fix: clip input text, selection, and caret to the field viewport

ui/text_input.v

@@ -63,3 +63,15 @@ pub fn text_input(config TextInputConfig) !Element {
 	}
 	return field
 }
+
+// text_field_content_rect is the immediate renderer's single-line viewport.
+// Keep a small vertical inset for the focus border and clamp narrow controls
+// rather than passing negative sizes to the graphics backend.
+fn text_field_content_rect(frame Rect, padding_left f64) Rect {
+	left := if padding_left > 0 { padding_left } else { 0.0 }
+	return rect(frame.x + left, frame.y + 2, if frame.width > left + 8 {
+		frame.width - left - 8
+	} else {
+		0.0
+	}, if frame.height > 4 { frame.height - 4 } else { 0.0 })
+}

ui/text_input_test.v

@@ -55,3 +55,20 @@ fn test_text_input_rejects_multiline_password_mode() {
 		assert err.msg().contains('single-line')
 	}
 }
+
+fn test_single_line_content_viewport_respects_padding_and_parent_clip() {
+	content := text_field_content_rect(rect(20, 30, 100, 36), 12)
+	assert content == rect(32, 32, 80, 32)
+	assert intersect_rect(content, rect(40, 40, 200, 100)) == rect(40, 40, 72, 24)
+	assert intersect_rect(content, rect(0, 0, 10, 10)).width == 0
+	assert text_field_content_rect(rect(20, 30, 100, 36), -5) == rect(20, 32, 92, 32)
+}
+
+fn test_single_line_content_viewport_clamps_empty_and_tiny_controls() {
+	for frame in [rect(0, 0, 0, 0), rect(0, 0, 10, 3), rect(0, 0, -10, -10)] {
+		content := text_field_content_rect(frame, 12)
+		assert content.width == 0
+		assert content.height == 0
+	}
+	assert text_field_content_rect(rect(0, 0, 20, 36), 30).width == 0
+}

ui/ui_immediate.c.v

@@ -1925,29 +1925,37 @@ fn page_focused_text_area(direction int) {
 				is_focused := g_focused_field == el.id
 				draw_control_surface(ctx, x, y, el.frame.width, el.frame.height, el.box,
 					is_focused, el.enabled)
-				if is_focused && !editor.selection.collapsed() {
-					draw_text_field_selection(ctx, display_text, editor.selection, x + padding_left,
-						y, content_width, el.frame.height, el.text_style)
-				}
-				if current_text.len > 0 {
-					draw_editable_text(ctx, display_text, x + padding_left, y, content_width, el.frame.height, el.text_style)
-				} else if el.placeholder.len > 0 {
-					placeholder_style := TextStyle{
-						...el.text_style
-						color: 0x999999
+				// Editable text is not ellipsized: keep its full value for caret and
+				// selection measurement, but paint only inside the input's viewport.
+				content_clip := intersect_rect(text_field_content_rect(rect(x, y,
+					el.frame.width, el.frame.height), padding_left), clip)
+				if content_clip.width > 0 && content_clip.height > 0 {
+					apply_clip(ctx, content_clip)
+					if is_focused && !editor.selection.collapsed() {
+						draw_text_field_selection(ctx, display_text, editor.selection, x + padding_left,
+							y, content_width, el.frame.height, el.text_style)
 					}
-					draw_editable_text(ctx, el.placeholder, x + padding_left, y, content_width, el.frame.height, placeholder_style)
-				}
-				if is_focused {
-					before := editor.text.runes()[..editor.selection.caret].string()
-					caret_text := text_field_display_text(before, el.secure)
-					text_w := f64(ctx.text_width(caret_text))
-					text_origin := text_field_aligned_text_origin(x + padding_left, content_width,
-						f64(ctx.text_width(display_text)), el.text_style.align)
-					cursor_x := text_origin + text_w
-					cursor_y := y + el.frame.height * 0.2
-					cursor_h := el.frame.height * 0.6
-					draw_rect(ctx, cursor_x, cursor_y, 2, cursor_h, el.text_style.color, 0)
+					if current_text.len > 0 {
+						draw_editable_text(ctx, display_text, x + padding_left, y, content_width, el.frame.height, el.text_style)
+					} else if el.placeholder.len > 0 {
+						placeholder_style := TextStyle{
+							...el.text_style
+							color: 0x999999
+						}
+						draw_editable_text(ctx, el.placeholder, x + padding_left, y, content_width, el.frame.height, placeholder_style)
+					}
+					if is_focused {
+						before := editor.text.runes()[..editor.selection.caret].string()
+						caret_text := text_field_display_text(before, el.secure)
+						text_w := f64(ctx.text_width(caret_text))
+						text_origin := text_field_aligned_text_origin(x + padding_left, content_width,
+							f64(ctx.text_width(display_text)), el.text_style.align)
+						cursor_x := text_origin + text_w
+						cursor_y := y + el.frame.height * 0.2
+						cursor_h := el.frame.height * 0.6
+						draw_rect(ctx, cursor_x, cursor_y, 2, cursor_h, el.text_style.color, 0)
+					}
+					apply_clip(ctx, clip)
 				}
 				if el.enabled && !el.readonly {
 					add_hit_target(HitTarget{