Add white pawn move gen test

test/test_movegen.py

@@ -1,10 +1,101 @@
 import ctypes
 from test.base import ChessLibTestBase
+from test.chess_ffi import gen_white_pawn_quiet_pushes
+from test.chess_ffi import gen_white_pawn_push_promotions
+from test.chess_ffi import gen_white_pawn_capture_promotions
+from test.chess_ffi import gen_white_pawn_captures
+from test.chess_ffi import Move
+from test.chess_ffi import Board
 
 
+MAX_MOVES = 256
 
 
 class TestMoveGeneration(ChessLibTestBase):
-    @classmethod
-    def setUpClass(cls):
-        pass
+
+
+    def test_quiet_pawn_pushes_white(self):
+        cases = [
+            ("8/pppppppp/8/8/8/8/PPPPPPPP/8 w - - 0 1", 16, "open ranks"),
+            ("8/8/8/8/8/8/P7/8 w - - 0 1", 2, "single pawn open"),
+            ("8/8/8/8/8/p7/P7/8 w - - 0 1", 0, "blocked single enemy"),
+            ("8/8/8/8/8/n7/P7/8 w - - 0 1", 0, "blocked single friendly"),
+            # Although legal move, we have a separate function that calculates this move type.
+            ("8/9P/8/8/8/8/8/8 w - - 0 1", 0, "no promotion push"),
+        ]
+
+        for fen, expected, msg in cases:
+            with self.subTest(msg=msg, fen=fen):
+                cnt = ctypes.c_int(0)
+                moves = (Move * MAX_MOVES)()
+                b = Board()
+
+                self.load_fen(fen, board=b)
+                gen_white_pawn_quiet_pushes(b, moves, ctypes.byref(cnt))
+
+                self.assertEqual(expected, cnt.value)
+
+
+    def test_quiet_pawn_promotions_white(self):
+        cases = [
+            ("8/PPPPPPPP/8/8/8/8/8/8 w - - 0 1", 8, "all open on 7th rank"),
+            ("8/8/7P/8/8/8/8/8 w - - 0 1", 0, "no promotions"),
+            ("7n/7P/8/8/8/8/8/8 w - - 0 1", 0, "blocked by enemy"),
+            ("7N/7P/8/8/8/8/8/8 w - - 0 1", 0, "blocked by friendly"),
+        ]
+
+        for fen, expected, msg in cases:
+            with self.subTest(msg=msg, fen=fen):
+                cnt = ctypes.c_int(0)
+                moves = (Move * MAX_MOVES)()
+                b = Board()
+
+                self.load_fen(fen, board=b)
+                gen_white_pawn_push_promotions(b, moves, ctypes.byref(cnt))
+
+                self.assertEqual(expected, cnt.value)
+
+
+    def test_capture_pawn_promotions_white(self):
+        cases = [
+            ("6n1/7P/8/8/8/8/8/8 w - - 0 1", 1, "one capture"),
+            ("5n1n/6P1/8/8/8/8/8/8 w - - 0 1", 2, "two captures"),
+            ("8/7P/8/8/8/8/8/8 w - - 0 1", 0, "no capture"),
+        ]
+
+        for fen, expected, msg in cases:
+            with self.subTest(msg=msg, fen=fen):
+                cnt = ctypes.c_int(0)
+                moves = (Move * MAX_MOVES)()
+                b = Board()
+
+                self.load_fen(fen, board=b)
+                gen_white_pawn_capture_promotions(b, moves, ctypes.byref(cnt))
+
+                self.assertEqual(expected, cnt.value)
+
+
+    def test_capture_pawn_white(self):
+        cases = [
+            # normal diagonal captures
+            ("8/8/8/3n4/4P3/8/8/8 w - - 0 1", 1, "e4xd5"),
+            ("8/8/8/3n1n2/4P3/8/8/8 w - - 0 1", 2, "e4xd5 and e4xf5"),
+            ("8/8/8/1p6/P7/8/8/8 w - - 0 1", 1, "edge file: a4xb5"),
+            ("8/7P/8/8/8/8/8/8 w - - 0 1", 0, "no capture"),
+
+            # en passant
+            ("8/8/8/3pP3/8/8/8/8 w - d6 0 1", 1, "EP available: e5xd6 e.p. (black pawn on d5)"),
+            ("8/8/5n2/3pP3/8/8/8/8 w - d6 0 1", 2, "EP e5xd6 and normal e5xf6"),
+            ("8/8/8/3p4/8/4P3/8/8 w - d6 0 1", 0, "EP square present but no white pawn can take"),
+        ]
+
+        for fen, expected, msg in cases:
+            with self.subTest(msg=msg, fen=fen):
+                cnt = ctypes.c_int(0)
+                moves = (Move * MAX_MOVES)()
+                b = Board()
+
+                self.load_fen(fen, board=b)
+                gen_white_pawn_captures(b, moves, ctypes.byref(cnt))
+
+                self.assertEqual(expected, cnt.value)