Add mpremote tests for scaling, roll, and point

Made-with: Cursor

pico/test/test_fill_n.py

@@ -0,0 +1,52 @@
+"""
+On-device test for Presets.fill_n() using mpremote.
+
+Usage (from pico/ dir or project root with adjusted paths):
+
+    mpremote connect <device> cp src/*.py :
+    mpremote connect <device> cp src/patterns/*.py :patterns
+    mpremote connect <device> cp lib/*.py :
+    mpremote connect <device> cp test/test_fill_n.py :
+    mpremote connect <device> run test_fill_n.py
+
+This script:
+  - Instantiates Presets
+  - Calls fill_n() with a simple range
+  - Lets you visually confirm that all strips show the same proportional segment
+    and that equal-length strip pairs have identical lit indices.
+"""
+
+from presets import Presets
+
+
+def main():
+    presets = Presets()
+    presets.load()
+
+    # Choose a simple test range on the reference strip (strip 0).
+    ref_len = presets.strip_length(0)
+    if ref_len <= 0:
+        print("No strips or invalid length; aborting fill_n test.")
+        return
+
+    # Use a central segment so it's easy to see.
+    start = ref_len // 4
+    end = 3 * ref_len // 4
+    print("Running fill_n test from", start, "to", end, "on reference strip 0.")
+
+    color = (0, 50, 0)  # dim green
+
+    # First, clear everything
+    for strip in presets.strips:
+        strip.fill((0, 0, 0))
+        strip.show()
+
+    # Apply fill_n, which will use scale() internally.
+    presets.fill_n(color, start, end)
+
+    print("fill_n test applied; visually inspect strips.")
+
+
+if __name__ == "__main__":
+    main()
+