Address feedback

- Fix mangle implementation to work for all cases
- Update and add tests
- Document usage via the API

README.md

@@ -135,9 +135,12 @@ The available options are:
                                 --mangle-props
   --mangle-props                Mangle property names (default `0`). Set to 
                                 `true` or `1` to mangle all property names. Set
-                                to `1` to only mangle unquoted property names.
+                                to `2` to only mangle unquoted property names.
                                 Use the `keep_quoted_props` beautifier option to
-                                preserve the quotes around property names.
+                                preserve the quotes around property names and set
+                                the `properties` compressor option to `false` to
+                                prevent rewriting quoted properties with dot 
+                                notation.
   --mangle-regex                Only mangle property names matching the regex
   --name-cache                  File to hold mangled names mappings
   --pure-funcs                  List of functions that can be safely removed if
@@ -666,7 +669,8 @@ Other options:
 
 ##### mangleProperties options
 
- - `regex` — Pass a RegExp to only mangle certain names (maps to the `--mange-regex` CLI arguments option)
+ - `regex` — Pass a RegExp to only mangle certain names (maps to the `--mangle-regex` CLI arguments option)
+ - `ignore_quoted` – Only mangle unquoted property names (maps to the `--mangle-props 2` CLI arguments option)
 
 We could add more options to `UglifyJS.minify` — if you need additional
 functionality please suggest!

lib/propmangle.js

@@ -95,8 +95,7 @@ function mangle_properties(ast, options) {
         }
         else if (node instanceof AST_ObjectProperty) {
             // setter or getter, since KeyVal is handled above
-            if (!(ignore_quoted && node.key.quote))
-                add(node.key.name);
+            add(node.key.name);
         }
         else if (node instanceof AST_Dot) {
             if (this.parent() instanceof AST_Assign) {
@@ -105,7 +104,7 @@ function mangle_properties(ast, options) {
         }
         else if (node instanceof AST_Sub) {
             if (this.parent() instanceof AST_Assign) {
-                if (!(ignore_quoted && node.property.quote))
+                if (!ignore_quoted)
                     addStrings(node.property);
             }
         }
@@ -114,7 +113,8 @@ function mangle_properties(ast, options) {
     // step 2: transform the tree, renaming properties
     return ast.transform(new TreeTransformer(function(node){
         if (node instanceof AST_ObjectKeyVal) {
-            node.key = mangle(node.key);
+            if (!(ignore_quoted && node.quote))
+                node.key = mangle(node.key);
         }
         else if (node instanceof AST_ObjectProperty) {
             // setter or getter
@@ -124,7 +124,8 @@ function mangle_properties(ast, options) {
             node.property = mangle(node.property);
         }
         else if (node instanceof AST_Sub) {
-            node.property = mangleStrings(node.property);
+            if (!ignore_quoted)
+                node.property = mangleStrings(node.property);
         }
         // else if (node instanceof AST_String) {
         //     if (should_mangle(node.value)) {

test/compress/properties.js

@@ -92,15 +92,34 @@ mangle_properties: {
 mangle_unquoted_properties: {
     mangle_props = {
         ignore_quoted: true
-    };
+    }
+    beautify = {
+        beautify: false,
+        quote_style: 3,
+        keep_quoted_props: true,
+    }
     input: {
-        a["foo"] = "bar";
-        a.color = "red";
-        x = {"bar": 10};
+        function f1() {
+            a["foo"] = "bar";
+            a.color = "red";
+            x = {"bar": 10};
+        }
+        function f2() {
+            a.foo = "bar";
+            a['color'] = "red";
+            x = {bar: 10};
+        }
     }
     expect: {
-        a["foo"] = "bar";
-        a.a = "red";
-        x = {"bar": 10};
+        function f1() {
+            a["foo"] = "bar";
+            a.a = "red";
+            x = {"bar": 10};
+        }
+        function f2() {
+            a.b = "bar";
+            a['color'] = "red";
+            x = {c: 10};
+        }
     }
 }

test/mocha/minify.js

@@ -38,4 +38,25 @@ describe("minify", function() {
             assert.strictEqual(result.code, 'var foo={x:1,y:2,z:3};');
         });
     });
+
+    describe("mangleProperties", function() {
+        it("Shouldn't mangle quoted properties", function() {
+            var js = 'a["foo"] = "bar"; a.color = "red"; x = {"bar": 10};';
+            var result = Uglify.minify(js, {
+                fromString: true,
+                compress: {
+                    properties: false
+                },
+                mangleProperties: {
+                    ignore_quoted: true
+                },
+                output: {
+                    keep_quoted_props: true,
+                    quote_style: 3
+                }
+            });
+            assert.strictEqual(result.code,
+                    'a["foo"]="bar",a.a="red",x={"bar":10};');
+        });
+    });
 });

test/run-tests.js

@@ -106,7 +106,11 @@ function run_compress_tests() {
                 expect = test.expect_exact;
             }
             var input = as_toplevel(test.input);
-            var input_code = make_code(test.input, { beautify: true });
+            var input_code = make_code(test.input, {
+                beautify: true,
+                quote_style: 3,
+                keep_quoted_props: true
+            });
             if (test.mangle_props) {
                 input = U.mangle_properties(input, test.mangle_props);
             }