added auto height

tests/test_widget.py

@@ -3,8 +3,9 @@ from decimal import Decimal
 
 import pytest
 
+from textual.app import App
 from textual.css.errors import StyleValueError
-from textual.css.scalar import Scalar, Unit
+from textual.geometry import Size
 from textual.widget import Widget
 
 
@@ -32,3 +33,35 @@ def test_widget_set_visible_invalid_string():
         widget.visible = "nope! no widget for me!"
 
     assert widget.visible
+
+
+def test_widget_content_width():
+    class TextWidget(Widget):
+        def __init__(self, text: str, id: str) -> None:
+            self.text = text
+            super().__init__(id=id)
+
+        def render(self) -> str:
+            return self.text
+
+    widget1 = TextWidget("foo", id="widget1")
+    widget2 = TextWidget("foo\nbar", id="widget2")
+    widget3 = TextWidget("foo\nbar\nbaz", id="widget3")
+
+    app = App()
+    app._set_active()
+
+    width = widget1.get_content_width(Size(20, 20), Size(80, 24))
+    height = widget1.get_content_height(Size(20, 20), Size(80, 24), width)
+    assert width == 3
+    assert height == 1
+
+    width = widget2.get_content_width(Size(20, 20), Size(80, 24))
+    height = widget2.get_content_height(Size(20, 20), Size(80, 24), width)
+    assert width == 3
+    assert height == 2
+
+    width = widget3.get_content_width(Size(20, 20), Size(80, 24))
+    height = widget3.get_content_height(Size(20, 20), Size(80, 24), width)
+    assert width == 3
+    assert height == 3