MAINT: minimize_cyipopt: add input validation

cyipopt/scipy_interface.py

@@ -107,9 +107,26 @@ def __init__(self,
             raise ImportError()
         self.obj_hess = None
         self.last_x = None
+
+        # Input validation of user-provided arguments
+        if fun is not None and not callable(fun):
+            raise ValueError('`fun` must be callable.')
+        if not isinstance(args, tuple):
+            args = (args,)
+        kwargs = dict() if kwargs is None else kwargs
+        if not isinstance(kwargs, dict):
+            raise ValueError('`kwargs` must be a dictionary.')
+        if jac is not None and jac not in {True, False} and not callable(jac):
+            raise ValueError('`jac` must be callable or boolean.')
+        if hess is not None and not callable(hess):
+            raise ValueError('`hess` must be callable.')
         if hessp is not None:
-            msg = 'Using hessian matrix times an arbitrary vector is not yet implemented!'
-            raise NotImplementedError(msg)
+            raise NotImplementedError(
+                '`hessp` is not yet supported by Ipopt.`')
+        # TODO: add input validation for `constraints` when adding
+        #  support for instances of new-style constraints (e.g.
+        #  `NonlinearConstraint`) and sequences of constraints.
+
         if hess is not None:
             self.obj_hess = hess
         if jac is None:
@@ -118,8 +135,7 @@ def __init__(self,
         elif jac is True:
             fun = MemoizeJac(fun)
             jac = fun.derivative
-        elif not callable(jac):
-            raise NotImplementedError('jac has to be bool or a function')
+
         self.fun = fun
         self.jac = jac
         self.args = args
@@ -465,6 +481,11 @@ def minimize_ipopt(fun,
         msg = 'Install SciPy to use the `minimize_ipopt` function.'
         raise ImportError(msg)
 
+    res = _minimize_ipopt_iv(fun, x0, args, kwargs, method, jac, hess, hessp,
+                             bounds, constraints, tol, callback, options)
+    (fun, x0, args, kwargs, method, jac, hess, hessp,
+     bounds, constraints, tol, callback, options) = res
+
     _x0 = np.atleast_1d(x0)
 
     lb, ub = get_bounds(bounds)
@@ -533,3 +554,33 @@ def minimize_ipopt(fun,
                           nfev=problem.nfev,
                           njev=problem.njev,
                           nit=problem.nit)
+
+def _minimize_ipopt_iv(fun, x0, args, kwargs, method, jac, hess, hessp,
+                       bounds, constraints, tol, callback, options):
+    # basic input validation for minimize_ipopt that is not included in
+    # IpoptProblemWrapper
+
+    x0 = np.asarray(x0)[()]
+    if not np.issubdtype(x0.dtype, np.number):
+        raise ValueError('`x0` must be a numeric array.')
+
+    if method is not None:  # this will be updated when gh-200 is merged
+        raise NotImplementedError('`method` is not yet supported.`')
+
+    # TODO: add input validation for `bounds` when adding
+    #  support for instances of new-style constraints (e.g. `Bounds`)
+
+    if callback is not None:
+        raise NotImplementedError('`callback` is not yet supported by Ipopt.`')
+
+    if tol is not None:
+        tol = np.asarray(tol)[()]
+        if tol.ndim != 0 or not np.issubdtype(tol.dtype, np.number) or tol <= 0:
+            raise ValueError('`tol` must be a positive scalar.')
+
+    options = dict() if options is None else options
+    if not isinstance(options, dict):
+        raise ValueError('`options` must be a dictionary.')
+
+    return (fun, x0, args, kwargs, method, jac, hess, hessp,
+            bounds, constraints, tol, callback, options)

cyipopt/tests/unit/test_scipy_optional.py

@@ -25,6 +25,58 @@ def test_minimize_ipopt_import_error_if_no_scipy():
         cyipopt.minimize_ipopt(None, None)
 
 
+@pytest.mark.skipif("scipy" not in sys.modules,
+                    reason="Test only valid if Scipy available.")
+def test_minimize_ipopt_input_validation():
+    x0 = 1
+    def f(x):
+        return x**2
+
+    message = "`fun` must be callable."
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt('migratory coconuts', x0)
+
+    message = "`x0` must be a numeric array."
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt(f, 'spamalot')
+
+    message = "`kwargs` must be a dictionary."
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt(f, x0, kwargs='elderberries')
+
+    message = "`method` is not yet supported."
+    with pytest.raises(NotImplementedError, match=message):
+        cyipopt.minimize_ipopt(f, x0, method='a newt')
+
+    message = "`jac` must be callable or boolean."
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt(f, x0, jac='self-perpetuating autocracy')
+
+    message = "`hess` must be callable."
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt(f, x0, hess='farcical aquatic ceremony')
+
+    message = "`hessp` is not yet supported by Ipopt."
+    with pytest.raises(NotImplementedError, match=message):
+        cyipopt.minimize_ipopt(f, x0, hessp='shrubbery')
+
+    message = "`callback` is not yet supported by Ipopt."
+    with pytest.raises(NotImplementedError, match=message):
+        cyipopt.minimize_ipopt(f, x0, callback='a duck')
+
+    message = "`tol` must be a positive scalar."
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt(f, x0, tol=[1, 2, 3])
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt(f, x0, tol='ni')
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt(f, x0, tol=-1)
+
+    message = "`options` must be a dictionary."
+    with pytest.raises(ValueError, match=message):
+        cyipopt.minimize_ipopt(f, x0, options='supreme executive power')
+
+
 @pytest.mark.skipif("scipy" not in sys.modules,
                     reason="Test only valid if Scipy available.")
 def test_minimize_ipopt_if_scipy():