Merge pull request #1982 from alexlamsl/harmony-v3.0.10

Merging from master for 3.0.10

README.md

@@ -298,27 +298,64 @@ like this:
 var UglifyJS = require("uglify-es");
 ```
 
-There is a single high level minification function, `minify(files, options)`, which will
+There is a single high level minification function, `minify(code, options)`, which will
 performs all the steps in a configurable manner.
 Example:
 ```javascript
-var result = UglifyJS.minify("var b = function() {};");
+var code = "function add(first, second) { return first + second; }";
-console.log(result.code);  // minified output
+var result = UglifyJS.minify(code);
-console.log(result.error); // runtime error
+console.log(result.error); // runtime error, or `undefined` if no error
+console.log(result.code);  // minified output: function add(n,d){return n+d}
 ```
 
 You can also compress multiple files:
 ```javascript
-var result = UglifyJS.minify({
+var code = {
-    "file1.js": "var a = function() {};",
+    "file1.js": "function add(first, second) { return first + second; }",
-    "file2.js": "var b = function() {};"
+    "file2.js": "console.log(add(1 + 2, 3 + 4));"
-});
+};
-console.log(result.code);
+var result = UglifyJS.minify(code);
+console.log(result.code);  // function add(d,n){return d+n}console.log(add(3,7));
+```
+
+The `toplevel` option:
+```javascript
+var code = {
+    "file1.js": "function add(first, second) { return first + second; }",
+    "file2.js": "console.log(add(1 + 2, 3 + 4));"
+};
+var options = { toplevel: true };
+var result = UglifyJS.minify(code, options);
+console.log(result.code);  // console.log(function(n,o){return n+o}(3,7));
+```
+
+To produce warnings:
+```javascript
+var code = "function f(){ var u; return 2 + 3; }";
+var options = { warnings: true };
+var result = UglifyJS.minify(code, options);
+console.log(result.error);    // runtime error, `undefined` in this case
+console.log(result.warnings); // [ 'Dropping unused variable u [0:1,18]' ]
+console.log(result.code);     // function f(){return 5}
+```
+
+An error example:
+```javascript
+var result = UglifyJS.minify({"foo.js" : "if (0) else console.log(1);"});
+console.log(JSON.stringify(result.error));
+// {"message":"Unexpected token: keyword (else)","filename":"foo.js","line":1,"col":7,"pos":7}
+```
+Note: unlike `uglify-js@2.x`, the `3.x` API does not throw errors. To 
+achieve a similar effect one could do the following:
+```javascript
+var result = UglifyJS.minify(code, options);
+if (result.error) throw result.error;
 ```
 
 ## Minify options
 
-- `warnings` (default `false`) — pass `true` to display compressor warnings.
+- `warnings` (default `false`) — pass `true` to return compressor warnings 
+  in `result.warnings`. Use the value `"verbose"` for more detailed warnings.
 
 - `parse` (default `{}`) — pass an object if you wish to specify some
   additional [parse options](#parse-options).
@@ -344,7 +381,7 @@ console.log(result.code);
 
 - `ie8` (default `false`) - set to `true` to support IE8.
 
-## Minify option structure
+## Minify options structure
 
 ```javascript
 {
@@ -459,6 +496,9 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 - `unsafe_proto` (default: false) -- optimize expressions like
   `Array.prototype.slice.call(a)` into `[].slice.call(a)`
 
+- `unsafe_regexp` (default: false) -- enable substitutions of variables with
+  `RegExp` values the same way as if they are constants.
+
 - `conditionals` -- apply optimizations for `if`-s and conditional
   expressions
 
@@ -496,8 +536,8 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
 - `cascade` -- small optimization for sequences, transform `x, x` into `x`
   and `x = something(), x` into `x = something()`
 
-- `collapse_vars` -- Collapse single-use `var` and `const` definitions
+- `collapse_vars` -- Collapse single-use non-constant variables - side 
-  when possible.
+  effects permitting.
 
 - `reduce_vars` -- Improve optimization on variables assigned with and
   used as constant values.
@@ -550,9 +590,9 @@ If you're using the `X-SourceMap` header instead, you can just omit `sourceMap.u
   being compressed into `1/0`, which may cause performance issues on Chrome.
 
 - `side_effects` -- default `true`. Pass `false` to disable potentially dropping
-functions marked as "pure".  A function call is marked as "pure" if a comment
+  functions marked as "pure".  A function call is marked as "pure" if a comment
-annotation `/*@__PURE__*/` or `/*#__PURE__*/` immediately precedes the call. For
+  annotation `/*@__PURE__*/` or `/*#__PURE__*/` immediately precedes the call. For
-example: `/*@__PURE__*/foo()`;
+  example: `/*@__PURE__*/foo();`
 
 ## Mangle options
 
@@ -722,8 +762,8 @@ Another way of doing that is to declare your globals as constants in a
 separate file and include it into the build.  For example you can have a
 `build/defines.js` file with the following:
 ```javascript
-const DEBUG = false;
+var DEBUG = false;
-const PRODUCTION = true;
+var PRODUCTION = true;
 // etc.
 ```
 

lib/compress.js

@@ -84,6 +84,7 @@ function Compressor(options, false_by_default) {
         unsafe_comps  : false,
         unsafe_math   : false,
         unsafe_proto  : false,
+        unsafe_regexp : false,
         unused        : !false_by_default,
         warnings      : false,
     }, true);
@@ -545,11 +546,11 @@ merge(Compressor.prototype, {
         return lhs instanceof AST_SymbolRef && lhs.definition().orig[0] instanceof AST_SymbolLambda;
     }
 
-    function is_reference_const(ref) {
+    function is_ref_of(ref, type) {
         if (!(ref instanceof AST_SymbolRef)) return false;
         var orig = ref.definition().orig;
         for (var i = orig.length; --i >= 0;) {
-            if (orig[i] instanceof AST_SymbolConst) return true;
+            if (orig[i] instanceof type) return true;
         }
     }
 
@@ -828,7 +829,7 @@ merge(Compressor.prototype, {
                     }
                 } else {
                     var lhs = expr[expr instanceof AST_Assign ? "left" : "expression"];
-                    return !is_reference_const(lhs) && lhs;
+                    return !is_ref_of(lhs, AST_SymbolConst) && lhs;
                 }
             }
 
@@ -939,12 +940,12 @@ merge(Compressor.prototype, {
                     continue loop;
                   case stat instanceof AST_If:
                     if (stat.body instanceof AST_Return) {
+                        var value = stat.body.value;
                         //---
                         // pretty silly case, but:
                         // if (foo()) return; return; ==> foo(); return;
-                        if (((in_lambda && ret.length == 0)
+                        if ((in_lambda && ret.length == 0 || ret[0] instanceof AST_Return && !ret[0].value)
-                             || (ret[0] instanceof AST_Return && !ret[0].value))
+                            && !value && !stat.alternative) {
-                            && !stat.body.value && !stat.alternative) {
                             CHANGED = true;
                             var cond = make_node(AST_SimpleStatement, stat.condition, {
                                 body: stat.condition
@@ -954,7 +955,7 @@ merge(Compressor.prototype, {
                         }
                         //---
                         // if (foo()) return x; return y; ==> return foo() ? x : y;
-                        if (ret[0] instanceof AST_Return && stat.body.value && ret[0].value && !stat.alternative) {
+                        if (ret[0] instanceof AST_Return && value && ret[0].value && !stat.alternative) {
                             CHANGED = true;
                             stat = stat.clone();
                             stat.alternative = ret[0];
@@ -964,7 +965,7 @@ merge(Compressor.prototype, {
                         //---
                         // if (foo()) return x; [ return ; ] ==> return foo() ? x : undefined;
                         if (multiple_if_returns && (ret.length == 0 || ret[0] instanceof AST_Return)
-                            && stat.body.value && !stat.alternative && in_lambda) {
+                            && value && !stat.alternative && in_lambda) {
                             CHANGED = true;
                             stat = stat.clone();
                             stat.alternative = ret[0] || make_node(AST_Return, stat, {
@@ -974,8 +975,8 @@ merge(Compressor.prototype, {
                             continue loop;
                         }
                         //---
-                        // if (foo()) return; [ else x... ]; y... ==> if (!foo()) { x...; y... }
+                        // if (foo()) return [ void bar() ]; [ else x...; ] y... ==> if (!foo()) { x...; y... } else bar();
-                        if (!stat.body.value && in_lambda) {
+                        if (in_lambda && (!value || value instanceof AST_UnaryPrefix && value.operator == "void")) {
                             CHANGED = true;
                             stat = stat.clone();
                             stat.condition = stat.condition.negate(compressor);
@@ -984,11 +985,12 @@ merge(Compressor.prototype, {
                             stat.body = make_node(AST_BlockStatement, stat, {
                                 body: body
                             });
-                            stat.alternative = null;
+                            stat.alternative = value ? make_node(AST_SimpleStatement, value, {
+                                body: value.expression
+                            }) : null;
                             ret = funs.concat([ stat.transform(compressor) ]);
                             continue loop;
                         }
-
                         //---
                         // if (a) return b; if (c) return d; e; ==> return a ? b : c ? d : void e;
                         //
@@ -2056,7 +2058,7 @@ merge(Compressor.prototype, {
                     && node instanceof AST_Assign
                     && node.operator == "="
                     && node.left instanceof AST_SymbolRef
-                    && !is_reference_const(node.left)
+                    && !is_ref_of(node.left, AST_SymbolBlockDeclaration)
                     && scope === self) {
                     node.right.walk(tw);
                     return true;
@@ -3160,7 +3162,6 @@ merge(Compressor.prototype, {
                     // Symbol's argument is only used for debugging.
                     self.args = [];
                     return self;
-                    break;
                 }
             }
             else if (exp instanceof AST_Dot && exp.property == "toString" && self.args.length == 0) {
@@ -3343,7 +3344,7 @@ merge(Compressor.prototype, {
                     && (left.operator == "++" || left.operator == "--")) {
                     left = left.expression;
                 } else left = null;
-                if (!left || is_lhs_read_only(left) || is_reference_const(left)) {
+                if (!left || is_lhs_read_only(left) || is_ref_of(left, AST_SymbolConst)) {
                     expressions[++i] = cdr;
                     continue;
                 }
@@ -3912,7 +3913,7 @@ merge(Compressor.prototype, {
             if (fixed) {
                 if (d.should_replace === undefined) {
                     var init = fixed.evaluate(compressor);
-                    if (init !== fixed) {
+                    if (init !== fixed && (compressor.option("unsafe_regexp") || !(init instanceof RegExp))) {
                         init = make_node_from_constant(init, fixed);
                         var value_length = init.optimize(compressor).print_to_string().length;
                         var fn;

lib/parse.js

@@ -2411,7 +2411,8 @@ function parse($TEXT, options) {
                 unexpected(tmp);
             }
           case "name":
-            if (tmp.value === "yield" && S.input.has_directive("use strict") && !is_in_generator()) {
+            if (tmp.value == "yield" && !is_token(peek(), "punc", ":")
+                && S.input.has_directive("use strict") && !is_in_generator()) {
                 token_error(tmp, "Unexpected yield identifier inside strict mode");
             }
           case "string":

package.json

@@ -4,7 +4,7 @@
   "homepage": "https://github.com/mishoo/UglifyJS2/tree/harmony",
   "author": "Mihai Bazon <mihai.bazon@gmail.com> (http://lisperator.net/)",
   "license": "BSD-2-Clause",
-  "version": "3.0.8",
+  "version": "3.0.10",
   "engines": {
     "node": ">=0.8.0"
   },
@@ -40,5 +40,5 @@
   "scripts": {
     "test": "node test/run-tests.js"
   },
-  "keywords": ["uglify", "uglify-js", "minify", "minifier"]
+  "keywords": ["uglify", "uglify-js", "uglify-es", "minify", "minifier", "es5", "es6", "es2015"]
 }

test/compress/drop-unused.js

@@ -1253,3 +1253,30 @@ reassign_const: {
     }
     expect_stdout: true
 }
+
+issue_1968: {
+    options = {
+        unused: true,
+    }
+    input: {
+        function f(c) {
+            var a;
+            if (c) {
+                let b;
+                return (a = 2) + (b = 3);
+            }
+        }
+        console.log(f(1));
+    }
+    expect: {
+        function f(c) {
+            if (c) {
+                let b;
+                return 2 + (b = 3);
+            }
+        }
+        console.log(f(1));
+    }
+    expect_stdout: "5"
+    node_version: ">=6"
+}

test/compress/evaluate.js

@@ -1083,3 +1083,50 @@ Infinity_NaN_undefined_LHS: {
         "}",
     ]
 }
+
+issue_1964_1: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe_regexp: false,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var long_variable_name = /\s/;
+            return "a b c".split(long_variable_name)[1];
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            var long_variable_name = /\s/;
+            return "a b c".split(long_variable_name)[1];
+        }
+        console.log(f());
+    }
+    expect_stdout: "b"
+}
+
+issue_1964_2: {
+    options = {
+        evaluate: true,
+        reduce_vars: true,
+        unsafe_regexp: true,
+        unused: true,
+    }
+    input: {
+        function f() {
+            var long_variable_name = /\s/;
+            return "a b c".split(long_variable_name)[1];
+        }
+        console.log(f());
+    }
+    expect: {
+        function f() {
+            return "a b c".split(/\s/)[1];
+        }
+        console.log(f());
+    }
+    expect_stdout: "b"
+}

test/compress/if_return.js

@@ -302,3 +302,25 @@ issue_1437_conditionals: {
         }
     }
 }
+
+issue_512: {
+    options = {
+        conditionals: true,
+        if_return: true,
+    }
+    input: {
+        function a() {
+            if (b()) {
+                c();
+                return;
+            }
+            throw e;
+        }
+    }
+    expect: {
+        function a() {
+            if (!b()) throw e;
+            c();
+        }
+    }
+}

test/compress/yield.js

@@ -190,3 +190,12 @@ yield_sub: {
     }
     expect_exact: 'function*foo(){yield x["foo"];(yield x)["foo"];yield(yield obj.foo())["bar"]()}'
 }
+
+yield_as_ES5_property: {
+    input: {
+        "use strict";
+        console.log({yield: 42}.yield);
+    }
+    expect_exact: '"use strict";console.log({yield:42}.yield);'
+    expect_stdout: "42"
+}

test/mocha/cli.js

@@ -19,7 +19,9 @@ describe("bin/uglifyjs", function () {
             eval(stdout);
 
             assert.strictEqual(typeof WrappedUglifyJS, 'object');
-            assert.strictEqual(WrappedUglifyJS.minify("foo([true,,2+3]);").code, "foo([!0,,5]);");
+            var result = WrappedUglifyJS.minify("foo([true,,2+3]);");
+            assert.strictEqual(result.error, undefined);
+            assert.strictEqual(result.code, "foo([!0,,5]);");
 
             done();
         });

test/mocha/spidermonkey.js

@@ -15,7 +15,9 @@ describe("spidermonkey export/import sanity test", function() {
 
             eval(stdout);
             assert.strictEqual(typeof SpiderUglify, "object");
-            assert.strictEqual(SpiderUglify.minify("foo([true,,2+3]);").code, "foo([!0,,5]);");
+            var result = SpiderUglify.minify("foo([true,,2+3]);");
+            assert.strictEqual(result.error, undefined);
+            assert.strictEqual(result.code, "foo([!0,,5]);");
 
             done();
         });

test/mocha/yield.js

@@ -65,9 +65,9 @@ describe("Yield", function() {
         );
     });
 
-    it("Should not allow yield to be used as symbol, identifier or property outside generators in strict mode", function() {
+    it("Should not allow yield to be used as symbol, identifier or shorthand property outside generators in strict mode", function() {
         var tests = [
-            // Fail as as_symbol
+            // Fail in as_symbol
             '"use strict"; import yield from "bar";',
             '"use strict"; yield = 123;',
             '"use strict"; yield: "123";',
@@ -79,13 +79,12 @@ describe("Yield", function() {
             '"use strict"; var yield = "foo";',
             '"use strict"; class yield {}',
 
-            // Fail as maybe_assign
+            // Fail in maybe_assign
             '"use strict"; var foo = yield;',
             '"use strict"; var foo = bar = yield',
 
-            // Fail as as_property_name
+            // Fail in as_property_name
             '"use strict"; var foo = {yield};',
-            '"use strict"; var bar = {yield: "foo"};'
         ];
 
         var fail = function(e) {