_retain(def)) return;
             if (sym.fixed_value() !== right) return;
@@ -5009,7 +5009,11 @@ merge(Compressor.prototype, {
                     exprs = trim(exprs, compressor, first_in_statement);
                     return exprs && make_sequence(this, exprs);
                 }
-                if (exp instanceof AST_Function && (!exp.name || !exp.name.definition().references.length)) {
+                if (exp instanceof AST_Function) {
+                    if (exp.name) {
+                        var def = exp.name.definition();
+                        if (def.references.length > def.replaced) return this;
+                    }
                     exp.process_expression(false, function(node) {
                         var value = node.value && node.value.drop_side_effect_free(compressor, true);
                         return value ? make_node(AST_SimpleStatement, node, {
@@ -6177,7 +6181,7 @@ merge(Compressor.prototype, {
                     if (best_of(compressor, self, node) === node) return node;
                 }
                 var scope, in_loop, level = -1;
-                if ((exp === fn || compressor.option("unused") && exp.definition().references.length == 1)
+                if ((exp === fn || compressor.option("unused") && def.references.length - def.replaced == 1)
                     && can_inject_symbols()) {
                     fn._squeezed = true;
                     if (exp !== fn) fn.parent_scope = exp.scope;
@@ -6261,7 +6265,7 @@ merge(Compressor.prototype, {
             if (var_assigned) return;
             if (compressor.option("inline") < 2 && fn.argnames.length) return;
             if (!fn.variables.all(function(def) {
-                return def.references.length < 2 && def.orig[0] instanceof AST_SymbolFunarg;
+                return def.references.length - def.replaced < 2 && def.orig[0] instanceof AST_SymbolFunarg;
             })) return;
             var abort = false;
             var begin;
@@ -7515,7 +7519,8 @@ merge(Compressor.prototype, {
                     }
                     var name_length = def.name.length;
                     if (compressor.option("unused") && !compressor.exposed(def)) {
-                        name_length += (name_length + 2 + value_length) / (def.references.length - def.assignments);
+                        var referenced = def.references.length - def.replaced;
+                        name_length += (name_length + 2 + value_length) / (referenced - def.assignments);
                     }
                     var delta = value_length - Math.floor(name_length);
                     def.should_replace = delta < compressor.eval_threshold ? fn : false;

test/compress/drop-unused.js

@@ -2366,7 +2366,7 @@ function_parameter_ie8: {
     }
     expect: {
         (function() {
-            (function f() {
+            (function() {
                 console.log("PASS");
             })();
         })();

test/compress/functions.js

@@ -4660,3 +4660,24 @@ issue_3836: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3852: {
+    options = {
+        collapse_vars: true,
+        inline: true,
+        unused: true,
+    }
+    input: {
+        console.log(function(a) {
+            return function(b) {
+                return b && (b[0] = 0), "PASS";
+            }(a);
+        }(42));
+    }
+    expect: {
+        console.log(function(a) {
+            return a && (a[0] = 0), "PASS";
+        }(42));
+    }
+    expect_stdout: "PASS"
+}

test/compress/ie8.js

@@ -2389,7 +2389,7 @@ issue_3703: {
         var a = "PASS";
         (function() {
             var b;
-            var c = function g() {
+            var c = function() {
                 a = "FAIL";
             };
             a ? b |= c : b.p;