From 6e65487767f6ef5360d3eaf2e10374f5dcb1de8b Mon Sep 17 00:00:00 2001
From: Navid EMAD <navid.emad@yespark.fr>
Date: Mon, 27 Apr 2026 22:25:55 +0200
Subject: [PATCH] forms: extract Select.effectiveOption to centralize
 selectedness

Per review: collectForm walked the children once to look for a
non-disabled <option>, then Select.getValue walked them again to
emit the value. Extract the selectedness-candidate algorithm into
Select.effectiveOption() ?*Option so both call sites share it and
each runs a single iteration.

- Select.getValue is now a one-liner over effectiveOption.
- collectForm replaces the candidate-check + getValue pair with
  `select.effectiveOption() orelse continue; break :blk opt.getValue(frame);`.

Behavior is unchanged; the existing form_data.html fixtures
(selectWithoutOptions, selectMultipleWithoutOptions,
selectAllOptionsDisabled) still pass.
---
 src/browser/webapi/element/html/Select.zig | 18 +++++++++++++-----
 src/browser/webapi/net/FormData.zig        | 18 ++++++------------
 2 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/src/browser/webapi/element/html/Select.zig b/src/browser/webapi/element/html/Select.zig
index 5ad09e39..a840c533 100644
--- a/src/browser/webapi/element/html/Select.zig
+++ b/src/browser/webapi/element/html/Select.zig
@@ -44,8 +44,13 @@ pub fn asConstNode(self: *const Select) *const Node {
     return self.asConstElement().asConstNode();
 }
 
-pub fn getValue(self: *Select, frame: *Frame) []const u8 {
-    // Return value of first selected option, or first option if none selected
+// Resolves the option whose selectedness contributes to the select's value
+// per HTML §form-elements§selectedness-setting-algorithm: an explicitly
+// selected non-disabled option, falling back to the first non-disabled
+// option in tree order. Returns null if there is no candidate (zero options
+// or every option disabled), in which case the select has no selectedness
+// and contributes no entry to a FormData set.
+pub fn effectiveOption(self: *Select) ?*Option {
     var first_option: ?*Option = null;
     var iter = self.asNode().childrenIterator();
     while (iter.next()) |child| {
@@ -55,14 +60,17 @@ pub fn getValue(self: *Select, frame: *Frame) []const u8 {
         }
 
         if (option.getSelected()) {
-            return option.getValue(frame);
+            return option;
         }
         if (first_option == null) {
             first_option = option;
         }
     }
-    // No explicitly selected option, return first option's value
-    if (first_option) |opt| {
+    return first_option;
+}
+
+pub fn getValue(self: *Select, frame: *Frame) []const u8 {
+    if (self.effectiveOption()) |opt| {
         return opt.getValue(frame);
     }
     return "";
diff --git a/src/browser/webapi/net/FormData.zig b/src/browser/webapi/net/FormData.zig
index 0258dd8e..cd8584da 100644
--- a/src/browser/webapi/net/FormData.zig
+++ b/src/browser/webapi/net/FormData.zig
@@ -196,18 +196,12 @@ fn collectForm(arena: Allocator, form_: ?*Form, submitter_: ?*Element, frame: *F
 
             if (element.is(Form.Select)) |select| {
                 if (select.getMultiple() == false) {
-                    // Per the HTML spec, a single-select's selectedness comes
-                    // from an explicitly-selected option, falling back to the
-                    // first non-disabled option in tree order. With no options
-                    // (or only disabled ones), nothing is selected and no
-                    // entry is appended.
-                    var children = select.asNode().childrenIterator();
-                    const has_candidate = while (children.next()) |child| {
-                        const option = child.is(Form.Select.Option) orelse continue;
-                        if (!option.getDisabled()) break true;
-                    } else false;
-                    if (!has_candidate) continue;
-                    break :blk select.getValue(frame);
+                    // Per the HTML spec, a single-select with no selectedness
+                    // candidate (zero options or every option disabled)
+                    // contributes no entry. Otherwise emit the candidate's
+                    // value.
+                    const opt = select.effectiveOption() orelse continue;
+                    break :blk opt.getValue(frame);
                 }
 
                 var options = try select.getSelectedOptions(frame);