Deepen JSON formatter: tree view, copy path, per-field expansion, auto-fixes, lossless numbers

CHANGELOG.md

@@ -7,7 +7,28 @@ this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
-Nothing yet.
+### Added
+- JSON Formatter: a Tree view alongside the text output. It shows the same
+  document the text does, with sorted keys and expanded embedded JSON, as a
+  collapsible tree. Only the rows on screen are rendered, so large documents
+  scroll smoothly. It opens a couple of levels deep, and has Expand all /
+  Collapse all and full keyboard navigation (arrow keys, Home/End, Enter).
+- JSON Formatter: copy the selected tree node's path as an RFC 6901 pointer
+  (`/items/0/id`), a dot path (`items[0].id`) or a jq path (`.items[0].id`).
+- JSON Formatter: embedded JSON strings can be expanded one field at a time.
+  A field nested inside another payload unlocks once its parent is expanded.
+- JSON Formatter: auto-fixes for almost-JSON. It strips a JSONP wrapper, the
+  `)]}'` prefix, a byte-order mark and comments; converts single quotes;
+  quotes bare keys; and removes trailing commas. Apply them in place, or
+  review the change side by side in Diff first.
+- JSON Formatter: lossless mode. When a document has numbers JavaScript
+  cannot hold exactly, like `12345678901234567890`, format and minify keep
+  them digit for digit instead of rounding them. This includes numbers inside
+  expanded embedded JSON.
+
+### Fixed
+- JSON Formatter: with "Expand embedded JSON" on, a key named `__proto__`
+  was silently dropped from the output. It is now kept like any other key.
 
 ## [0.3.0] — 2026-09-25
 

package.json

@@ -21,6 +21,7 @@
     "@codemirror/merge": "6.12.2",
     "@codemirror/state": "6.7.5",
     "@codemirror/view": "6.43.12",
+    "@tanstack/react-virtual": "3.14.12",
     "change-case": "5.4.4",
     "clsx": "2.1.1",
     "cmdk": "1.1.1",

src/lib/persist/handoff.ts

@@ -0,0 +1,30 @@
+import { TOOLS_BY_SLUG, type ToolSlug } from '@/lib/registry'
+import { readIdb, writeIdb } from './idb'
+import { readLocal, writeLocal } from './store'
+
+/**
+ * Seed another tool's saved state before navigating to it -- e.g. the JSON
+ * tool opening its auto-fix preview in Diff.
+ *
+ * The patch is merged over whatever the target has stored, and `useToolState`
+ * merges that over the tool's own defaults on mount, so the caller only names
+ * the fields it means to set and never needs the target's module (importing it
+ * would pull that tool's chunk into the caller's).
+ *
+ * Resolves false for a `store: 'none'` tool (there is nowhere to put it) or a
+ * failed write, so the caller can stay put instead of opening an empty tool.
+ */
+export async function handOff<T extends object>(slug: ToolSlug, patch: Partial<T>): Promise<boolean> {
+  const tool = TOOLS_BY_SLUG[slug]
+  const version = tool.stateVersion
+
+  if (tool.store.kind === 'idb') {
+    const current = (await readIdb<T>(slug, version)) ?? {}
+    return writeIdb(slug, version, { ...current, ...patch })
+  }
+  if (tool.store.kind === 'local') {
+    const current = readLocal<T>(slug, version) ?? {}
+    return writeLocal(slug, version, { ...current, ...patch }) === 'ok'
+  }
+  return false
+}