cleanupAttributes: handle identity transforms (#182)

Author: johnkenny54

lib/css/styleData.js

@@ -136,33 +136,12 @@ export class StyleData {
 
     // Override with style element rules.
     const importantProperties = new Set();
-    for (const rule of this.getSortedRules()) {
-      if (rule.matches(element)) {
-        const isDynamic = rule.isInMediaQuery() || rule.hasPseudos();
-        for (const [name, value] of rule.getDeclarationEntries()) {
-          if (isDynamic) {
-            computedStyles.set(name, null);
-          } else {
-            const hasVars = value.toString().includes('var(');
-            if (hasVars) {
-              computedStyles.set(name, null);
-            } else if (geometryProperties[name]) {
-              // Support for geometry properties is inconsistent. Avoid changing these.
-              computedStyles.set(name, null);
-            } else {
-              computedStyles.set(name, value);
-              if (value.isImportant()) {
-                importantProperties.add(name);
-              }
-            }
-          }
-        }
-      }
-    }
+    this.computeStyleElementProps(element, computedStyles, importantProperties);
 
     // Override with inline styles.
     if (!declarations) {
-      const styleAttValue = StyleAttValue.getAttValue(element);
+      /** @type {StyleAttValue|undefined} */
+      const styleAttValue = element.svgAtts.get('style');
       if (styleAttValue) {
         declarations = new SvgAttMap(styleAttValue.entries());
       }
@@ -347,6 +326,45 @@ export class StyleData {
     return computedStyles;
   }
 
+  /**
+   * @param {import('../types.js').XastElement} element
+   * @param {import('../types.js').ComputedPropertyMap} [computedStyles]
+   * @param {Set<string>} [importantProperties]
+   * @returns {import('../types.js').ComputedPropertyMap}
+   */
+  computeStyleElementProps(
+    element,
+    computedStyles = new Map(),
+    importantProperties = new Set(),
+  ) {
+    // Override with style element rules.
+    for (const rule of this.getSortedRules()) {
+      if (rule.matches(element)) {
+        const isDynamic = rule.isInMediaQuery() || rule.hasPseudos();
+        for (const [name, value] of rule.getDeclarationEntries()) {
+          if (isDynamic) {
+            computedStyles.set(name, null);
+          } else {
+            const hasVars = value.toString().includes('var(');
+            if (hasVars) {
+              computedStyles.set(name, null);
+            } else if (geometryProperties[name]) {
+              // Support for geometry properties is inconsistent. Avoid changing these.
+              computedStyles.set(name, null);
+            } else {
+              computedStyles.set(name, value);
+              if (value.isImportant()) {
+                importantProperties.add(name);
+              }
+            }
+          }
+        }
+      }
+    }
+
+    return computedStyles;
+  }
+
   /** @param {Set<import('./css.js').CSSRule>}  rules */
   deleteRules(rules) {
     if (rules.size === 0) {

lib/tools-ast.js

@@ -65,6 +65,22 @@ export function addReferencedIdsInStyleAttribute2(refs, element, properties) {
   }
 }
 
+/**
+ * @param {import('./types.js').XastElement} element
+ * @param {string} propName
+ */
+export function deleteAttAndProp(element, propName) {
+  element.svgAtts.delete(propName);
+  /** @type {import('../types/types.js').StyleAttValue|undefined} */
+  const styleAtt = element.svgAtts.get('style');
+  if (styleAtt !== undefined) {
+    styleAtt.delete(propName);
+    if (styleAtt.count() === 0) {
+      element.svgAtts.delete('style');
+    }
+  }
+}
+
 /**
  * @param {import('./types.js').XastElement} element
  * @param {...string} attNames

lib/types.d.ts

@@ -142,7 +142,10 @@ export type ComputedPropertyMap = Map<string, AttValue | null>;
 
 export class StyleData {
   addStyleSection(css: string): void;
-  computeOwnProps(node: XastElement): ComputedPropertyMap;
+  computeOwnProps(
+    element: XastElement,
+    declarations?: SvgAttValues,
+  ): ComputedPropertyMap;
   /** @deprecated */
   computeOwnStyle(node: XastElement): Map<string, string | null>;
   computeParentProps(parentList: Readonly<ParentList>): ComputedPropertyMap;
@@ -161,6 +164,7 @@ export class StyleData {
     parentList: Readonly<ParentList>,
     declarations?: SvgAttValues,
   ): ComputedStyleMap;
+  computeStyleElementProps(element: XastElement): ComputedPropertyMap;
   deleteRules(rules: Set<CSSRule>): void;
   getFeatures(): Set<CSSFeatures>;
   getIdsReferencedByProperties(): string[];

lib/types/svgTransforms.js

@@ -148,6 +148,10 @@ export function svgStringifyTransform(transforms) {
         break;
     }
   }
+
+  if (transforms.length === 0) {
+    return 'scale(1)';
+  }
   let str = '';
   for (let index = 0; index < transforms.length; index++) {
     const fn = transforms[index];
@@ -202,6 +206,10 @@ export function svgStringifyTransformAsProperty(transforms) {
         throw new Error();
     }
   }
+
+  if (transforms.length === 0) {
+    return 'scale(1)';
+  }
   return transforms.reduce(
     (str, transform) => (str += stringify(transform)),
     '',