v2.4.24

Fix #751

README.md

@@ -132,6 +132,7 @@ The available options are:
   --reserve-domprops            Make (most?) DOM properties reserved for
                                 --mangle-props
   --mangle-props                Mangle property names
+  --mangle-regex                Only mangle property names matching the regex
   --name-cache                  File to hold mangled names mappings
 ```
 
@@ -251,6 +252,10 @@ A default exclusion file is provided in `tools/domprops.json` which should
 cover most standard JS and DOM properties defined in various browsers.  Pass
 `--reserve-domprops` to read that in.
 
+You can also use a regular expression to define which property names should be
+mangled.  For example, `--mangle-regex="/^_/"` will only mangle property names
+that start with an underscore.
+
 When you compress multiple files using this option, in order for them to
 work together in the end we need to ensure somehow that one property gets
 mangled to the same name in all of them.  For this, pass `--name-cache

bin/uglifyjs

@@ -70,6 +70,7 @@ You need to pass an argument to this option to specify the name that your module
     .describe("reserved-file", "File containing reserved names")
     .describe("reserve-domprops", "Make (most?) DOM properties reserved for --mangle-props")
     .describe("mangle-props", "Mangle property names")
+    .describe("mangle-regex", "Only mangle property names matching the regex")
     .describe("name-cache", "File to hold mangled names mappings")
 
     .alias("p", "prefix")
@@ -191,6 +192,15 @@ function writeNameCache(key, cache) {
     return UglifyJS.writeNameCache(ARGS.name_cache, key, cache);
 }
 
+function extractRegex(str) {
+  if (/^\/.*\/[a-zA-Z]*$/.test(str)) {
+    var regex_pos = str.lastIndexOf("/");
+    return new RegExp(str.substr(1, regex_pos - 1), str.substr(regex_pos + 1));
+  } else {
+    throw new Error("Invalid regular expression: " + str);
+  }
+}
+
 if (ARGS.quotes === true) {
     ARGS.quotes = 3;
 }
@@ -217,9 +227,8 @@ if (BEAUTIFY)
 
 if (ARGS.comments != null) {
     if (/^\/.*\/[a-zA-Z]*$/.test(ARGS.comments)) {
-        var regex_pos = ARGS.comments.lastIndexOf("/");
         try {
-            OUTPUT_OPTIONS.comments = new RegExp(ARGS.comments.substr(1, regex_pos - 1), ARGS.comments.substr(regex_pos + 1));
+            OUTPUT_OPTIONS.comments = extractRegex(ARGS.comments);
         } catch (e) {
             print_error("ERROR: Invalid --comments: " + e.message);
         }
@@ -375,10 +384,20 @@ async.eachLimit(files, 1, function (file, cb) {
     if (ARGS.mangle_props || ARGS.name_cache) (function(){
         var reserved = RESERVED ? RESERVED.props : null;
         var cache = readNameCache("props");
+        var regex;
+
+        try {
+          regex = ARGS.mangle_regex ? extractRegex(ARGS.mangle_regex) : null;
+        } catch (e) {
+            print_error("ERROR: Invalid --mangle-regex: " + e.message);
+            process.exit(1);
+        }
+
         TOPLEVEL = UglifyJS.mangle_properties(TOPLEVEL, {
             reserved   : reserved,
             cache      : cache,
-            only_cache : !ARGS.mangle_props
+            only_cache : !ARGS.mangle_props,
+            regex      : regex
         });
         writeNameCache("props", cache);
     })();

lib/compress.js

@@ -2104,6 +2104,34 @@ merge(Compressor.prototype, {
             }
             break;
         }
+        if (compressor.option("conditionals")) {
+            if (self.operator == "&&") {
+                var ll = self.left.evaluate(compressor);
+                var rr = self.right.evaluate(compressor);
+                if (ll.length > 1) {
+                    if (ll[1]) {
+                        compressor.warn("Condition left of && always true [{file}:{line},{col}]", self.start);
+                        return rr[0];
+                    } else {
+                        compressor.warn("Condition left of && always false [{file}:{line},{col}]", self.start);
+                        return ll[0];
+                    }
+                }
+            }
+            else if (self.operator == "||") {
+                var ll = self.left.evaluate(compressor);
+                var rr = self.right.evaluate(compressor);
+                if (ll.length > 1) {
+                    if (ll[1]) {
+                        compressor.warn("Condition left of || always true [{file}:{line},{col}]", self.start);
+                        return ll[0];
+                    } else {
+                        compressor.warn("Condition left of || always false [{file}:{line},{col}]", self.start);
+                        return rr[0];
+                    }
+                }
+            }
+        }
         if (compressor.option("booleans") && compressor.in_boolean_context()) switch (self.operator) {
           case "&&":
             var ll = self.left.evaluate(compressor);
@@ -2155,7 +2183,7 @@ merge(Compressor.prototype, {
             }
             break;
         }
-        if (compressor.option("comparisons")) {
+        if (compressor.option("comparisons") && self.is_boolean()) {
             if (!(compressor.parent() instanceof AST_Binary)
                 || compressor.parent() instanceof AST_Assign) {
                 var negated = make_node(AST_UnaryPrefix, self, {
@@ -2230,10 +2258,11 @@ merge(Compressor.prototype, {
                 }
             }
         }
-        // x * (y * z)  ==>  x * y * z
+        // x && (y && z)  ==>  x && y && z
+        // x || (y || z)  ==>  x || y || z
         if (self.right instanceof AST_Binary
             && self.right.operator == self.operator
-            && (self.operator == "*" || self.operator == "&&" || self.operator == "||"))
+            && (self.operator == "&&" || self.operator == "||"))
         {
             self.left = make_node(AST_Binary, self.left, {
                 operator : self.operator,

lib/propmangle.js

@@ -64,7 +64,8 @@ function mangle_properties(ast, options) {
     options = defaults(options, {
         reserved : null,
         cache : null,
-        only_cache : false
+        only_cache : false,
+        regex : null
     });
 
     var reserved = options.reserved;
@@ -79,6 +80,8 @@ function mangle_properties(ast, options) {
         };
     }
 
+    var regex = options.regex;
+
     var names_to_mangle = [];
 
     // step 1: find candidates to mangle
@@ -149,6 +152,7 @@ function mangle_properties(ast, options) {
     }
 
     function should_mangle(name) {
+        if (regex && !regex.test(name)) return false;
         if (reserved.indexOf(name) >= 0) return false;
         return cache.props.has(name)
             || names_to_mangle.indexOf(name) >= 0;

package.json

@@ -4,7 +4,7 @@
   "homepage": "http://lisperator.net/uglifyjs",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD",
-  "version": "2.4.23",
+  "version": "2.4.24",
   "engines": {
     "node": ">=0.4.0"
   },

test/compress/conditionals.js

@@ -384,3 +384,163 @@ cond_8: {
         a = condition ? 1 : 0;
     }
 }
+
+conditional_and: {
+    options = {
+        conditionals: true,
+        evaluate    : true
+    };
+    input: {
+        var a;
+        // compress these
+
+        a = true     && condition;
+        a = 1        && console.log("a");
+        a = 2 * 3    && 2 * condition;
+        a = 5 == 5   && condition + 3;
+        a = "string" && 4 - condition;
+        a = 5 + ""   && condition / 5;
+        a = -4.5     && 6 << condition;
+        a = 6        && 7;
+
+        a = false     && condition;
+        a = NaN       && console.log("b");
+        a = 0         && console.log("c");
+        a = undefined && 2 * condition;
+        a = null      && condition + 3;
+        a = 2 * 3 - 6 && 4 - condition;
+        a = 10 == 7   && condition / 5;
+        a = !"string" && 6 % condition;
+        a = 0         && 7;
+
+        // don't compress these
+
+        a = condition        && true;
+        a = console.log("a") && 2;
+        a = 4 - condition    && "string";
+        a = 6 << condition   && -4.5;
+
+        a = condition        && false;
+        a = console.log("b") && NaN;
+        a = console.log("c") && 0;
+        a = 2 * condition    && undefined;
+        a = condition + 3    && null;
+
+    }
+    expect: {
+        var a;
+
+        a = condition;
+        a = console.log("a");
+        a = 2 * condition;
+        a = condition + 3;
+        a = 4 - condition;
+        a = condition / 5;
+        a = 6 << condition;
+        a = 7;
+
+        a = false;
+        a = NaN;
+        a = 0;
+        a = void 0;
+        a = null;
+        a = 0;
+        a = false;
+        a = false;
+        a = 0;
+
+        a = condition        && true;
+        a = console.log("a") && 2;
+        a = 4 - condition    && "string";
+        a = 6 << condition   && -4.5;
+
+        a = condition        && false;
+        a = console.log("b") && NaN;
+        a = console.log("c") && 0;
+        a = 2 * condition    && void 0;
+        a = condition + 3    && null;
+    }
+}
+
+conditional_or: {
+    options = {
+        conditionals: true,
+        evaluate    : true
+    };
+    input: {
+        var a;
+        // compress these
+
+        a = true     || condition;
+        a = 1        || console.log("a");
+        a = 2 * 3    || 2 * condition;
+        a = 5 == 5   || condition + 3;
+        a = "string" || 4 - condition;
+        a = 5 + ""   || condition / 5;
+        a = -4.5     || 6 << condition;
+        a = 6        || 7;
+
+        a = false     || condition;
+        a = 0         || console.log("b");
+        a = NaN       || console.log("c");
+        a = undefined || 2 * condition;
+        a = null      || condition + 3;
+        a = 2 * 3 - 6 || 4 - condition;
+        a = 10 == 7   || condition / 5;
+        a = !"string" || 6 % condition;
+        a = null      || 7;
+
+        a = console.log(undefined && condition || null);
+        a = console.log(undefined || condition && null);
+
+        // don't compress these
+
+        a = condition        || true;
+        a = console.log("a") || 2;
+        a = 4 - condition    || "string";
+        a = 6 << condition   || -4.5;
+
+        a = condition        || false;
+        a = console.log("b") || NaN;
+        a = console.log("c") || 0;
+        a = 2 * condition    || undefined;
+        a = condition + 3    || null;
+
+    }
+    expect: {
+        var a;
+
+        a = true;
+        a = 1;
+        a = 6;
+        a = true;
+        a = "string";
+        a = "5";
+        a = -4.5;
+        a = 6;
+
+        a = condition;
+        a = console.log("b");
+        a = console.log("c");
+        a = 2 * condition;
+        a = condition + 3;
+        a = 4 - condition;
+        a = condition / 5;
+        a = 6 % condition;
+        a = 7;
+
+        a = console.log(null);
+        a = console.log(condition && null);
+
+        a = condition        || true;
+        a = console.log("a") || 2;
+        a = 4 - condition    || "string";
+        a = 6 << condition   || -4.5;
+
+        a = condition        || false;
+        a = console.log("b") || NaN;
+        a = console.log("c") || 0;
+        a = 2 * condition    || void 0;
+        a = condition + 3    || null;
+    }
+}

test/compress/issue-751.js

@@ -0,0 +1,29 @@
+negate_booleans_1: {
+    options = {
+        comparisons: true
+    };
+    input: {
+        var a = !a || !b || !c || !d || !e || !f;
+    }
+    expect: {
+        var a = !(a && b && c && d && e && f);
+    }
+}
+
+negate_booleans_2: {
+    options = {
+        comparisons: true
+    };
+    input: {
+        var match = !x &&       // should not touch this one
+            (!z || c) &&
+            (!k || d) &&
+            the_stuff();
+    }
+    expect: {
+        var match = !x &&
+            (!z || c) &&
+            (!k || d) &&
+            the_stuff();
+    }
+}