tests for banded operator

Author: jishnub

test/JacobiTest.jl

@@ -380,8 +380,14 @@ import ApproxFunOrthogonalPolynomials: jacobip
 
         @testset "Multiplication" begin
             xJ = Fun(NormalizedJacobi(1,1))
-            @test (Multiplication(Fun()) * xJ)(0.4) ≈ (0.4)^2
-            @test (Multiplication(Fun(NormalizedChebyshev())) * xJ)(0.4) ≈ (0.4)^2
+            xC = Fun()
+            xNC = Fun(NormalizedChebyshev())
+            @test (Multiplication(xC) * xJ)(0.4) ≈ (0.4)^2
+            @test (Multiplication(xNC) * xJ)(0.4) ≈ (0.4)^2
+            @test ApproxFunBase.isbanded(Multiplication(xC, NormalizedLegendre()))
+            @test ApproxFunBase.isbanded(Multiplication(xNC, NormalizedLegendre()))
+            @test ApproxFunBase.isbanded(Multiplication(xC, NormalizedJacobi(1,1)))
+            @test ApproxFunBase.isbanded(Multiplication(xNC, NormalizedJacobi(1,1)))
         end
     end