S4 Tier 0: the bank plays — VST3 marshals MIDI to the S3 core, reads the live bank + resolves WAV the M4 way, mono downmix, lock-free load handoff, LICE sample-pick

tests/test_editor_geometry.cpp

@@ -131,6 +131,63 @@ static void testHitTestMatchesDrawnButton() {
     }
 }
 
+// --- sample list (S4) ---------------------------------------------------------
+
+static void testSampleRowRectStacks() {
+    const EditorLayout L = layoutEditor(400, 260);
+    const Rect r0 = sampleRowRect(L, 0);
+    const Rect r1 = sampleRowRect(L, 1);
+    // Row 0 starts at the canvas top and spans its full width.
+    CHECK(r0.top == L.canvas.top);
+    CHECK(r0.left == L.canvas.left && r0.right == L.canvas.right);
+    CHECK(r0.height() == kSampleRowHeight);
+    // Row 1 sits directly below row 0 (no gap, no overlap).
+    CHECK(r1.top == r0.bottom);
+    CHECK(r1.height() == kSampleRowHeight);
+    // A negative index is an empty rect.
+    CHECK(sampleRowRect(L, -1).width() == 0 && sampleRowRect(L, -1).height() == 0);
+}
+
+static void testSampleRowHitTestMapsClickToRow() {
+    const EditorLayout L = layoutEditor(400, 260);
+    const int rows = 5;
+    // A click in the vertical middle of row 2 resolves to index 2.
+    const Rect r2 = sampleRowRect(L, 2);
+    const int midY = (r2.top + r2.bottom) / 2;
+    CHECK(sampleRowHitTest(L, rows, 200, midY) == 2);
+    // Row 0's top-left corner hits row 0.
+    const Rect r0 = sampleRowRect(L, 0);
+    CHECK(sampleRowHitTest(L, rows, r0.left, r0.top) == 0);
+}
+
+static void testSampleRowHitTestMisses() {
+    const EditorLayout L = layoutEditor(400, 260);
+    const int rows = 3;
+    // Above the first row (in the title bar) -> no row.
+    CHECK(sampleRowHitTest(L, rows, 200, L.titleBar.top) == -1);
+    // Below the last row -> no row.
+    const Rect last = sampleRowRect(L, rows - 1);
+    CHECK(sampleRowHitTest(L, rows, 200, last.bottom + 1) == -1);
+    // Left of the canvas -> no row.
+    CHECK(sampleRowHitTest(L, rows, L.canvas.left - 1, last.top) == -1);
+    // Zero rows -> always -1.
+    CHECK(sampleRowHitTest(L, 0, 200, L.canvas.top + 1) == -1);
+}
+
+// The drawn-row <-> hit-test agreement: every pixel inside a row rect must resolve to
+// that row's index (the same load-bearing invariant as the button).
+static void testSampleRowHitTestMatchesDrawnRows() {
+    const EditorLayout L = layoutEditor(320, 200);
+    const int rows = 4;
+    for (int i = 0; i < rows; ++i) {
+        const Rect r = sampleRowRect(L, i);
+        if (r.top >= L.canvas.bottom) break;  // clipped rows aren't clickable targets
+        const int y = (r.top + r.bottom) / 2;
+        if (y >= L.canvas.bottom) continue;
+        CHECK(sampleRowHitTest(L, rows, r.left + 1, y) == i);
+    }
+}
+
 int main() {
     testContainsHalfOpen();
     testContainsDegenerate();
@@ -141,6 +198,10 @@ int main() {
     testHitTestMissesNonButton();
     testHitTestButtonBoundary();
     testHitTestMatchesDrawnButton();
+    testSampleRowRectStacks();
+    testSampleRowHitTestMapsClickToRow();
+    testSampleRowHitTestMisses();
+    testSampleRowHitTestMatchesDrawnRows();
 
     if (g_fail == 0) std::printf("editor_geometry: all tests passed\n");
     return g_fail != 0;