feat(html): add standard boolean attribute helpers

Co-Authored-By: Virgil <virgil@lethean.io>

docs/architecture.md

@@ -62,6 +62,11 @@ Accessibility-oriented helpers are also provided for common attribute patterns:
 - `AriaInvalid(node, invalid)`
 - `AriaRequired(node, required)`
 - `AriaReadOnly(node, readonly)`
+- `Disabled(node, disabled)`
+- `Checked(node, checked)`
+- `Required(node, required)`
+- `ReadOnly(node, readonly)`
+- `Selected(node, selected)`
 - `TabIndex(node, index)`
 - `AutoFocus(node)`
 - `ID(node, id)`

docs/index.md

@@ -39,7 +39,7 @@ This builds a Header-Content-Footer layout with semantic HTML elements (`<header
 
 | Path | Purpose |
 |------|---------|
-| `node.go` | `Node` interface and all node types: `El`, `Text`, `Raw`, `If`, `Unless`, `Each`, `EachSeq`, `Switch`, `Entitled`, plus `AriaLabel`, `AriaControls`, `AriaHasPopup`, `AriaOwns`, `AriaKeyShortcuts`, `Alt`/`AltText`, `AriaBusy`, `AriaLive`, `AriaAtomic`, `AriaDescription`, `AriaDetails`, `AriaErrorMessage`, `AriaRoleDescription`, `AriaDisabled`, `AriaModal`, `AriaChecked`, `AriaInvalid`, `AriaRequired`, `AriaPressed`, `AriaSelected`, `Hidden`, `TabIndex`, and `AutoFocus` helpers |
+| `node.go` | `Node` interface and all node types: `El`, `Text`, `Raw`, `If`, `Unless`, `Each`, `EachSeq`, `Switch`, `Entitled`, plus `AriaLabel`, `AriaControls`, `AriaHasPopup`, `AriaOwns`, `AriaKeyShortcuts`, `Alt`/`AltText`, `AriaBusy`, `AriaLive`, `AriaAtomic`, `AriaDescription`, `AriaDetails`, `AriaErrorMessage`, `AriaRoleDescription`, `AriaDisabled`, `AriaModal`, `AriaChecked`, `AriaInvalid`, `AriaRequired`, `AriaPressed`, `AriaSelected`, `Hidden`, `Disabled`, `Checked`, `Required`, `ReadOnly`, `Selected`, `TabIndex`, and `AutoFocus` helpers |
 | `layout.go` | HLCRF compositor with semantic HTML elements and ARIA roles |
 | `responsive.go` | Multi-variant breakpoint wrapper (`data-variant` containers, CSS scoping helpers) |
 | `context.go` | Rendering context: identity, locale, entitlements, i18n service |
@@ -52,7 +52,7 @@ This builds a Header-Content-Footer layout with semantic HTML elements (`<header
 
 ## Key Concepts
 
-**Node tree** -- All renderable units implement `Node`, a single-method interface: `Render(ctx *Context) string`. The library composes nodes into trees using `El()` for elements, `Text()` for translated text, and control-flow constructors (`If`, `Unless`, `Each`, `Switch`, `Entitled`), plus accessibility and visibility helpers such as `AriaLabel()`, `AriaControls()`, `AriaHasPopup()`, `AriaOwns()`, `AriaKeyShortcuts()`, `AriaCurrent()`, `AriaBusy()`, `AriaLive()`, `AriaAtomic()`, `AriaDescription()`, `AriaDetails()`, `AriaErrorMessage()`, `AriaRoleDescription()`, `AriaHidden()`, `Hidden()`, `AriaDisabled()`, `AriaModal()`, `AriaChecked()`, `AriaInvalid()`, `AriaRequired()`, `AriaReadOnly()`, and `TabIndex()`.
+**Node tree** -- All renderable units implement `Node`, a single-method interface: `Render(ctx *Context) string`. The library composes nodes into trees using `El()` for elements, `Text()` for translated text, and control-flow constructors (`If`, `Unless`, `Each`, `Switch`, `Entitled`), plus accessibility and visibility helpers such as `AriaLabel()`, `AriaControls()`, `AriaHasPopup()`, `AriaOwns()`, `AriaKeyShortcuts()`, `AriaCurrent()`, `AriaBusy()`, `AriaLive()`, `AriaAtomic()`, `AriaDescription()`, `AriaDetails()`, `AriaErrorMessage()`, `AriaRoleDescription()`, `AriaHidden()`, `Hidden()`, `AriaDisabled()`, `AriaModal()`, `AriaChecked()`, `AriaInvalid()`, `AriaRequired()`, `AriaReadOnly()`, `Disabled()`, `Checked()`, `Required()`, `ReadOnly()`, `Selected()`, and `TabIndex()`.
 
 **HLCRF Layout** -- A five-slot compositor that maps to semantic HTML: `<header>` (H), `<aside>` (L/R), `<main>` (C), `<footer>` (F). The variant string controls which slots render: `"HLCRF"` for all five, `"HCF"` for three, `"C"` for content only. Layouts nest: placing a `Layout` inside another layout's slot produces hierarchical `data-block` paths like `L-0-C-0`.
 

node.go

@@ -411,6 +411,61 @@ func Hidden(n Node, hidden bool) Node {
 	return n
 }
 
+// node.go: Disabled sets the HTML disabled attribute on an element node.
+// Example: Disabled(El("button"), true).
+// Disabled follows standard HTML boolean attribute semantics and omits the
+// attribute when false.
+func Disabled(n Node, disabled bool) Node {
+	if disabled {
+		return Attr(n, "disabled", "disabled")
+	}
+	return n
+}
+
+// node.go: Checked sets the HTML checked attribute on an element node.
+// Example: Checked(El("input"), true).
+// Checked follows standard HTML boolean attribute semantics and omits the
+// attribute when false.
+func Checked(n Node, checked bool) Node {
+	if checked {
+		return Attr(n, "checked", "checked")
+	}
+	return n
+}
+
+// node.go: Required sets the HTML required attribute on an element node.
+// Example: Required(El("input"), true).
+// Required follows standard HTML boolean attribute semantics and omits the
+// attribute when false.
+func Required(n Node, required bool) Node {
+	if required {
+		return Attr(n, "required", "required")
+	}
+	return n
+}
+
+// node.go: ReadOnly sets the HTML readonly attribute on an element node.
+// Example: ReadOnly(El("input"), true).
+// ReadOnly follows standard HTML boolean attribute semantics and omits the
+// attribute when false.
+func ReadOnly(n Node, readonly bool) Node {
+	if readonly {
+		return Attr(n, "readonly", "readonly")
+	}
+	return n
+}
+
+// node.go: Selected sets the HTML selected attribute on an element node.
+// Example: Selected(El("option"), true).
+// Selected follows standard HTML boolean attribute semantics and omits the
+// attribute when false.
+func Selected(n Node, selected bool) Node {
+	if selected {
+		return Attr(n, "selected", "selected")
+	}
+	return n
+}
+
 // node.go: AriaExpanded sets the aria-expanded attribute on an element node.
 // Example: AriaExpanded(El("button"), true).
 func AriaExpanded(n Node, expanded bool) Node {

node_test.go

@@ -754,6 +754,86 @@ func TestHiddenHelper(t *testing.T) {
 	}
 }
 
+func TestDisabledHelper(t *testing.T) {
+	ctx := NewContext()
+
+	disabled := Disabled(El("button", Raw("menu")), true)
+	gotDisabled := disabled.Render(ctx)
+	if !strings.Contains(gotDisabled, `disabled="disabled"`) {
+		t.Errorf("Disabled(true) = %q, want disabled=\"disabled\"", gotDisabled)
+	}
+
+	enabled := Disabled(El("button", Raw("menu")), false)
+	gotEnabled := enabled.Render(ctx)
+	if strings.Contains(gotEnabled, `disabled=`) {
+		t.Errorf("Disabled(false) = %q, want no disabled attribute", gotEnabled)
+	}
+}
+
+func TestCheckedHelper(t *testing.T) {
+	ctx := NewContext()
+
+	checked := Checked(El("input"), true)
+	gotChecked := checked.Render(ctx)
+	if !strings.Contains(gotChecked, `checked="checked"`) {
+		t.Errorf("Checked(true) = %q, want checked=\"checked\"", gotChecked)
+	}
+
+	unchecked := Checked(El("input"), false)
+	gotUnchecked := unchecked.Render(ctx)
+	if strings.Contains(gotUnchecked, `checked=`) {
+		t.Errorf("Checked(false) = %q, want no checked attribute", gotUnchecked)
+	}
+}
+
+func TestRequiredHelper(t *testing.T) {
+	ctx := NewContext()
+
+	required := Required(El("input"), true)
+	gotRequired := required.Render(ctx)
+	if !strings.Contains(gotRequired, `required="required"`) {
+		t.Errorf("Required(true) = %q, want required=\"required\"", gotRequired)
+	}
+
+	optional := Required(El("input"), false)
+	gotOptional := optional.Render(ctx)
+	if strings.Contains(gotOptional, `required=`) {
+		t.Errorf("Required(false) = %q, want no required attribute", gotOptional)
+	}
+}
+
+func TestReadOnlyHelper(t *testing.T) {
+	ctx := NewContext()
+
+	readonly := ReadOnly(El("input"), true)
+	gotReadonly := readonly.Render(ctx)
+	if !strings.Contains(gotReadonly, `readonly="readonly"`) {
+		t.Errorf("ReadOnly(true) = %q, want readonly=\"readonly\"", gotReadonly)
+	}
+
+	editable := ReadOnly(El("input"), false)
+	gotEditable := editable.Render(ctx)
+	if strings.Contains(gotEditable, `readonly=`) {
+		t.Errorf("ReadOnly(false) = %q, want no readonly attribute", gotEditable)
+	}
+}
+
+func TestSelectedHelper(t *testing.T) {
+	ctx := NewContext()
+
+	selected := Selected(El("option", Raw("menu")), true)
+	gotSelected := selected.Render(ctx)
+	if !strings.Contains(gotSelected, `selected="selected"`) {
+		t.Errorf("Selected(true) = %q, want selected=\"selected\"", gotSelected)
+	}
+
+	unselected := Selected(El("option", Raw("menu")), false)
+	gotUnselected := unselected.Render(ctx)
+	if strings.Contains(gotUnselected, `selected=`) {
+		t.Errorf("Selected(false) = %q, want no selected attribute", gotUnselected)
+	}
+}
+
 func TestAriaExpandedHelper(t *testing.T) {
 	ctx := NewContext()