v3.6.9

fixes #3578

.github/workflows/ci.yml

@@ -14,6 +14,10 @@ jobs:
       TYPE: ${{ matrix.script }}
     steps:
       - uses: actions/checkout@v1
+      - uses: actions/cache@v1
+        with:
+          path: tmp
+          key: tmp ${{ matrix.script }}
       - shell: bash
         run: |
           git clone --branch v1.5.2 --depth 1 https://github.com/jasongin/nvs.git ~/.nvs

lib/compress.js

@@ -1235,7 +1235,7 @@ merge(Compressor.prototype, {
                     var lvalues = get_lvalues(candidate);
                     var lhs_local = is_lhs_local(lhs);
                     if (!side_effects) side_effects = value_has_side_effects(candidate);
-                    var replace_all = replace_all_symbols();
+                    var replace_all = replace_all_symbols(candidate);
                     var may_throw = candidate.may_throw(compressor) ? in_try ? function(node) {
                         return node.has_side_effects(compressor);
                     } : side_effects_external : return_false;
@@ -1283,6 +1283,7 @@ merge(Compressor.prototype, {
                             }
                             branch.expression = branch.expression.transform(scanner);
                             if (!replace_all) break;
+                            scan_rhs = false;
                         }
                     }
                     abort = true;
@@ -1312,6 +1313,7 @@ merge(Compressor.prototype, {
 
             function in_conditional(node, parent) {
                 if (parent instanceof AST_Binary) return lazy_op[parent.operator] && parent.left !== node;
+                if (parent instanceof AST_Case) return parent.expression !== node;
                 if (parent instanceof AST_Conditional) return parent.condition !== node;
                 return parent instanceof AST_If && parent.condition !== node;
             }
@@ -1477,19 +1479,43 @@ merge(Compressor.prototype, {
                 if (parent instanceof AST_Call) return node;
                 if (parent instanceof AST_Case) return node;
                 if (parent instanceof AST_Conditional) return node;
-                if (parent instanceof AST_Definitions) return find_stop(parent, level + 1);
+                if (parent instanceof AST_Definitions) return find_stop_unused(parent, level + 1);
                 if (parent instanceof AST_Exit) return node;
                 if (parent instanceof AST_If) return node;
                 if (parent instanceof AST_IterationStatement) return node;
                 if (parent instanceof AST_PropAccess) return node;
-                if (parent instanceof AST_Sequence) return find_stop(parent, level + 1);
-                if (parent instanceof AST_SimpleStatement) return find_stop(parent, level + 1);
+                if (parent instanceof AST_Sequence) {
+                    return (parent.tail_node() === node ? find_stop : find_stop_unused)(parent, level + 1);
+                }
+                if (parent instanceof AST_SimpleStatement) return find_stop_unused(parent, level + 1);
                 if (parent instanceof AST_Switch) return node;
                 if (parent instanceof AST_Unary) return node;
                 if (parent instanceof AST_VarDef) return node;
                 return null;
             }
 
+            function find_stop_unused(node, level) {
+                var parent = scanner.parent(level);
+                if (is_last_node(node, parent)) return node;
+                if (in_conditional(node, parent)) return node;
+                if (parent instanceof AST_Assign) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Binary) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Call) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Case) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Conditional) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Definitions) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Exit) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_If) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_IterationStatement) return node;
+                if (parent instanceof AST_PropAccess) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Sequence) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_SimpleStatement) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Switch) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_Unary) return find_stop_unused(parent, level + 1);
+                if (parent instanceof AST_VarDef) return find_stop_unused(parent, level + 1);
+                return null;
+            }
+
             function mangleable_var(var_def) {
                 var value = var_def.value;
                 if (!(value instanceof AST_SymbolRef)) return;
@@ -1656,7 +1682,8 @@ merge(Compressor.prototype, {
                 return get_rvalue(expr).has_side_effects(compressor);
             }
 
-            function replace_all_symbols() {
+            function replace_all_symbols(expr) {
+                if (expr instanceof AST_Unary) return false;
                 if (side_effects) return false;
                 if (value_def) return true;
                 if (lhs instanceof AST_SymbolRef) {
@@ -2881,6 +2908,7 @@ merge(Compressor.prototype, {
             if (!non_converting_binary[this.operator]) depth++;
             var left = this.left._eval(compressor, cached, depth);
             if (left === this.left) return this;
+            if (this.operator == (left ? "||" : "&&")) return left;
             var right = this.right._eval(compressor, cached, depth);
             if (right === this.right) return this;
             var result;
@@ -3049,7 +3077,10 @@ merge(Compressor.prototype, {
                         cached.push(node);
                     });
                 });
-                return stat.value ? stat.value._eval(compressor, cached, depth) : undefined;
+                if (!stat.value) return undefined;
+                var val = stat.value._eval(compressor, cached, depth);
+                if (val === stat.value) return this;
+                return val;
             } else if (compressor.option("unsafe") && exp instanceof AST_PropAccess) {
                 var key = exp.property;
                 if (key instanceof AST_Node) {
@@ -6512,23 +6543,30 @@ merge(Compressor.prototype, {
                     }
                 }
             } else if (self.left instanceof AST_SymbolRef) {
+                if (self.left.is_immutable()) return strip_assignment();
                 var def = self.left.definition();
-                if (def.scope === compressor.find_parent(AST_Lambda)) {
-                    if (self.left.is_immutable()) return strip_assignment();
-                    var level = 0, node, parent = self;
-                    do {
-                        node = parent;
-                        parent = compressor.parent(level++);
-                        if (parent instanceof AST_Exit) {
-                            if (in_try(level, parent)) break;
-                            if (is_reachable(def.scope, [ def ])) break;
-                            def.fixed = false;
-                            return strip_assignment();
-                        }
-                    } while (parent instanceof AST_Binary && parent.right === node
-                        || parent instanceof AST_Sequence && parent.tail_node() === node
-                        || parent instanceof AST_UnaryPrefix);
-                }
+                var scope = def.scope.resolve();
+                var local = scope === compressor.find_parent(AST_Lambda);
+                var level = 0, node, parent = self;
+                do {
+                    node = parent;
+                    parent = compressor.parent(level++);
+                    if (parent instanceof AST_Assign) {
+                        if (!(parent.left instanceof AST_SymbolRef)) continue;
+                        if (parent.left.definition() !== def) continue;
+                        if (in_try(level, parent)) break;
+                        def.fixed = false;
+                        return strip_assignment();
+                    } else if (parent instanceof AST_Exit) {
+                        if (!local) break;
+                        if (in_try(level, parent)) break;
+                        if (is_reachable(scope, [ def ])) break;
+                        def.fixed = false;
+                        return strip_assignment();
+                    }
+                } while (parent instanceof AST_Binary && parent.right === node
+                    || parent instanceof AST_Sequence && parent.tail_node() === node
+                    || parent instanceof AST_UnaryPrefix);
             }
         }
         self = self.lift_sequences(compressor);
@@ -6568,9 +6606,9 @@ merge(Compressor.prototype, {
             self.right = make_node(AST_Null, right);
             var may_throw = node.may_throw(compressor);
             self.right = right;
-            var scope = self.left.definition().scope;
             var parent;
-            while ((parent = compressor.parent(level++)) !== scope) {
+            while (parent = compressor.parent(level++)) {
+                if (parent === scope) return false;
                 if (parent instanceof AST_Try) {
                     if (parent.bfinally) return true;
                     if (may_throw && parent.bcatch) return true;
@@ -6637,7 +6675,7 @@ merge(Compressor.prototype, {
                 && alt_tail instanceof AST_Assign
                 && seq_tail.operator == alt_tail.operator
                 && seq_tail.left.equivalent_to(alt_tail.left)
-                && (is_eq && !seq_tail.left.has_side_effects(compressor)
+                && (is_eq && seq_tail.left instanceof AST_SymbolRef
                     || !condition.has_side_effects(compressor)
                         && can_shift_lhs_of_tail(consequent)
                         && can_shift_lhs_of_tail(alternative))) {
@@ -6806,16 +6844,9 @@ merge(Compressor.prototype, {
         }
 
         function can_shift_lhs_of_tail(node) {
-            if (node === node.tail_node()) return true;
-            var exprs = node.expressions;
-            for (var i = exprs.length - 1; --i >= 0;) {
-                var expr = exprs[i];
-                if (!(expr instanceof AST_Assign) && expr.has_side_effects(compressor)
-                    || expr.operator != "="
-                    || expr.left.has_side_effects(compressor)
-                    || expr.right.has_side_effects(compressor)) return false;
-            }
-            return true;
+            return node === node.tail_node() || all(node.expressions.slice(0, -1), function(expr) {
+                return !expr.has_side_effects(compressor);
+            });
         }
 
         function pop_lhs(node) {

package.json

@@ -3,7 +3,7 @@
   "description": "JavaScript parser, mangler/compressor and beautifier toolkit",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.6.7",
+  "version": "3.6.9",
   "engines": {
     "node": ">=0.8.0"
   },

test/compress/collapse_vars.js

@@ -6387,3 +6387,84 @@ issue_3562: {
     }
     expect_stdout: "PASS PASS"
 }
+
+dot_throw_assign_sequence: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a = "FAIL";
+        try {
+            var b;
+            b[0] = (a = "PASS", 0);
+            a = 1 + a;
+        } catch (c) {
+        }
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL";
+        try {
+            var b;
+            b[0] = (a = "PASS", 0);
+            a = 1 + a;
+        } catch (c) {
+        }
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}
+
+call_assign_order: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var a, b = 1, c = 0, log = console.log;
+        (function() {
+            a = b = "PASS";
+        })((b = "FAIL", c++));
+        log(a, b);
+    }
+    expect: {
+        var a, b = 1, c = 0, log = console.log;
+        (function() {
+            a = b = "PASS";
+        })((b = "FAIL", c++));
+        log(a, b);
+    }
+    expect_stdout: "PASS PASS"
+}
+
+issue_3573: {
+    options = {
+        collapse_vars: true,
+    }
+    input: {
+        var c = 0;
+        (function(b) {
+            while (--b) {
+                b = NaN;
+                switch (0 / this < 0) {
+                  case c++, false:
+                  case c++, NaN:
+                }
+            }
+        })(3);
+        console.log(c);
+    }
+    expect: {
+        var c = 0;
+        (function(b) {
+            while (--b) {
+                b = NaN;
+                switch (0 / this < 0) {
+                  case c++, false:
+                  case c++, NaN:
+                }
+            }
+        })(3);
+        console.log(c);
+    }
+    expect_stdout: "1"
+}

test/compress/conditionals.js

@@ -1489,3 +1489,29 @@ angularjs_chain: {
         }
     }
 }
+
+issue_3576: {
+    options = {
+        conditionals: true,
+        evaluate: true,
+        pure_getters: "strict",
+        reduce_vars: true,
+    }
+    input: {
+        var c = "FAIL";
+        (function(a) {
+            (a = -1) ? (a && (a.a = 0)) : (a && (a.a = 0));
+            a && a[c = "PASS"]++;
+        })();
+        console.log(c);
+    }
+    expect: {
+        var c = "FAIL";
+        (function(a) {
+            a = -1, a, a.a = 0;
+            a, a[c = "PASS"]++;
+        })();
+        console.log(c);
+    }
+    expect_stdout: "PASS"
+}

test/compress/dead-code.js

@@ -1064,3 +1064,68 @@ issue_3552: {
     }
     expect_stdout: "PASS"
 }
+
+unreachable_assign: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        console.log(A = "P" + (A = "A" + (B = "S" + (A = B = "S"))), A, B);
+    }
+    expect: {
+        console.log(A = "P" + "A" + (B = "S" + "S"), A, B);
+    }
+    expect_stdout: "PASS PASS SS"
+}
+
+catch_return_assign: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        console.log(function() {
+            try {
+                throw "FAIL";
+            } catch (e) {
+                return e = "PASS";
+            }
+        }());
+    }
+    expect: {
+        console.log(function() {
+            try {
+                throw "FAIL";
+            } catch (e) {
+                return "PASS";
+            }
+        }());
+    }
+    expect_stdout: "PASS"
+}
+
+issue_3578: {
+    options = {
+        dead_code: true,
+    }
+    input: {
+        var a = "FAIL", b, c;
+        try {
+            b = c.p = b = 0;
+        } catch (e) {
+            b += 42;
+            b && (a = "PASS");
+        }
+        console.log(a);
+    }
+    expect: {
+        var a = "FAIL", b, c;
+        try {
+            b = c.p = b = 0;
+        } catch (e) {
+            b += 42;
+            b && (a = "PASS");
+        }
+        console.log(a);
+    }
+    expect_stdout: "PASS"
+}

test/compress/evaluate.js

@@ -1876,3 +1876,27 @@ issue_3558: {
     }
     expect_stdout: "1 0"
 }
+
+issue_3568: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        toplevel: true,
+        unsafe: true,
+    }
+    input: {
+        var a = 0;
+        function f(b) {
+            return b && b.p;
+        }
+        console.log(f(++a + f()));
+    }
+    expect: {
+        var a = 0;
+        function f(b) {
+            return b && b.p;
+        }
+        console.log(NaN);
+    }
+    expect_stdout: "NaN"
+}