flow like the river

VISUALIZACION/node_modules/htmlnano/lib/modules/removeRedundantAttributes.js

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+'use strict';
+
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+exports.default = removeRedundantAttributes;
+var redundantAttributes = {
+    'form': {
+        'method': 'get'
+    },
+
+    'input': {
+        'type': 'text'
+    },
+
+    'button': {
+        'type': 'submit'
+    },
+
+    'script': {
+        'language': 'javascript',
+        'type': 'text/javascript',
+        // Remove attribute if the function returns false
+        'charset': function charset(node) {
+            // The charset attribute only really makes sense on “external” SCRIPT elements:
+            // http://perfectionkills.com/optimizing-html/#8_script_charset
+            return node.attrs && !node.attrs.src;
+        }
+    },
+
+    'style': {
+        'media': 'all',
+        'type': 'text/css'
+    },
+
+    'link': {
+        'media': 'all'
+    }
+};
+
+/** Removes redundant attributes */
+function removeRedundantAttributes(tree) {
+    var tags = Object.keys(redundantAttributes);
+    var tagMatchRegExp = new RegExp('^(' + tags.join('|') + ')$');
+    tree.match({ tag: tagMatchRegExp }, function (node) {
+        var tagRedundantAttributes = redundantAttributes[node.tag];
+        node.attrs = node.attrs || {};
+        var _iteratorNormalCompletion = true;
+        var _didIteratorError = false;
+        var _iteratorError = undefined;
+
+        try {
+            for (var _iterator = Object.keys(tagRedundantAttributes)[Symbol.iterator](), _step; !(_iteratorNormalCompletion = (_step = _iterator.next()).done); _iteratorNormalCompletion = true) {
+                var redundantAttributeName = _step.value;
+
+                var tagRedundantAttributeValue = tagRedundantAttributes[redundantAttributeName];
+                var isRemove = false;
+                if (typeof tagRedundantAttributeValue === 'function') {
+                    isRemove = tagRedundantAttributeValue(node);
+                } else if (node.attrs[redundantAttributeName] === tagRedundantAttributeValue) {
+                    isRemove = true;
+                }
+
+                if (isRemove) {
+                    delete node.attrs[redundantAttributeName];
+                }
+            }
+        } catch (err) {
+            _didIteratorError = true;
+            _iteratorError = err;
+        } finally {
+            try {
+                if (!_iteratorNormalCompletion && _iterator.return) {
+                    _iterator.return();
+                }
+            } finally {
+                if (_didIteratorError) {
+                    throw _iteratorError;
+                }
+            }
+        }
+
+        return node;
+    });
+
+    return tree;
+}