From 1aa92d8d9d3789aa8383f30c4d6724e80b07828a Mon Sep 17 00:00:00 2001
From: slhx agent <slhx@users.noreply.github.com>
Date: Mon, 22 Jun 2026 22:17:21 +0200
Subject: [PATCH] feat(examples): expose v0 todo field error targets

Add generated field-error targets to the v0 add and rename forms so the canonical todo example shows recoverable typed form feedback end to end instead of emitting errors with no visible target.

req: examples/001

req: canonical_authoring/003
---
 examples/v0/src/main.rs                      | 9 ++++++++-
 examples/v0/templates/partials/todo_row.heml | 1 +
 examples/v0/templates/todos.heml             | 1 +
 3 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/examples/v0/src/main.rs b/examples/v0/src/main.rs
index 5b0301b..1938f82 100644
--- a/examples/v0/src/main.rs
+++ b/examples/v0/src/main.rs
@@ -133,7 +133,7 @@ impl Hemplate for Todos {
     fn render_into(&self, buf: &mut String) -> Result<(), hemplate::error::HemplateError> {
         use std::fmt::Write as _;
 
-        buf.push_str("<section data-hemx-root=\"todos\">\n  <form data-hemx-handle=\"add_todo\" data-hemx-form=\"new_todo\">\n    <label>New todo\n      <input name=\"title\" required=\"required\">\n    </label>\n    <button type=\"submit\">Add</button>\n    <p data-hemx-form-error=\"title\"></p>\n  </form>\n\n  <p data-hemx-slot=\"summary\">");
+        buf.push_str("<section data-hemx-root=\"todos\">\n  <form data-hemx-handle=\"add_todo\" data-hemx-form=\"new_todo\">\n    <label>New todo\n      <input name=\"title\" required=\"required\">\n    </label>\n    <button type=\"submit\">Add</button>\n    <p data-hemx-error-for=\"title\"></p>\n  </form>\n\n  <p data-hemx-slot=\"summary\">");
         write!(buf, "{}", hemplate::HtmlEscape(&self.summary))?;
         buf.push_str("</p>\n  <p data-hemx-slot=\"notice\">");
         write!(buf, "{}", hemplate::HtmlEscape(&self.notice))?;
@@ -620,6 +620,13 @@ mod tests {
             .select(&selector(&escaped_markup_selector("b")))
             .next()
             .is_none());
+        assert_eq!(
+            document
+                .select(&selector("[data-hemx-error-for='title']"))
+                .count(),
+            2,
+            "add and rename forms expose generated field-error targets"
+        );
     }
 
     // req: canonical_authoring/003 req: test/005
diff --git a/examples/v0/templates/partials/todo_row.heml b/examples/v0/templates/partials/todo_row.heml
index 1d73acb..ad7ecfe 100644
--- a/examples/v0/templates/partials/todo_row.heml
+++ b/examples/v0/templates/partials/todo_row.heml
@@ -7,6 +7,7 @@
       <input name="title" +value="self.title" required="required">
     </label>
     <button type="submit">Save</button>
+    <p data-hemx-error-for="title"></p>
   </form>
   <form data-hemx-handle="delete_todo">
     <button type="submit" name="id" +value="self.id">Delete</button>
diff --git a/examples/v0/templates/todos.heml b/examples/v0/templates/todos.heml
index ed44c80..a66ea91 100644
--- a/examples/v0/templates/todos.heml
+++ b/examples/v0/templates/todos.heml
@@ -2,6 +2,7 @@
   <form data-hemx-handle="add_todo" data-hemx-form="new_todo">
     <input name="title" required="required">
     <button type="submit">Add</button>
+    <p data-hemx-error-for="title"></p>
   </form>
   <p data-hemx-slot="summary">{+ self.summary +}</p>
   <p data-hemx-slot="notice">{+ self.notice +}</p>