Fix test

desc/integrals/singularities.py

@@ -1069,6 +1069,7 @@ def LHS(Phi_mn):
     return B
 
 
+# FIXME: Need to interpolate Phi_mn to Phi_lmn to compute.
 def compute_dPhi_dn(eq, Phi_mn, Phi_trans):
     """Computes ∇Φ ⋅ n on ∂D.
 
@@ -1090,11 +1091,13 @@ def compute_dPhi_dn(eq, Phi_mn, Phi_trans):
 
     """
     Phi_trans.change_derivatives(1)
+    Phi_r = jnp.zeros(Phi_trans.grid.num_nodes)
     Phi_t = Phi_trans.transform(Phi_mn, dt=1)
     Phi_z = Phi_trans.transform(Phi_mn, dz=1)
-    data = eq.compute(["e^theta", "e^zeta", "n_rho"], grid=Phi_trans.grid)
+    data = eq.compute(["e^rho", "e^theta", "e^zeta", "n_rho"], grid=Phi_trans.grid)
     dPhi_dn = dot(
-        Phi_t[:, jnp.newaxis] * data["e^theta"]
+        Phi_r[:, jnp.newaxis] * data["e^rho"]
+        + Phi_t[:, jnp.newaxis] * data["e^theta"]
         + Phi_z[:, jnp.newaxis] * data["e^zeta"],
         data["n_rho"],
     )

tests/test_integrals.py

@@ -759,10 +759,7 @@ def test(G):
             contour = ax.contourf(theta, zeta, Bn)
             ax.set_title(r"$(\nabla \Phi + B_0) \cdot n$ on $\partial D$")
             fig.colorbar(contour, ax=ax)
-            # FIXME: Doesn't pass unless G = 0 for stellarators, indicating some bug
-            #  in the computation of Phi_mn and hence the surface integrals. grad Phi
-            #  is a periodic function, and Phi should be as well so Phi_mn should
-            #  capture Phi.
+            # FIXME: Doesn't pass unless G = 0 for stellarators.
             try:
                 np.testing.assert_allclose(B0n + dPhi_dn, 0, err_msg=f"G = {G}")
             except AssertionError as e: