fix corner case in default_values (#5337)

fixes #5336

lib/compress.js

@@ -6830,8 +6830,8 @@ Compressor.prototype.compress = function(node) {
                     unused_fn_names.push(node);
                 }
                 if (!(node instanceof AST_Accessor)) {
-                    var args, spread;
+                    var args, spread, trim = compressor.drop_fargs(node, parent);
-                    if (parent instanceof AST_Call && parent.expression === node) {
+                    if (trim && parent instanceof AST_Call && parent.expression === node) {
                         args = parent.args;
                         for (spread = 0; spread < args.length; spread++) {
                             if (args[spread] instanceof AST_Spread) break;
@@ -6861,8 +6861,8 @@ Compressor.prototype.compress = function(node) {
                             }
                         }
                         node.rest = rest;
+                        if (rest) trim = false;
                     }
-                    var trim = compressor.drop_fargs(node, parent) && !node.rest;
                     var default_length = trim ? -1 : node.length();
                     for (var i = argnames.length; --i >= 0;) {
                         var sym = argnames[i];

test/compress/default-values.js

@@ -2007,6 +2007,7 @@ issue_5192: {
 
 issue_5246_1: {
     options = {
+        keep_fargs: false,
         pure_getters: true,
         unused: true,
     }
@@ -2016,20 +2017,20 @@ issue_5246_1: {
         }("foo"));
     }
     expect: {
-        console.log(function({} = 0) {
+        console.log(function() {
             return "PASS";
-        }("foo"));
+        }());
     }
     expect_stdout: "PASS"
     expect_warnings: [
-        "INFO: Dropping unused default argument value {}=42 [test/compress/default-values.js:1,29]",
+        "INFO: Dropping unused default argument {}=42 [test/compress/default-values.js:1,29]",
-        "INFO: Dropping unused default argument value {}=0 [test/compress/default-values.js:1,29]",
     ]
     node_version: ">=6"
 }
 
 issue_5246_2: {
     options = {
+        keep_fargs: false,
         unused: true,
     }
     input: {
@@ -2038,9 +2039,9 @@ issue_5246_2: {
         })("PASS", []);
     }
     expect: {
-        (function(a = "FAIL", []) {
+        (function(a = "FAIL") {
             console.log(a);
-        })("PASS", []);
+        })("PASS");
     }
     expect_stdout: "PASS"
     node_version: ">=6"
@@ -2049,6 +2050,7 @@ issue_5246_2: {
 issue_5246_3: {
     options = {
         default_values: true,
+        keep_fargs: false,
         unused: true,
     }
     input: {
@@ -2121,3 +2123,28 @@ issue_5314_2: {
     expect_stdout: "PASS"
     node_version: ">=6"
 }
+
+issue_5336: {
+    options = {
+        default_values: true,
+        unused: true,
+    }
+    input: {
+        var a;
+        do {
+            (function f(b = console.log("PASS")) {
+                a = f;
+            })(42);
+        } while (a());
+    }
+    expect: {
+        var a;
+        do {
+            (function f(b = console.log("PASS")) {
+                a = f;
+            })(42);
+        } while (a());
+    }
+    expect_stdout: "PASS"
+    node_version: ">=6"
+}

test/compress/destructured.js

@@ -1130,7 +1130,7 @@ drop_unused_2: {
         }
         f();
     }
-    expect:{
+    expect: {
         (function(a) {
             console.log("PASS");
         })();
@@ -3406,6 +3406,7 @@ issue_5288: {
     options = {
         conditionals: true,
         inline: true,
+        keep_fargs: false,
         reduce_vars: true,
         toplevel: true,
         unused: true,
@@ -3421,7 +3422,7 @@ issue_5288: {
         }() ]));
     }
     expect: {
-        while ([ [ console ? console.log("PASS") : 0 ] ], void 0);
+        while (console ? console.log("PASS") : 0, void 0);
     }
     expect_stdout: "PASS"
     node_version: ">=6"

test/compress/rests.js

@@ -349,6 +349,7 @@ retain_funarg_destructured_object_1: {
 
 retain_funarg_destructured_object_2: {
     options = {
+        keep_fargs: false,
         unused: true,
     }
     input: {
@@ -1091,6 +1092,7 @@ issue_5100_2: {
 issue_5108: {
     options = {
         evaluate: true,
+        keep_fargs: false,
         reduce_vars: true,
         rests: true,
         unsafe: true,
@@ -1102,9 +1104,7 @@ issue_5108: {
         }([ "PASS", "FAIL" ]));
     }
     expect: {
-        console.log(function([]) {
+        console.log("PASS");
-            return "PASS";
-        }([]));
     }
     expect_stdout: "PASS"
     node_version: ">=6"
@@ -1208,6 +1208,7 @@ issue_5165_2: {
 
 issue_5246_1: {
     options = {
+        keep_fargs: false,
         reduce_vars: true,
         rests: true,
         unused: true,
@@ -1218,9 +1219,9 @@ issue_5246_1: {
         }([ , function(){} ])[0]);
     }
     expect: {
-        console.log(typeof function([]) {
+        console.log(typeof function() {
             return this && [ function(){} ];
-        }([])[0]);
+        }()[0]);
     }
     expect_stdout: "function"
     node_version: ">=6"
@@ -1228,6 +1229,7 @@ issue_5246_1: {
 
 issue_5246_2: {
     options = {
+        keep_fargs: false,
         reduce_vars: true,
         rests: true,
         toplevel: true,
@@ -1249,6 +1251,7 @@ issue_5246_2: {
 
 issue_5246_3: {
     options = {
+        keep_fargs: false,
         unused: true,
     }
     input: {

test/compress/yields.js

@@ -1375,6 +1375,7 @@ issue_5076_1: {
     options = {
         evaluate: true,
         hoist_vars: true,
+        keep_fargs: false,
         pure_getters: "strict",
         sequences: true,
         side_effects: true,
@@ -1404,6 +1405,7 @@ issue_5076_2: {
     options = {
         evaluate: true,
         hoist_vars: true,
+        keep_fargs: false,
         passes: 2,
         pure_getters: "strict",
         sequences: true,

test/mocha/awaits.js

@@ -7,7 +7,7 @@ describe("async", function() {
             "function await() {}",
             "function(await) {}",
             "function() { await; }",
-            "function() { await:{} }",
+            "function() { await: {} }",
             "function() { var await; }",
             "function() { function await() {} }",
             "function() { try {} catch (await) {} }",

test/mocha/yields.js

@@ -6,7 +6,7 @@ describe("generator", function() {
         [
             "function yield() {}",
             "function(yield) {}",
-            "function() { yield:{} }",
+            "function() { yield: {} }",
             "function() { var yield; }",
             "function() { function yield() {} }",
             "function() { try {} catch (yield) {} }",