Closes https://github.com/ppy/osu/issues/32908.
Have you ever been in a situation wherein you find out you fixed a bug
that you didn't know existed, but that makes *another* bug appear
because it was relying on the other bug? This is where I'm at right now.
But, to start from the top.
`TextFlowContainer.Text` (the setter) is a convenience property that you
use to set the text in one go. Internally it uses `AddText()`:
https://github.com/ppy/osu-framework/blob/681900ffb70adfeede4e3fa32a69da66252691ee/osu.Framework/Graphics/Containers/TextFlowContainer.cs#L81-L94
`AddText()`'s xmldoc says:
The \n character will create a new paragraph, not just a line break.
If you need \n to be a line break, use <see cref="AddParagraph{TSpriteText}(LocalisableString, Action{TSpriteText})"/> instead.
https://github.com/ppy/osu-framework/blob/681900ffb70adfeede4e3fa32a69da66252691ee/osu.Framework/Graphics/Containers/TextFlowContainer.cs#L226-L239
That's right. This portion of xmldoc was *straight up false* and
*silently broken* before https://github.com/ppy/osu-framework/pull/6556.
If you want to check that out yourself, apply the following patch to
framework:
diff --git a/osu.Framework.Tests/Visual/Containers/TestSceneTextFlowContainer.cs b/osu.Framework.Tests/Visual/Containers/TestSceneTextFlowContainer.cs
index 464f47c2c..e1ad521a7 100644
--- a/osu.Framework.Tests/Visual/Containers/TestSceneTextFlowContainer.cs
+++ b/osu.Framework.Tests/Visual/Containers/TestSceneTextFlowContainer.cs
@@ -180,6 +180,22 @@ public void TestAlignmentIsCorrectWhenLineBreaksAtLastWordOfParagraph(Anchor tex
});
}
+ [Test]
+ public void TestSetTextWithNewLine()
+ {
+ AddStep("set text", () => textContainer.Text = "this text\nhas a newline");
+ AddStep("clear and add text", () =>
+ {
+ textContainer.Clear();
+ textContainer.AddText("this text\nhas a newline");
+ });
+ AddStep("clear and add paragraph", () =>
+ {
+ textContainer.Clear();
+ textContainer.AddParagraph("this text\nhas a newline");
+ });
+ }
+
private void assertSpriteTextCount(int count)
=> AddAssert($"text flow has {count} sprite texts", () => textContainer.ChildrenOfType<SpriteText>().Count() == count);
On `master`, there will be a difference between the first two steps, and
the third. On 2025.321.0, *there will be none*.
My working theory as to why this was always busted is that the
corresponding code that was there before in
https://github.com/bdach/osu-framework/blob/c31a48178889ca2f9b4d257d2d64915eee90338a/osu.Framework/Graphics/Containers/TextFlowContainer.cs#L454-L458
just straight up ran too late. *The height of the container is being
changed after the flow has laid itself out, without adjusting subsequent
children in any way.*
There is potentially a discussion to be had as to whether the emergent
behaviour of `TextFlowContainer.Text` with respect to `\n` character is
correct, but I'm just going to start with this diff and see what the
reaction is.
Bartłomiej Dach ·
Dean Herbert ·
Michael Bui ·
Jonas Brandstötter ·
Dan Balasescu ·