fix various corner cases (#3126)

- augment ufuzz/reminify test options

fixes #3125

Author: alexlamsl

lib/compress.js

@@ -491,7 +491,10 @@ merge(Compressor.prototype, {
                 mark_escaped(tw, d, scope, parent, value, level + 1, depth + 1);
                 if (value) return;
             }
-            if (level == 0) d.direct_access = true;
+            if (level > 0) return;
+            if (parent instanceof AST_Sequence && node !== parent.tail_node()) return;
+            if (parent instanceof AST_SimpleStatement) return;
+            d.direct_access = true;
         }
 
         var suppressor = new TreeWalker(function(node) {
@@ -509,17 +512,21 @@ merge(Compressor.prototype, {
             walk_defuns(tw, this);
             return true;
         });
-        def(AST_Assign, function(tw) {
+        def(AST_Assign, function(tw, descend, compressor) {
             var node = this;
-            if (!(node.left instanceof AST_SymbolRef)) return;
-            var d = node.left.definition();
+            var sym = node.left;
+            if (!(sym instanceof AST_SymbolRef)) return;
+            var d = sym.definition();
             var fixed = d.fixed;
             if (!fixed && node.operator != "=") return;
-            if (!safe_to_assign(tw, d, node.left.scope, node.right)) return;
-            d.references.push(node.left);
+            if (!safe_to_assign(tw, d, sym.scope, node.right)) return;
+            var eq = node.operator == "=";
+            var value = eq ? node.right : node;
+            if (is_modified(compressor, tw, node, value, 0)) return;
+            d.references.push(sym);
             d.assignments++;
-            if (node.operator != "=") d.chained = true;
-            d.fixed = node.operator == "=" ? function() {
+            if (!eq) d.chained = true;
+            d.fixed = eq ? function() {
                 return node.right;
             } : function() {
                 return make_node(AST_Binary, node, {
@@ -531,6 +538,7 @@ merge(Compressor.prototype, {
             mark(tw, d, false);
             node.right.walk(tw);
             mark(tw, d, true);
+            mark_escaped(tw, d, sym.scope, node, value, 0, 1);
             return true;
         });
         def(AST_Binary, function(tw) {
@@ -4682,13 +4690,16 @@ merge(Compressor.prototype, {
                     func = func.fixed_value();
                 }
                 if (func instanceof AST_Lambda && !func.contains_this()) {
-                    return make_sequence(this, [
+                    return (self.args.length ? make_sequence(this, [
                         self.args[0],
                         make_node(AST_Call, self, {
                             expression: exp.expression,
                             args: self.args.slice(1)
                         })
-                    ]).optimize(compressor);
+                    ]) : make_node(AST_Call, self, {
+                        expression: exp.expression,
+                        args: []
+                    })).optimize(compressor);
                 }
                 break;
             }

test/compress/functions.js

@@ -2303,3 +2303,19 @@ issue_3076: {
     }
     expect_stdout: "PASS"
 }
+
+issue_3125: {
+    options = {
+        inline: true,
+        unsafe: true,
+    }
+    input: {
+        console.log(function() {
+            return "PASS";
+        }.call());
+    }
+    expect: {
+        console.log("PASS");
+    }
+    expect_stdout: "PASS"
+}

test/compress/reduce_vars.js

@@ -6058,3 +6058,91 @@ conditional_nested_2: {
     }
     expect_stdout: "1"
 }
+
+issue_2436: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var c;
+        console.log(((c = {
+            a: 1,
+            b: 2
+        }).a = 3, {
+            x: c.a,
+            y: c.b
+        }));
+    }
+    expect: {
+        var c;
+        console.log(((c = {
+            a: 1,
+            b: 2
+        }).a = 3, {
+            x: c.a,
+            y: c.b
+        }));
+    }
+    expect_stdout: true
+}
+
+issue_2916: {
+    options = {
+        collapse_vars: true,
+        evaluate: true,
+        inline: true,
+        passes: 2,
+        reduce_vars: true,
+        side_effects: true,
+        unsafe: true,
+        unused: true,
+    }
+    input: {
+        var c = "FAIL";
+        (function(b) {
+            (function(d) {
+                d[0] = 1;
+            })(b);
+            +b && (c = "PASS");
+        })([]);
+        console.log(c);
+    }
+    expect: {
+        var c = "FAIL";
+        (function(b) {
+            b[0] = 1;
+            +b && (c = "PASS");
+        })([]);
+        console.log(c);
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3125: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var o;
+        console.log((function() {
+            this.p++;
+        }.call(o = {
+            p: 6
+        }), o.p));
+    }
+    expect: {
+        var o;
+        console.log((function() {
+            this.p++;
+        }.call(o = {
+            p: 6
+        }), o.p));
+    }
+    expect_stdout: "7"
+}

test/ufuzz.json

@@ -18,6 +18,13 @@
     {
         "toplevel": true
     },
+    {
+        "compress": {
+            "passes": 1e6,
+            "unsafe": true
+        },
+        "toplevel": true
+    },
     {
         "compress": {
             "keep_fargs": false,