feat: load editor json from URL params

__tests__/editorUrl.test.ts

@@ -0,0 +1,13 @@
+import { getInitialJSONFromSearch } from "@/containers/editor/editor/url";
+
+describe("editor URL params", () => {
+  test("reads encoded json param", () => {
+    const json = '{"hello":"world","count":1}';
+
+    expect(getInitialJSONFromSearch(`?json=${encodeURIComponent(json)}`)).toBe(json);
+  });
+
+  test("returns undefined when json param is absent", () => {
+    expect(getInitialJSONFromSearch("?foo=bar")).toBeUndefined();
+  });
+});

e2e/tests/editor.spec.ts

@@ -1,5 +1,5 @@
 import { test, expect } from "@playwright/test";
-import { clearEditor, getEditor, selectAllInEditor, writeToClipboard } from "../helpers/utils";
+import { clearEditor, getEditor, getEditorText, selectAllInEditor, writeToClipboard } from "../helpers/utils";
 
 test.describe("edit in the editor", () => {
   test.beforeEach(async ({ page }) => {
@@ -37,4 +37,15 @@ test.describe("edit in the editor", () => {
     await page.keyboard.type("{");
     await expect(page.getByRole("treeitem").getByText("hello")).toBeVisible();
   });
+
+  test("loads json from URL params", async ({ page }) => {
+    const json = JSON.stringify({ hello: "world", count: 1 });
+
+    await page.goto(`/editor?json=${encodeURIComponent(json)}`);
+    await getEditor(page);
+
+    await expect(page.getByRole("treeitem").getByText("hello")).toBeVisible();
+    await expect(page.getByRole("treeitem").getByText("world")).toBeVisible();
+    await expect.poll(() => getEditorText(page)).toContain('"count": 1');
+  });
 });

src/containers/editor/editor/Editor.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { useEffect, type ComponentPropsWithoutRef } from "react";
+import { useEffect, useRef, type ComponentPropsWithoutRef } from "react";
 import Loading from "@/components/Loading";
 import { vsURL } from "@/lib/editor/cdn";
 import { EditorWrapper, type Kind } from "@/lib/editor/editor";
@@ -10,6 +10,7 @@ import { loader, Editor as MonacoEditor } from "@monaco-editor/react";
 import { useTranslations } from "next-intl";
 import { useShallow } from "zustand/shallow";
 import { example } from "./data";
+import { getInitialJSONFromSearch } from "./url";
 
 loader.config({ paths: { vs: vsURL } });
 
@@ -105,10 +106,21 @@ export function useEditTree(kind: Kind) {
 function useDisplayExample(kind: Kind) {
   const editor = useEditor("main");
   const incrEditorInitCount = useStatusStore((state) => state.incrEditorInitCount);
+  const didSetInitialText = useRef(false);
 
   useEffect(() => {
-    if (kind === "main" && editor && incrEditorInitCount() <= 1) {
-      editor.parseAndSet(example);
+    if (kind !== "main" || !editor || didSetInitialText.current) {
+      return;
     }
+
+    const initialJSON = getInitialJSONFromSearch(window.location.search);
+    const initialText = initialJSON ?? (incrEditorInitCount() <= 1 ? example : undefined);
+
+    if (initialText === undefined) {
+      return;
+    }
+
+    didSetInitialText.current = true;
+    editor.parseAndSet(initialText);
   }, [editor]);
 }

src/containers/editor/editor/url.ts

@@ -0,0 +1,6 @@
+export const initialJSONParamName = "json";
+
+export function getInitialJSONFromSearch(search: string) {
+  const searchParams = new URLSearchParams(search);
+  return searchParams.has(initialJSONParamName) ? searchParams.get(initialJSONParamName)! : undefined;
+}