test_transform: simplified get_font_array code

May contribute fixing Test failures with test_transform on NixOS #20

Author: PierreRaybaut

plotpy/tests/items/test_transform.py

@@ -48,8 +48,7 @@ def get_font_array(sz: int, chars: str = DEFAULT_CHARS) -> np.ndarray | None:
     metric = pnt.fontMetrics()
     rct = metric.boundingRect(chars)
     pnt.end()
-    h = rct.height()
-    w = rct.width()
+    h, w = rct.height(), rct.width()
     img = QG.QImage(w, h, QG.QImage.Format_ARGB32)
     paint = QG.QPainter()
     paint.begin(img)
@@ -62,12 +61,11 @@ def get_font_array(sz: int, chars: str = DEFAULT_CHARS) -> np.ndarray | None:
     paint.drawText(0, paint.fontMetrics().ascent(), chars)
     paint.end()
     try:
-        data = img.bits().asstring(img.sizeInBytes())
+        data = img.bits().asstring(h * w * 4)
     except AttributeError:
         data = img.bits()
-    npy = np.frombuffer(data, np.uint8)
-    npy.shape = img.height(), img.bytesPerLine() // 4, 4
-    return npy[:, :, 0]
+    npy: np.ndarray = np.frombuffer(data, np.uint8)
+    return npy.reshape(h, w, 4)[:, :, 0]
 
 
 def write_text_on_array(