fix conv export (#2265)

python/tests/test_export_import.py

@@ -6,6 +6,7 @@ import tempfile
 import unittest
 
 import mlx.core as mx
+import mlx.nn as nn
 import mlx_tests
 
 
@@ -312,6 +313,39 @@ class TestExportImport(mlx_tests.MLXTestCase):
         out = imported_fun(x, y, z)[0]
         self.assertTrue(mx.array_equal(expected, out))
 
+    def test_export_conv(self):
+        path = os.path.join(self.test_dir, "fn.mlxfn")
+
+        class Model(nn.Module):
+            def __init__(self):
+                super().__init__()
+                self.c1 = nn.Conv2d(
+                    3, 16, kernel_size=3, stride=1, padding=1, bias=False
+                )
+                self.c2 = nn.Conv2d(
+                    16, 16, kernel_size=3, stride=2, padding=1, bias=False
+                )
+                self.c3 = nn.Conv2d(
+                    16, 16, kernel_size=3, stride=1, padding=2, bias=False
+                )
+
+            def __call__(self, x):
+                return self.c3(self.c2(self.c1(x)))
+
+        model = Model()
+        mx.eval(model.parameters())
+
+        def forward(x):
+            return model(x)
+
+        input_data = mx.random.normal(shape=(4, 32, 32, 3))
+        mx.export_function(path, forward, input_data)
+
+        imported_fn = mx.import_function(path)
+        out = imported_fn(input_data)[0]
+        expected = forward(input_data)
+        self.assertTrue(mx.allclose(expected, out))
+
 
 if __name__ == "__main__":
     unittest.main()