Migration fails on Unity 7 text assets: %UNITY directive before %YAML is read as binary #1

Product

🔤 UniText

Product version

media.lightside.core 4.4.0, media.lightside.unitext 3.30.0

Unity version

Unity 7000.0.0a7, Windows 11

Platforms

🛠️ Editor

Render pipeline

Not relevant

What happened?

Error:
[LightSide] 85 migration error(s) occurred while updating to media.lightside.core 4.4.0, media.lightside.unitext 3.30.0. ...
System.IO.IOException: [LightSide] Migration coverage is incomplete: 'Assets/.../BootstrapConfig.asset' could not be inspected.
---> System.IO.InvalidDataException: The source has neither a Unity YAML header nor supported native binary metadata (format 774900261).
at LightSide.ProjectYamlFiles.InspectNativeMetadata(...) in Editor/Migration/ProjectYamlFiles.cs:line 183
at LightSide.ProjectYamlFiles.ReadSource(...) in Editor/Migration/ProjectYamlFiles.cs:line 159
at LightSide.MigrationIndex.b__0(ScanTarget target) in Editor/Migration/MigrationIndex.cs:line 443

Cause:
Unity 7 writes a format directive line above the YAML header in text assets.

Suggested fix (I’m running it locally as a patch, and migration then completes):
/// Unity 7 writes a %UNITY format directive on the line before it.
static bool OpensYamlDirective(Stream stream)
{
Span header = stackalloc byte[32];
int read = 0, step;
while (read < header.Length && (step = stream.Read(header.Slice(read))) > 0) read += step;

ReadOnlySpan<byte> text = header.Slice(0, read);
if (read >= 3 && header[0] == 0xEF && header[1] == 0xBB && header[2] == 0xBF) text = text.Slice(3);
if (StartsWith(text, "%UNITY "))
{
    var newline = text.IndexOf((byte)'\n');
    if (newline < 0) return false;
    text = text.Slice(newline + 1);
}
return StartsWith(text, "%YAML");

}

static bool StartsWith(ReadOnlySpan bytes, string ascii)
{
if (bytes.Length < ascii.Length) return false;
for (int i = 0; i < ascii.Length; i++)
if (bytes[i] != ascii[i]) return false;
return true;
}

Steps to reproduce

1. Try migration on the Unity 7

Logs

Screenshots, video or a minimal project

No response

Before submitting

• I searched existing issues and this is not a duplicate.
• I removed access tokens and registry URLs from everything I pasted or attached.