Ensure cursor visible when no placeholder in Input (#1202)

* Ensure cursor visible when no placeholder in Input

* Update CHANGELOG.md

Author: darrenburns

CHANGELOG.md

@@ -39,6 +39,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Fixed issues with animation. Now objects of different types may be animated.
 - Fixed containers with transparent background not showing borders https://github.com/Textualize/textual/issues/1175
 - Fixed auto-width in horizontal containers https://github.com/Textualize/textual/pull/1155
+- Fixed Input cursor invisible when placeholder empty https://github.com/Textualize/textual/pull/1202
 
 ## [0.4.0] - 2022-11-08
 

src/textual/widgets/_input.py

@@ -176,6 +176,10 @@ def render(self) -> RenderableType:
             if self.has_focus:
                 cursor_style = self.get_component_rich_style("input--cursor")
                 if self._cursor_visible:
+                    # If the placeholder is empty, there's no characters to stylise
+                    # to make the cursor flash, so use a single space character
+                    if len(placeholder) == 0:
+                        placeholder = Text(" ")
                     placeholder.stylize(cursor_style, 0, 1)
             return placeholder
         return _InputRenderable(self, self._cursor_visible)