refactor(mergePaths): improve performance on large files (svg#1764)

package.json

@@ -103,6 +103,6 @@
     "rollup": "^2.79.1",
     "rollup-plugin-terser": "^7.0.2",
     "tar-stream": "^3.1.6",
-    "typescript": "^4.8.4"
+    "typescript": "^5.3.3"
   }
 }

plugins/convertPathData.js

@@ -154,7 +154,8 @@ exports.fn = (root, params) => {
             precision !== false
               ? +Math.pow(0.1, precision).toFixed(precision)
               : 1e-2;
-          roundData = precision > 0 && precision < 20 ? strongRound : round;
+          roundData =
+            precision && precision > 0 && precision < 20 ? strongRound : round;
           if (makeArcs) {
             arcThreshold = makeArcs.threshold;
             arcTolerance = makeArcs.tolerance;

plugins/mergePaths.js

@@ -1,7 +1,9 @@
 'use strict';
 
 /**
+ * @typedef {import("../lib/types").PathDataItem} PathDataItem
  * @typedef {import('../lib/types').XastChild} XastChild
+ * @typedef {import('../lib/types').XastElement} XastElement
  */
 
 const { collectStylesheet, computeStyle } = require('../lib/style.js');
@@ -35,6 +37,19 @@ exports.fn = (root, params) => {
         /** @type {XastChild[]} */
         const elementsToRemove = [];
         let prevChild = node.children[0];
+        let prevPathData = null;
+
+        /**
+         * @param {XastElement} child
+         * @param {PathDataItem[]} pathData
+         */
+        const updatePreviousPath = (child, pathData) => {
+          js2path(child, pathData, {
+            floatPrecision,
+            noSpaceAfterFlags,
+          });
+          prevPathData = null;
+        };
 
         for (let i = 1; i < node.children.length; i++) {
           const child = node.children[i];
@@ -45,6 +60,9 @@ exports.fn = (root, params) => {
             prevChild.children.length !== 0 ||
             prevChild.attributes.d == null
           ) {
+            if (prevPathData && prevChild.type === 'element') {
+              updatePreviousPath(prevChild, prevPathData);
+            }
             prevChild = child;
             continue;
           }
@@ -55,6 +73,9 @@ exports.fn = (root, params) => {
             child.children.length !== 0 ||
             child.attributes.d == null
           ) {
+            if (prevPathData) {
+              updatePreviousPath(prevChild, prevPathData);
+            }
             prevChild = child;
             continue;
           }
@@ -65,12 +86,17 @@ exports.fn = (root, params) => {
             computedStyle['marker-mid'] ||
             computedStyle['marker-end']
           ) {
+            if (prevPathData) {
+              updatePreviousPath(prevChild, prevPathData);
+            }
             prevChild = child;
             continue;
           }
-
           const childAttrs = Object.keys(child.attributes);
           if (childAttrs.length !== Object.keys(prevChild.attributes).length) {
+            if (prevPathData) {
+              updatePreviousPath(prevChild, prevPathData);
+            }
             prevChild = child;
             continue;
           }
@@ -84,25 +110,33 @@ exports.fn = (root, params) => {
           });
 
           if (areAttrsEqual) {
+            if (prevPathData) {
+              updatePreviousPath(prevChild, prevPathData);
+            }
             prevChild = child;
             continue;
           }
 
-          const prevPathJS = path2js(prevChild);
-          const curPathJS = path2js(child);
-
-          if (force || !intersects(prevPathJS, curPathJS)) {
-            prevPathJS.push(...curPathJS);
-            js2path(prevChild, prevPathJS, {
-              floatPrecision,
-              noSpaceAfterFlags,
-            });
+          const hasPrevPath = prevPathData != null;
+          const currentPathData = path2js(child);
+          prevPathData = prevPathData ?? path2js(prevChild);
 
+          if (force || !intersects(prevPathData, currentPathData)) {
+            prevPathData.push(...currentPathData);
             elementsToRemove.push(child);
             continue;
           }
 
+          if (hasPrevPath) {
+            updatePreviousPath(prevChild, prevPathData);
+          }
+
           prevChild = child;
+          prevPathData = null;
+        }
+
+        if (prevPathData && prevChild.type === 'element') {
+          updatePreviousPath(prevChild, prevPathData);
         }
 
         node.children = node.children.filter(

yarn.lock

@@ -4449,7 +4449,7 @@ __metadata:
     rollup: ^2.79.1
     rollup-plugin-terser: ^7.0.2
     tar-stream: ^3.1.6
-    typescript: ^4.8.4
+    typescript: ^5.3.3
   bin:
     svgo: ./bin/svgo
   languageName: unknown
@@ -4572,23 +4572,23 @@ __metadata:
   languageName: node
   linkType: hard
 
-"typescript@npm:^4.8.4":
-  version: 4.8.4
-  resolution: "typescript@npm:4.8.4"
+"typescript@npm:^5.3.3":
+  version: 5.3.3
+  resolution: "typescript@npm:5.3.3"
   bin:
     tsc: bin/tsc
     tsserver: bin/tsserver
-  checksum: 3e4f061658e0c8f36c820802fa809e0fd812b85687a9a2f5430bc3d0368e37d1c9605c3ce9b39df9a05af2ece67b1d844f9f6ea8ff42819f13bcb80f85629af0
+  checksum: 2007ccb6e51bbbf6fde0a78099efe04dc1c3dfbdff04ca3b6a8bc717991862b39fd6126c0c3ebf2d2d98ac5e960bcaa873826bb2bb241f14277034148f41f6a2
   languageName: node
   linkType: hard
 
-"typescript@patch:typescript@^4.8.4#~builtin<compat/typescript>":
-  version: 4.8.4
-  resolution: "typescript@patch:typescript@npm%3A4.8.4#~builtin<compat/typescript>::version=4.8.4&hash=a1c5e5"
+"typescript@patch:typescript@^5.3.3#~builtin<compat/typescript>":
+  version: 5.3.3
+  resolution: "typescript@patch:typescript@npm%3A5.3.3#~builtin<compat/typescript>::version=5.3.3&hash=a1c5e5"
   bin:
     tsc: bin/tsc
     tsserver: bin/tsserver
-  checksum: 563a0ef47abae6df27a9a3ab38f75fc681f633ccf1a3502b1108e252e187787893de689220f4544aaf95a371a4eb3141e4a337deb9895de5ac3c1ca76430e5f0
+  checksum: f61375590b3162599f0f0d5b8737877ac0a7bc52761dbb585d67e7b8753a3a4c42d9a554c4cc929f591ffcf3a2b0602f65ae3ce74714fd5652623a816862b610
   languageName: node
   linkType: hard