OmaPhoto 1.0.0: the Linux port of Compositor

A layered image editor for Linux and Omarchy, ported from Compositor
(github.com/robbietilton/Compositor), whose Swift source is its
specification. It reads and writes Compositor's .comp projects.

Packages for Ubuntu, Fedora and Arch come from the release workflow;
scripts/install/ holds one install script per distribution family,
and flake.nix serves NixOS.

Co-Authored-By: Claude <noreply@anthropic.com>

tests/SubjectRemovalModelTests.cpp

@@ -0,0 +1,60 @@
+#include "Document/BrushStroke.h"
+#include "Document/SubjectRemoval.h"
+#include <QPainter>
+#include <QTemporaryDir>
+#include <QtTest>
+
+// The model comes from data folders; failures say why.
+class SubjectRemovalModelTests : public QObject {
+    Q_OBJECT
+private slots:
+    void aModelThatFailsIsNamedAndTheNextUseLoadsAgain();
+};
+
+namespace {
+QString failure(const QImage &image)
+{
+    try {
+        SubjectRemoval::run(image, FilterSettings());
+    } catch (const SubjectRemovalError &error) {
+        return error.kind == SubjectRemovalError::Kind::model ? QString::fromUtf8(error.what()) : QStringLiteral("no subject");
+    }
+    return QString();
+}
+}
+
+void SubjectRemovalModelTests::aModelThatFailsIsNamedAndTheNextUseLoadsAgain()
+{
+    QImage image = BrushRaster::context(200, 150, false);
+    image.fill(Qt::white);
+    QPainter painter(&image);
+    painter.setBrush(QColor(217, 26, 26));
+    painter.setPen(Qt::NoPen);
+    painter.drawEllipse(QPointF(100, 75), 40, 40);
+    painter.end();
+    const QByteArray folders = qgetenv("XDG_DATA_DIRS");
+    // No model in the file: ONNX Runtime's words pass on.
+    const QTemporaryDir broken;
+    QVERIFY(QDir(broken.path()).mkpath(QStringLiteral("omaphoto")));
+    QFile garbage(broken.filePath(QStringLiteral("omaphoto/u2net.onnx")));
+    QVERIFY(garbage.open(QIODevice::WriteOnly) && garbage.write("not a model") == 11);
+    garbage.close();
+    qputenv("XDG_DATA_DIRS", broken.path().toUtf8());
+    QString said = failure(image);
+    QVERIFY2(said.startsWith(QStringLiteral("Remove Background could not use its model: ")) && said.size() > 60, qPrintable(said));
+    // No file at all: every folder looked in is named.
+    const QTemporaryDir empty;
+    qputenv("XDG_DATA_DIRS", empty.path().toUtf8());
+    said = failure(image);
+    QVERIFY2(said.startsWith(QStringLiteral("Remove Background could not use its model: omaphoto/u2net.onnx is in no data folder (")), qPrintable(said));
+    QVERIFY2(said.contains(empty.path()), qPrintable(said));
+    // Back in its folder, the next use loads it.
+    if (folders.isEmpty())
+        qunsetenv("XDG_DATA_DIRS");
+    else
+        qputenv("XDG_DATA_DIRS", folders);
+    QVERIFY(failure(image).isEmpty());
+}
+
+QTEST_GUILESS_MAIN(SubjectRemovalModelTests)
+#include "SubjectRemovalModelTests.moc"