Rewrite layout algorithm internals [draft]

.github/workflows/e2e-ci.yml

@@ -10,10 +10,10 @@ jobs:
         with:
           version: 7
       - name: Install dependencies
-        run: pnpm install -r
+        run: pnpm install --frozen-lockfile --recursive
       - name: Install Playwright dependencies
         run: npx playwright install
       - name: Build NPM package
         run: pnpm prerelease
       - name: Run Playwright tests
-        run: cd packages/react-resizable-panels-website && pnpm test:e2e
+        run: cd packages/react-resizable-panels-website && pnpm test:e2e

.github/workflows/eslint.yml

@@ -10,6 +10,6 @@ jobs:
         with:
           version: 7
       - name: Install dependencies
-        run: pnpm install -r
+        run: pnpm install --frozen-lockfile --recursive
       - name: Run ESLint
         run: pnpm lint

.github/workflows/jest.yml

@@ -0,0 +1,17 @@
+name: "Jest"
+on: [pull_request]
+jobs:
+  tests-e2e:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-node@v3
+      - uses: pnpm/action-setup@v2
+        with:
+          version: 7
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile --recursive
+      - name: Build NPM packages
+        run: pnpm run prerelease
+      - name: Run tests
+        run: cd packages/react-resizable-panels && pnpm run test

.github/workflows/prettier.yml

@@ -10,6 +10,6 @@ jobs:
         with:
           version: 7
       - name: Install dependencies
-        run: pnpm install -r
+        run: pnpm install --frozen-lockfile --recursive
       - name: Run Prettier
         run: pnpm run prettier:ci

.github/workflows/typescript.yml

@@ -10,7 +10,7 @@ jobs:
         with:
           version: 7
       - name: Install dependencies
-        run: pnpm install -r
+        run: pnpm install --frozen-lockfile --recursive
       - name: Build NPM package
         run: pnpm prerelease
       - name: Run TypeScript

.npmrc

@@ -0,0 +1 @@
+auto-install-peers=false

README.md

@@ -1,12 +1,13 @@
 <img width="328" alt="React Resizable Panels logo" src="https://user-images.githubusercontent.com/29597/210075327-faeb4ca8-31df-4dc8-a649-01d0ee3cd315.png" />
 
 ## react-resizable-panels
+
 React components for resizable panel groups/layouts.
 
-* [View the website](https://react-resizable-panels.vercel.app/)
-* [Try it on CodeSandbox](https://codesandbox.io/s/react-resizable-panels-zf7hwd)
-* [Read the documentation](https://github.com/bvaughn/react-resizable-panels/tree/main/packages/react-resizable-panels)
-* [View the changelog](https://github.com/bvaughn/react-resizable-panels/blob/main/packages/react-resizable-panels/CHANGELOG.md)
+- [View the website](https://react-resizable-panels.vercel.app/)
+- [Try it on CodeSandbox](https://codesandbox.io/s/react-resizable-panels-zf7hwd)
+- [Read the documentation](https://github.com/bvaughn/react-resizable-panels/tree/main/packages/react-resizable-panels)
+- [View the changelog](https://github.com/bvaughn/react-resizable-panels/blob/main/packages/react-resizable-panels/CHANGELOG.md)
 
 Supported input methods include mouse, touch, and keyboard (via [Window Splitter](https://www.w3.org/WAI/ARIA/apg/patterns/windowsplitter/)).
 
@@ -26,13 +27,13 @@ The `Panel` API doesn't _require_ `id` and `order` props because they aren't nec
 <PanelGroup direction="horizontal">
   {renderSideBar && (
     <>
-      <Panel id="sidebar" minSize={25} order={1}>
+      <Panel id="sidebar" minSizePercentage={25} order={1}>
         <Sidebar />
       </Panel>
       <PanelResizeHandle />
     </>
   )}
-  <Panel minSize={25} order={2}>
+  <Panel minSizePercentage={25} order={2}>
     <Main />
   </Panel>
 </PanelGroup>
@@ -43,6 +44,7 @@ The `Panel` API doesn't _require_ `id` and `order` props because they aren't nec
 By default, this library uses `localStorage` to persist layouts. With server rendering, this can cause a flicker when the default layout (rendered on the server) is replaced with the persisted layout (in `localStorage`). The way to avoid this flicker is to also persist the layout with a cookie like so:
 
 ##### Server component
+
 ```tsx
 import ResizablePanels from "@/app/ResizablePanels";
 import { cookies } from "next/headers";
@@ -60,32 +62,29 @@ export function ServerComponent() {
 ```
 
 ##### Client component
+
 ```tsx
 "use client";
 
 import { Panel, PanelGroup, PanelResizeHandle } from "react-resizable-panels";
 
 export function ClientComponent({
-  defaultLayout = [33, 67]
+  defaultLayout = [33, 67],
 }: {
-  defaultLayout: number[] | undefined
+  defaultLayout: number[] | undefined;
 }) {
   const onLayout = (sizes: number[]) => {
     document.cookie = `react-resizable-panels:layout=${JSON.stringify(sizes)}`;
   };
 
   return (
     <PanelGroup direction="horizontal" onLayout={onLayout}>
-      <Panel defaultSize={defaultLayout[0]}>
-        {/* ... */}
-      </Panel>
+      <Panel defaultSizePercentage={defaultLayout[0]}>{/* ... */}</Panel>
       <PanelResizeHandle className="w-2 bg-blue-800" />
-      <Panel defaultSize={defaultLayout[1]}>
-        {/* ... */}
-      </Panel>
+      <Panel defaultSizePercentage={defaultLayout[1]}>{/* ... */}</Panel>
     </PanelGroup>
   );
 }
 ```
 
-A demo of this is available [here](https://github.com/bvaughn/react-resizable-panels-demo-ssr).
+A demo of this is available [here](https://github.com/bvaughn/react-resizable-panels-demo-ssr).

package.json

@@ -21,19 +21,23 @@
     "typescript:watch": "tsc --noEmit --watch"
   },
   "devDependencies": {
-    "@babel/preset-typescript": "^7.21.5",
-    "@playwright/test": "^1.35.0",
-    "@types/node": "^18.15.11",
-    "@types/react": "^18.0.26",
-    "@types/react-dom": "^18.0.10",
-    "@typescript-eslint/eslint-plugin": "^5.57.0",
-    "@typescript-eslint/parser": "^5.57.0",
-    "@typescript-eslint/type-utils": "^5.57.0",
-    "eslint": "^8.37.0",
+    "@babel/preset-typescript": "^7.22.5",
+    "@playwright/test": "^1.37.0",
+    "@types/jest": "^29.5.3",
+    "@types/node": "^18.17.5",
+    "@types/react": "^18.2.20",
+    "@types/react-dom": "^18.2.7",
+    "@typescript-eslint/eslint-plugin": "^5.62.0",
+    "@typescript-eslint/parser": "^5.62.0",
+    "@typescript-eslint/type-utils": "^5.62.0",
+    "eslint": "^8.47.0",
+    "jest": "^29.6.2",
+    "jest-environment-jsdom": "^29.6.2",
     "parcel": "^2.9.3",
     "prettier": "latest",
     "process": "^0.11.10",
-    "typescript": ">=3.0.0"
+    "ts-jest": "^29.1.1",
+    "typescript": "^5.1.6"
   },
   "dependencies": {
     "@parcel/config-default": "^2.9.3",

packages/react-resizable-panels-website/src/components/ResizeHandle.tsx

@@ -3,7 +3,7 @@ import { PanelResizeHandle } from "react-resizable-panels";
 import Icon from "./Icon";
 import styles from "./ResizeHandle.module.css";
 
-export default function ResizeHandle({
+export function ResizeHandle({
   className = "",
   collapsed = false,
   id,

packages/react-resizable-panels-website/src/routes/EndToEndTesting/index.tsx

@@ -9,8 +9,7 @@ import {
 import {
   ImperativePanelGroupHandle,
   ImperativePanelHandle,
-  Units,
-  getAvailableGroupSizePixels,
+  MixedSizes,
 } from "react-resizable-panels";
 
 import { urlPanelGroupToPanelGroup, urlToUrlData } from "../../utils/UrlData";
@@ -55,8 +54,10 @@ function EndToEndTesting() {
   const [panelIds, setPanelIds] = useState<string[]>([]);
   const [panelGroupId, setPanelGroupId] = useState("");
   const [panelGroupIds, setPanelGroupIds] = useState<string[]>([]);
-  const [size, setSize] = useState(0);
-  const [units, setUnits] = useState("");
+  const [sizePercentage, setSizePercentage] = useState<number | undefined>(
+    undefined
+  );
+  const [sizePixels, setSizePixels] = useState<number | undefined>(undefined);
   const [layoutString, setLayoutString] = useState("");
 
   const debugLogRef = useRef<ImperativeDebugLogHandle>(null);
@@ -80,10 +81,6 @@ function EndToEndTesting() {
       );
       setPanelGroupIds(panelGroupIds);
       setPanelGroupId(panelGroupIds[0]);
-
-      // const panelGroupElement = document.querySelector("[data-panel-group]")!;
-      // const units = panelGroupElement.getAttribute("data-panel-group-units")!;
-      // setUnits(units);
     };
 
     window.addEventListener("popstate", (event) => {
@@ -113,12 +110,11 @@ function EndToEndTesting() {
             panelId
           ) as ImperativePanelHandle;
           if (panel != null) {
-            const percentage = panel.getSize("percentages");
-            const pixels = panel.getSize("pixels");
+            const { sizePercentage, sizePixels } = panel.getSize();
 
-            panelElement.textContent = `${percentage.toFixed(
+            panelElement.textContent = `${sizePercentage.toFixed(
               1
-            )}%\n${pixels.toFixed(1)}px`;
+            )}%\n${sizePixels.toFixed(1)}px`;
           }
         }
       }, 0);
@@ -174,12 +170,16 @@ function EndToEndTesting() {
 
   const onSizeInputChange = (event: ChangeEvent<HTMLInputElement>) => {
     const value = event.currentTarget.value;
-    setSize(parseFloat(value));
-  };
 
-  const onUnitsSelectChange = (event: ChangeEvent<HTMLSelectElement>) => {
-    const value = event.currentTarget.value;
-    setUnits(value);
+    if (value.endsWith("%")) {
+      setSizePercentage(parseFloat(value));
+      setSizePixels(undefined);
+    } else if (value.endsWith("px")) {
+      setSizePercentage(undefined);
+      setSizePixels(parseFloat(value));
+    } else {
+      throw Error(`Invalid size: ${value}`);
+    }
   };
 
   const onCollapseButtonClick = () => {
@@ -202,18 +202,28 @@ function EndToEndTesting() {
     const idToRefMap = idToRefMapRef.current;
     const panel = idToRefMap.get(panelId);
     if (panel && assertImperativePanelHandle(panel)) {
-      panel.resize(size, (units as any) || undefined);
+      panel.resize({ sizePercentage, sizePixels });
     }
   };
 
   const onSetLayoutButton = () => {
     const idToRefMap = idToRefMapRef.current;
     const panelGroup = idToRefMap.get(panelGroupId);
     if (panelGroup && assertImperativePanelGroupHandle(panelGroup)) {
-      panelGroup.setLayout(
-        JSON.parse(layoutString),
-        (units as any) || undefined
+      const trimmedLayoutString = layoutString.substring(
+        1,
+        layoutString.length - 1
       );
+      const layout = trimmedLayoutString.split(",").map((text) => {
+        if (text.endsWith("%")) {
+          return { sizePercentage: parseFloat(text) };
+        } else if (text.endsWith("px")) {
+          return { sizePixels: parseFloat(text) };
+        } else {
+          throw Error(`Invalid layout: ${layoutString}`);
+        }
+      }) satisfies Partial<MixedSizes>[];
+      panelGroup.setLayout(layout);
     }
   };
 
@@ -251,8 +261,8 @@ function EndToEndTesting() {
             className={styles.Input}
             id="sizeInput"
             onChange={onSizeInputChange}
-            placeholder="Size"
-            type="number"
+            placeholder="Size (% or px)"
+            type="text"
           />
           <button
             id="resizeButton"
@@ -262,18 +272,6 @@ function EndToEndTesting() {
             <Icon type="resize" />
           </button>
           <div className={styles.Spacer} />
-          <select
-            className={styles.Input}
-            defaultValue={units}
-            id="unitsSelect"
-            onChange={onUnitsSelectChange}
-            placeholder="Units"
-          >
-            <option value=""></option>
-            <option value="percentages">percentages</option>
-            <option value="pixels">pixels</option>
-          </select>
-          <div className={styles.Spacer} />
           <select
             className={styles.Input}
             id="panelGroupIdSelect"
@@ -302,8 +300,8 @@ function EndToEndTesting() {
           </button>
         </div>
       </div>
-      <div className={styles.Children}>{children}</div>
       <DebugLog apiRef={debugLogRef} />
+      <div className={styles.Children}>{children}</div>
     </div>
   );
 }

packages/react-resizable-panels-website/src/routes/examples/Collapsible.tsx

@@ -1,4 +1,5 @@
 import { useReducer } from "react";
+
 import { Panel, PanelGroup, PanelResizeHandle } from "react-resizable-panels";
 
 import {
@@ -56,25 +57,30 @@ function Content() {
     dispatch({ type: "open", file });
   };
 
-  const toggleCollapsed = (collapsed: boolean) => {
-    dispatch({ type: "toggleCollapsed", collapsed });
+  const onCollapse = () => {
+    dispatch({ type: "toggleCollapsed", collapsed: false });
+  };
+
+  const onExpand = () => {
+    dispatch({ type: "toggleCollapsed", collapsed: true });
   };
 
   return (
     <div className={sharedStyles.PanelGroupWrapper}>
-      <PanelGroup className={styles.IDE} direction="horizontal" units="pixels">
+      <PanelGroup className={styles.IDE} direction="horizontal">
         <div className={styles.Toolbar}>
           <Icon className={styles.ToolbarIconActive} type="files" />
           <Icon className={styles.ToolbarIcon} type="search" />
         </div>
         <Panel
           className={sharedStyles.PanelColumn}
-          collapsedSize={36}
+          collapsedSizePixels={36}
           collapsible={true}
-          defaultSize={150}
-          maxSize={150}
-          minSize={60}
-          onCollapse={toggleCollapsed}
+          defaultSizePixels={150}
+          maxSizePixels={150}
+          minSizePixels={60}
+          onCollapse={onCollapse}
+          onExpand={onExpand}
         >
           <div className={styles.FileList}>
             <div className={styles.DirectoryEntry}>
@@ -103,7 +109,7 @@ function Content() {
               : styles.ResizeHandle
           }
         />
-        <Panel className={sharedStyles.PanelColumn} minSize={10}>
+        <Panel className={sharedStyles.PanelColumn} minSizePercentage={50}>
           <div className={styles.SourceTabs}>
             {Array.from(openFiles).map((file) => (
               <div
@@ -169,7 +175,7 @@ const FILES: File[] = FILE_PATHS.map(([path, code]) => {
 const CODE = `
 <PanelGroup direction="horizontal">
   <SideTabBar />
-  <Panel collapsedSize={5} collapsible={true} minSize={10}>
+  <Panel collapsible={true} collapsedSizePixels={35} minSizePercentage={10}>
     <SourceBrowser />
   </Panel>
   <PanelResizeHandle />