Fix amplexe if KNITRO_jll is used

Author: odow

src/KNITRO.jl

@@ -39,7 +39,8 @@ end
 else
     import KNITRO_jll
     if KNITRO_jll.is_available()
-        import KNITRO_jll: libknitro
+        using KNITRO_jll: libknitro, knitroampl
+        const amplexe = knitroampl
     else
         error(
             "Unsupported platform: Use a manual installation by setting " *

test/C_wrapper.jl

@@ -1001,3 +1001,10 @@ end
     KN_free(model)
     @test sprint(show, model) == "KNITRO Problem: NULL\n"
 end
+
+@testset "knitroampl" begin
+    @test occursin(
+        "AMPL/Knitro",
+        sprint(io -> run(pipeline(`$(KNITRO.amplexe()) -v`; stdout = io))),
+    )
+end