From 94feac96ca7797e3a70e25c63473c3ebe5da6820 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andreas=20S=C3=B6derlund?= <ciscoheat@gmail.com>
Date: Mon, 2 Oct 2023 15:03:06 +0200
Subject: [PATCH] Added tainted to formFieldProxy.

---
 CHANGELOG.md                                  |  8 ++-
 src/lib/client/proxies.ts                     | 39 ++++++++++++++-
 src/routes/Navigation.svelte                  |  1 +
 .../tests/tainted-proxy/+page.server.ts       | 22 +++++++++
 src/routes/tests/tainted-proxy/+page.svelte   | 49 +++++++++++++++++++
 src/routes/tests/tainted-proxy/schema.ts      |  7 +++
 6 files changed, 123 insertions(+), 3 deletions(-)
 create mode 100644 src/routes/tests/tainted-proxy/+page.server.ts
 create mode 100644 src/routes/tests/tainted-proxy/+page.svelte
 create mode 100644 src/routes/tests/tainted-proxy/schema.ts

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 98fe6652..2dcc9454 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,11 +5,15 @@ Headlines: Added, Changed, Deprecated, Removed, Fixed, Security
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [Unreleased]
+## [1.8.0]
 
 ### Fixed
 
-- [Array errors](https://superforms.rocks/concepts/error-handling#form-level-and-array-errors) were always added, even if the form wasn't tainted.
+- [Array errors](https://superforms.rocks/concepts/error-handling#form-level-and-array-errors) were always added, even if the array or any data in it hadn't tainted the form.
+
+### Added
+
+- [formFieldProxy](https://superforms.rocks/components#using-a-formfieldproxy) now contains a proxy for `tainted`.
 
 ## [1.7.4] - 2023-09-29
 
diff --git a/src/lib/client/proxies.ts b/src/lib/client/proxies.ts
index 32bed857..b5773750 100644
--- a/src/lib/client/proxies.ts
+++ b/src/lib/client/proxies.ts
@@ -245,6 +245,7 @@ export function formFieldProxy<
   value: Writable<FormPathType<z.infer<UnwrapEffects<T>>, Path>>;
   errors: Writable<string[] | undefined>;
   constraints: Writable<InputConstraint | undefined>;
+  tainted: Writable<boolean | undefined>;
 } {
   const path2 = splitPath<z.infer<UnwrapEffects<T>>>(path);
   // Filter out array indices, the constraints structure doesn't contain these.
@@ -252,6 +253,41 @@ export function formFieldProxy<
     .filter((p) => isNaN(parseInt(String(p))))
     .join('.');
 
+  const taintedProxy = derived<typeof form.tainted, boolean | undefined>(
+    form.tainted,
+    ($tainted) => {
+      if (!$tainted) return $tainted;
+      const taintedPath = traversePath($tainted, path2);
+      return taintedPath ? taintedPath.value : undefined;
+    }
+  );
+
+  const tainted = {
+    subscribe: taintedProxy.subscribe,
+    update(upd: Updater<boolean | undefined>) {
+      form.tainted.update(($tainted) => {
+        if (!$tainted) $tainted = {};
+        const output = traversePath($tainted, path2, (path) => {
+          if (!path.value) path.parent[path.key] = {};
+          return path.parent[path.key];
+        });
+        if (output) output.parent[output.key] = upd(output.value);
+        return $tainted;
+      });
+    },
+    set(value: boolean | undefined) {
+      form.tainted.update(($tainted) => {
+        if (!$tainted) $tainted = {};
+        const output = traversePath($tainted, path2, (path) => {
+          if (!path.value) path.parent[path.key] = {};
+          return path.parent[path.key];
+        });
+        if (output) output.parent[output.key] = value;
+        return $tainted;
+      });
+    }
+  };
+
   return {
     path,
     value: fieldProxy(form.form, path),
@@ -261,7 +297,8 @@ export function formFieldProxy<
     constraints: fieldProxy(
       form.constraints,
       constraintsPath as never
-    ) as Writable<InputConstraint | undefined>
+    ) as Writable<InputConstraint | undefined>,
+    tainted
   };
 }
 
diff --git a/src/routes/Navigation.svelte b/src/routes/Navigation.svelte
index 2b487842..68448ed0 100644
--- a/src/routes/Navigation.svelte
+++ b/src/routes/Navigation.svelte
@@ -27,6 +27,7 @@
   <a href="/tests/flash-onerror">Flash onError</a>
   <a href="/tests/reset-component">Reset component 1</a>
   <a href="/tests/reset-component-2">Reset component 2</a>
+  <a href="/tests/tainted-proxy">Tainted formFieldProxy</a>
 </nav>
 
 <style lang="scss">
diff --git a/src/routes/tests/tainted-proxy/+page.server.ts b/src/routes/tests/tainted-proxy/+page.server.ts
new file mode 100644
index 00000000..0d9c7ac3
--- /dev/null
+++ b/src/routes/tests/tainted-proxy/+page.server.ts
@@ -0,0 +1,22 @@
+import { message, superValidate } from '$lib/server';
+import { schema } from './schema';
+import { fail } from '@sveltejs/kit';
+
+export const load = async () => {
+  const form = await superValidate(schema);
+  return { form };
+};
+
+export const actions = {
+  default: async ({ request }) => {
+    const formData = await request.formData();
+    console.log(formData);
+
+    const form = await superValidate(formData, schema);
+    console.log('POST', form);
+
+    if (!form.valid) return fail(400, { form });
+
+    return message(form, 'Posted OK!');
+  }
+};
diff --git a/src/routes/tests/tainted-proxy/+page.svelte b/src/routes/tests/tainted-proxy/+page.svelte
new file mode 100644
index 00000000..f3e54452
--- /dev/null
+++ b/src/routes/tests/tainted-proxy/+page.svelte
@@ -0,0 +1,49 @@
+<script lang="ts">
+  import { formFieldProxy, superForm } from '$lib/client';
+  import type { PageData } from './$types';
+  import SuperDebug from '$lib/client/SuperDebug.svelte';
+
+  export let data: PageData;
+
+  const form = superForm(data.form, {
+    dataType: 'json'
+  });
+
+  const { message, tainted: formTainted, enhance } = form;
+  const { value, errors, tainted } = formFieldProxy(form, 'user.name');
+</script>
+
+<SuperDebug data={$formTainted} />
+
+{#if $message}<h4>{$message}</h4>{/if}
+
+<p>Proxy: {$tainted} - Form: {$formTainted?.user?.name}</p>
+
+<p>
+  <br />
+  <button on:click={() => ($tainted = false)}>Untaint user.name</button>
+</p>
+
+<form method="POST" use:enhance>
+  <label>
+    Name: <input name="name" bind:value={$value} />
+    {#if $errors}<span class="invalid">{$errors}</span>{/if}
+  </label>
+  <div>
+    <button>Submit</button>
+  </div>
+</form>
+
+<style lang="scss">
+  form {
+    margin: 2rem 0;
+
+    input {
+      background-color: #dedede;
+    }
+
+    .invalid {
+      color: crimson;
+    }
+  }
+</style>
diff --git a/src/routes/tests/tainted-proxy/schema.ts b/src/routes/tests/tainted-proxy/schema.ts
new file mode 100644
index 00000000..9b731188
--- /dev/null
+++ b/src/routes/tests/tainted-proxy/schema.ts
@@ -0,0 +1,7 @@
+import { z } from 'zod';
+
+export const schema = z.object({
+  user: z.object({
+    name: z.string().min(1)
+  })
+});