add tests

Author: jumerckx

test/ir.jl

@@ -1,4 +1,4 @@
-using MLIR.Dialects: arith
+using MLIR.Dialects: arith, builtin
 using MLIR.IR, LLVM
 
 @testset "operation introspection" begin
@@ -11,3 +11,16 @@ using MLIR.IR, LLVM
         @test IR.get_attribute_by_name(op, "value") |> IR.bool_value
     end
 end
+
+@testset "Module construction from operation" begin
+    IR.context!(IR.Context()) do
+        op = builtin.module_(bodyRegion=IR.Region())
+        mod = IR.Module(op)
+        op = IR.get_operation(mod)
+
+        @test IR.name(op) == "builtin.module"
+
+        # Only a `module` operation can be used to create a module.
+        @test_throws AssertionError IR.Module(arith.constant(; value=true, result=MLIRType(Bool)))
+    end
+end