fix corner cases in typeofs (#5301)

lib/ast.js

@@ -142,6 +142,7 @@ DEF_BITPROPS(AST_Node, [
     "_squeezed",
     // AST_Call
     "call_only",
+    // AST_Lambda
     "collapse_scanning",
     // AST_SymbolRef
     "defined",

lib/compress.js

@@ -8715,6 +8715,7 @@ Compressor.prototype.compress = function(node) {
     });
 
     function mark_locally_defined(condition, consequent, alternative) {
+        if (condition instanceof AST_Sequence) condition = condition.tail_node();
         if (!(condition instanceof AST_Binary)) return;
         if (!(condition.left instanceof AST_String)) {
             switch (condition.operator) {
@@ -8749,6 +8750,8 @@ Compressor.prototype.compress = function(node) {
         var abort = false;
         var def = sym.definition();
         var fn;
+        var refs = [];
+        var scanned = [];
         var tw = new TreeWalker(function(node, descend) {
             if (abort) return true;
             if (node instanceof AST_Assign) {
@@ -8765,11 +8768,40 @@ Compressor.prototype.compress = function(node) {
             if (node instanceof AST_Call) {
                 descend();
                 fn = node.expression.tail_node();
-                if (fn instanceof AST_Lambda) {
+                var save;
-                    fn.walk(tw);
+                if (fn instanceof AST_SymbolRef) {
-                } else {
+                    fn = fn.fixed_value();
-                    abort = true;
+                    save = refs.length;
                 }
+                if (!(fn instanceof AST_Lambda)) {
+                    abort = true;
+                } else if (push_uniq(scanned, fn)) {
+                    fn.walk(tw);
+                }
+                if (save >= 0) refs.length = save;
+                return true;
+            }
+            if (node instanceof AST_DWLoop) {
+                var save = refs.length;
+                descend();
+                if (abort) refs.length = save;
+                return true;
+            }
+            if (node instanceof AST_For) {
+                if (node.init) node.init.walk(tw);
+                var save = refs.length;
+                if (node.condition) node.condition.walk(tw);
+                node.body.walk(tw);
+                if (node.step) node.step.walk(tw);
+                if (abort) refs.length = save;
+                return true;
+            }
+            if (node instanceof AST_ForEnumeration) {
+                node.object.walk(tw);
+                var save = refs.length;
+                node.init.walk(tw);
+                node.body.walk(tw);
+                if (abort) refs.length = save;
                 return true;
             }
             if (node instanceof AST_Scope) {
@@ -8777,11 +8809,14 @@ Compressor.prototype.compress = function(node) {
                 return true;
             }
             if (node instanceof AST_SymbolRef) {
-                if (node.definition() === def) node.defined = true;
+                if (node.definition() === def) refs.push(node);
                 return true;
             }
         });
         body.walk(tw);
+        refs.forEach(function(ref) {
+            ref.defined = true;
+        });
 
         function negate(node) {
             if (!(node instanceof AST_Binary)) return;

test/compress/typeof.js

@@ -527,6 +527,102 @@ reassign_conditional: {
     node_version: ">=15"
 }
 
+reassign_do: {
+    options = {
+        comparisons: true,
+        conditionals: true,
+        if_return: true,
+        passes: 2,
+        reduce_vars: true,
+        typeofs: true,
+    }
+    input: {
+        A = console;
+        (function() {
+            if ("undefined" == typeof A)
+                return;
+            var a = A, i = 2;
+            do {
+                console.log(void 0 === A, void 0 === a);
+                A = void 0;
+            } while (--i);
+        })();
+    }
+    expect: {
+        A = console;
+        (function() {
+            if ("undefined" != typeof A) {
+                var a = A, i = 2;
+                do {
+                    console.log(void 0 === A, (a, false));
+                    A = void 0;
+                } while (--i);
+            }
+        })();
+    }
+    expect_stdout: [
+        "false false",
+        "true false",
+    ]
+}
+
+reassign_for: {
+    options = {
+        comparisons: true,
+        conditionals: true,
+        passes: 2,
+        reduce_vars: true,
+        toplevel: true,
+        typeofs: true,
+    }
+    input: {
+        if (A = console, "undefined" != typeof A)
+            for (var a = A, i = 0; i < 2; i++)
+                console.log(void 0 === A, void 0 === a),
+                A = void 0;
+    }
+    expect: {
+        if (A = console, "undefined" != typeof A)
+            for (var a = A, i = 0; i < 2; i++)
+                console.log(void 0 === A, (a, false)),
+                A = void 0;
+    }
+    expect_stdout: [
+        "false false",
+        "true false",
+    ]
+}
+
+reassign_for_in: {
+    options = {
+        comparisons: true,
+        conditionals: true,
+        passes: 2,
+        reduce_vars: true,
+        typeofs: true,
+    }
+    input: {
+        (A = console) && "undefined" != typeof A && function(a) {
+            for (var k in [ a = A, 42 ]) {
+                console.log(void 0 === A, void 0 === a);
+                A = void 0;
+            }
+        }();
+    }
+    expect: {
+        (A = console) && "undefined" != typeof A && function(a) {
+            for (var k in [ a = A, 42 ]) {
+                console.log(void 0 === A, (a, false));
+                A = void 0;
+            }
+        }();
+    }
+    expect_stdout: [
+        "false false",
+        "true false",
+    ]
+}
+
 reassign_iife: {
     options = {
         comparisons: true,
@@ -564,7 +660,7 @@ reassign_property: {
             console.log("FAIL 1");
         else {
             A.p = void 0;
-            while (console.log(void 0 === A ? "FAIL 2" : "PASS"));
+            console.log(void 0 === A ? "FAIL 2" : "PASS");
         }
     }
     expect: {
@@ -573,7 +669,7 @@ reassign_property: {
             console.log("FAIL 1");
         else {
             A.p = void 0;
-            while (console.log((A, false) ? "FAIL 2" : "PASS"));
+            console.log((A, false) ? "FAIL 2" : "PASS");
         }
     }
     expect_stdout: "PASS"