Refactor basic plugins with visitor api (#1518)

- cleanupAttrs
- convertEllipseToCircle
- removeDesc
- removeDoctype
- removeEmptyText
- removeMetadata
- removeRasterImages
- removeScriptElement
- removeStyleElement
- removeTitle
- removeXMLProcInst

plugins/cleanupAttrs.js

@@ -1,52 +1,48 @@
 'use strict';
 
-exports.type = 'perItem';
-
+exports.type = 'visitor';
 exports.active = true;
-
 exports.description =
   'cleanups attributes from newlines, trailing and repeating spaces';
 
-exports.params = {
-  newlines: true,
-  trim: true,
-  spaces: true,
-};
-
-var regNewlinesNeedSpace = /(\S)\r?\n(\S)/g,
-  regNewlines = /\r?\n/g,
-  regSpaces = /\s{2,}/g;
+const regNewlinesNeedSpace = /(\S)\r?\n(\S)/g;
+const regNewlines = /\r?\n/g;
+const regSpaces = /\s{2,}/g;
 
 /**
  * Cleanup attributes values from newlines, trailing and repeating spaces.
  *
- * @param {Object} item current iteration item
- * @param {Object} params plugin params
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Kir Belevich
  */
-exports.fn = function (item, params) {
-  if (item.type === 'element') {
-    for (const name of Object.keys(item.attributes)) {
-      if (params.newlines) {
-        // new line which requires a space instead of themselve
-        item.attributes[name] = item.attributes[name].replace(
-          regNewlinesNeedSpace,
-          (match, p1, p2) => p1 + ' ' + p2
-        );
-
-        // simple new line
-        item.attributes[name] = item.attributes[name].replace(regNewlines, '');
-      }
-
-      if (params.trim) {
-        item.attributes[name] = item.attributes[name].trim();
-      }
-
-      if (params.spaces) {
-        item.attributes[name] = item.attributes[name].replace(regSpaces, ' ');
-      }
-    }
-  }
+exports.fn = (root, params) => {
+  const { newlines = true, trim = true, spaces = true } = params;
+  return {
+    element: {
+      enter: (node) => {
+        for (const name of Object.keys(node.attributes)) {
+          if (newlines) {
+            // new line which requires a space instead of themselve
+            node.attributes[name] = node.attributes[name].replace(
+              regNewlinesNeedSpace,
+              (match, p1, p2) => p1 + ' ' + p2
+            );
+            // simple new line
+            node.attributes[name] = node.attributes[name].replace(
+              regNewlines,
+              ''
+            );
+          }
+          if (trim) {
+            node.attributes[name] = node.attributes[name].trim();
+          }
+          if (spaces) {
+            node.attributes[name] = node.attributes[name].replace(
+              regSpaces,
+              ' '
+            );
+          }
+        }
+      },
+    },
+  };
 };

plugins/convertEllipseToCircle.js

@@ -1,9 +1,7 @@
 'use strict';
 
-exports.type = 'perItem';
-
+exports.type = 'visitor';
 exports.active = true;
-
 exports.description = 'converts non-eccentric <ellipse>s to <circle>s';
 
 /**
@@ -11,26 +9,28 @@ exports.description = 'converts non-eccentric <ellipse>s to <circle>s';
  *
  * @see https://www.w3.org/TR/SVG11/shapes.html
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Taylor Hunt
  */
-exports.fn = function (item) {
-  if (item.isElem('ellipse')) {
-    const rx = item.attributes.rx || 0;
-    const ry = item.attributes.ry || 0;
-
-    if (
-      rx === ry ||
-      rx === 'auto' ||
-      ry === 'auto' // SVG2
-    ) {
-      var radius = rx !== 'auto' ? rx : ry;
-      item.renameElem('circle');
-      delete item.attributes.rx;
-      delete item.attributes.ry;
-      item.attributes.r = radius;
-    }
-  }
+exports.fn = () => {
+  return {
+    element: {
+      enter: (node) => {
+        if (node.name === 'ellipse') {
+          const rx = node.attributes.rx || 0;
+          const ry = node.attributes.ry || 0;
+          if (
+            rx === ry ||
+            rx === 'auto' ||
+            ry === 'auto' // SVG2
+          ) {
+            node.name = 'circle';
+            const radius = rx === 'auto' ? ry : rx;
+            delete node.attributes.rx;
+            delete node.attributes.ry;
+            node.attributes.r = radius;
+          }
+        }
+      },
+    },
+  };
 };

plugins/removeDesc.js

@@ -1,16 +1,12 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = true;
-
-exports.params = {
-  removeAny: true,
-};
-
 exports.description = 'removes <desc>';
 
-var standardDescs = /^(Created with|Created using)/;
+const standardDescs = /^(Created with|Created using)/;
 
 /**
  * Removes <desc>.
@@ -19,19 +15,24 @@ var standardDescs = /^(Created with|Created using)/;
  *
  * https://developer.mozilla.org/en-US/docs/Web/SVG/Element/desc
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Daniel Wabyick
  */
-exports.fn = function (item, params) {
-  return (
-    !item.isElem('desc') ||
-    !(
-      params.removeAny ||
-      item.children.length === 0 ||
-      (item.children[0].type === 'text' &&
-        standardDescs.test(item.children[0].value))
-    )
-  );
+exports.fn = (root, params) => {
+  const { removeAny = true } = params;
+  return {
+    element: {
+      enter: (node, parentNode) => {
+        if (node.name === 'desc') {
+          if (
+            removeAny ||
+            node.children.length === 0 ||
+            (node.children[0].type === 'text' &&
+              standardDescs.test(node.children[0].value))
+          ) {
+            detachNodeFromParent(node, parentNode);
+          }
+        }
+      },
+    },
+  };
 };

plugins/removeDoctype.js

@@ -1,9 +1,9 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = true;
-
 exports.description = 'removes doctype declaration';
 
 /**
@@ -26,13 +26,14 @@ exports.description = 'removes doctype declaration';
  *     <!-- an internal subset can be embedded here -->
  * ]>
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Kir Belevich
  */
-exports.fn = function (item) {
-  if (item.type === 'doctype') {
-    return false;
-  }
+exports.fn = () => {
+  return {
+    doctype: {
+      enter: (node, parentNode) => {
+        detachNodeFromParent(node, parentNode);
+      },
+    },
+  };
 };

plugins/removeEmptyText.js

@@ -1,17 +1,11 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = true;
-
 exports.description = 'removes empty <text> elements';
 
-exports.params = {
-  text: true,
-  tspan: true,
-  tref: true,
-};
-
 /**
  * Remove empty Text elements.
  *
@@ -27,31 +21,30 @@ exports.params = {
  * Remove tref with empty xlink:href attribute:
  * <tref xlink:href=""/>
  *
- * @param {Object} item current iteration item
- * @param {Object} params plugin params
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Kir Belevich
  */
-exports.fn = function (item, params) {
-  if (item.type === 'element') {
-    // Remove empty text element
-    if (params.text && item.name === 'text' && item.children.length === 0) {
-      return false;
-    }
-
-    // Remove empty tspan element
-    if (params.tspan && item.name === 'tspan' && item.children.length === 0) {
-      return false;
-    }
-
-    // Remove tref with empty xlink:href attribute
-    if (
-      params.tref &&
-      item.name === 'tref' &&
-      item.attributes['xlink:href'] == null
-    ) {
-      return false;
-    }
-  }
+exports.fn = (root, params) => {
+  const { text = true, tspan = true, tref = true } = params;
+  return {
+    element: {
+      enter: (node, parentNode) => {
+        // Remove empty text element
+        if (text && node.name === 'text' && node.children.length === 0) {
+          detachNodeFromParent(node, parentNode);
+        }
+        // Remove empty tspan element
+        if (tspan && node.name === 'tspan' && node.children.length === 0) {
+          detachNodeFromParent(node, parentNode);
+        }
+        // Remove tref with empty xlink:href attribute
+        if (
+          tref &&
+          node.name === 'tref' &&
+          node.attributes['xlink:href'] == null
+        ) {
+          detachNodeFromParent(node, parentNode);
+        }
+      },
+    },
+  };
 };

plugins/removeMetadata.js

@@ -1,9 +1,9 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = true;
-
 exports.description = 'removes <metadata>';
 
 /**
@@ -11,11 +11,16 @@ exports.description = 'removes <metadata>';
  *
  * https://www.w3.org/TR/SVG11/metadata.html
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Kir Belevich
  */
-exports.fn = function (item) {
-  return !item.isElem('metadata');
+exports.fn = () => {
+  return {
+    element: {
+      enter: (node, parentNode) => {
+        if (node.name === 'metadata') {
+          detachNodeFromParent(node, parentNode);
+        }
+      },
+    },
+  };
 };

plugins/removeRasterImages.js

@@ -1,9 +1,9 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = false;
-
 exports.description = 'removes raster images (disabled by default)';
 
 /**
@@ -11,18 +11,20 @@ exports.description = 'removes raster images (disabled by default)';
  *
  * @see https://bugs.webkit.org/show_bug.cgi?id=63548
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Kir Belevich
  */
-exports.fn = function (item) {
-  if (
-    item.type === 'element' &&
-    item.name === 'image' &&
-    item.attributes['xlink:href'] != null &&
-    /(\.|image\/)(jpg|png|gif)/.test(item.attributes['xlink:href'])
-  ) {
-    return false;
-  }
+exports.fn = () => {
+  return {
+    element: {
+      enter: (node, parentNode) => {
+        if (
+          node.name === 'image' &&
+          node.attributes['xlink:href'] != null &&
+          /(\.|image\/)(jpg|png|gif)/.test(node.attributes['xlink:href'])
+        ) {
+          detachNodeFromParent(node, parentNode);
+        }
+      },
+    },
+  };
 };

plugins/removeScriptElement.js

@@ -1,9 +1,9 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = false;
-
 exports.description = 'removes <script> elements (disabled by default)';
 
 /**
@@ -11,11 +11,17 @@ exports.description = 'removes <script> elements (disabled by default)';
  *
  * https://www.w3.org/TR/SVG11/script.html
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
  *
  * @author Patrick Klingemann
  */
-exports.fn = function (item) {
-  return !item.isElem('script');
+exports.fn = () => {
+  return {
+    element: {
+      enter: (node, parentNode) => {
+        if (node.name === 'script') {
+          detachNodeFromParent(node, parentNode);
+        }
+      },
+    },
+  };
 };

plugins/removeStyleElement.js

@@ -1,9 +1,9 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = false;
-
 exports.description = 'removes <style> element (disabled by default)';
 
 /**
@@ -11,11 +11,16 @@ exports.description = 'removes <style> element (disabled by default)';
  *
  * https://www.w3.org/TR/SVG11/styling.html#StyleElement
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Betsy Dupuis
  */
-exports.fn = function (item) {
-  return !item.isElem('style');
+exports.fn = () => {
+  return {
+    element: {
+      enter: (node, parentNode) => {
+        if (node.name === 'style') {
+          detachNodeFromParent(node, parentNode);
+        }
+      },
+    },
+  };
 };

plugins/removeTitle.js

@@ -1,9 +1,9 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = true;
-
 exports.description = 'removes <title>';
 
 /**
@@ -11,11 +11,16 @@ exports.description = 'removes <title>';
  *
  * https://developer.mozilla.org/en-US/docs/Web/SVG/Element/title
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Igor Kalashnikov
  */
-exports.fn = function (item) {
-  return !item.isElem('title');
+exports.fn = () => {
+  return {
+    element: {
+      enter: (node, parentNode) => {
+        if (node.name === 'title') {
+          detachNodeFromParent(node, parentNode);
+        }
+      },
+    },
+  };
 };

plugins/removeXMLProcInst.js

@@ -1,9 +1,9 @@
 'use strict';
 
-exports.type = 'perItem';
+const { detachNodeFromParent } = require('../lib/xast.js');
 
+exports.type = 'visitor';
 exports.active = true;
-
 exports.description = 'removes XML processing instructions';
 
 /**
@@ -12,14 +12,16 @@ exports.description = 'removes XML processing instructions';
  * @example
  * <?xml version="1.0" encoding="utf-8"?>
  *
- * @param {Object} item current iteration item
- * @return {Boolean} if false, item will be filtered out
- *
  * @author Kir Belevich
  */
-exports.fn = function (item) {
-  if (item.type === 'instruction' && item.name === 'xml') {
-    return false;
-  }
-  return true;
+exports.fn = () => {
+  return {
+    instruction: {
+      enter: (node, parentNode) => {
+        if (node.name === 'xml') {
+          detachNodeFromParent(node, parentNode);
+        }
+      },
+    },
+  };
 };