MAINT: Make like= in Python functions strict

Only allow objects that implement __array_function__

4 files changed, 71 insertions, 27 deletions

diff --git a/numpy/core/_asarray.py b/numpy/core/_asarray.py
index a406308f3..ade53eeaf 100644
--- a/numpy/core/_asarray.py
+++ b/numpy/core/_asarray.py
@@ -5,6 +5,7 @@ Functions in the ``as*array`` family that promote array-likes into arrays.
 """
 from .overrides import (
     array_function_dispatch,
+    array_function_dispatch_like,
     set_array_function_like_doc,
     set_module,
 )
@@ -97,7 +98,9 @@ def asarray(a, dtype=None, order=None, *, like=None):
 
     """
     if like is not None:
-        return _asarray_with_like(a, dtype=dtype, order=order, like=like)
+        return array_function_dispatch_like(
+            _asarray_with_like, a, dtype=dtype, order=order, like=like
+        )
 
     return array(a, dtype, copy=False, order=order)
 
@@ -166,7 +169,9 @@ def asanyarray(a, dtype=None, order=None, *, like=None):
 
     """
     if like is not None:
-        return _asanyarray_with_like(a, dtype=dtype, order=order, like=like)
+        return array_function_dispatch_like(
+            _asanyarray_with_like, a, dtype=dtype, order=order, like=like
+        )
 
     return array(a, dtype, copy=False, order=order, subok=True)
 
@@ -223,7 +228,9 @@ def ascontiguousarray(a, dtype=None, *, like=None):
 
     """
     if like is not None:
-        return _ascontiguousarray_with_like(a, dtype=dtype, like=like)
+        return array_function_dispatch_like(
+            _ascontiguousarray_with_like, a, dtype=dtype, like=like
+        )
 
     return array(a, dtype, copy=False, order='C', ndmin=1)
 
@@ -276,7 +283,9 @@ def asfortranarray(a, dtype=None, *, like=None):
 
     """
     if like is not None:
-        return _asfortranarray_with_like(a, dtype=dtype, like=like)
+        return array_function_dispatch_like(
+            _asfortranarray_with_like, a, dtype=dtype, like=like
+        )
 
     return array(a, dtype, copy=False, order='F', ndmin=1)
 
@@ -363,7 +372,8 @@ def require(a, dtype=None, requirements=None, *, like=None):
 
     """
     if like is not None:
-        return _require_with_like(
+        return array_function_dispatch_like(
+            _require_with_like,
             a,
             dtype=dtype,
             requirements=requirements,
diff --git a/numpy/core/numeric.py b/numpy/core/numeric.py
index 25235f738..f0d1f163a 100644
--- a/numpy/core/numeric.py
+++ b/numpy/core/numeric.py
@@ -21,7 +21,9 @@ from .multiarray import (
 from . import overrides
 from . import umath
 from . import shape_base
-from .overrides import set_array_function_like_doc, set_module
+from .overrides import (
+    array_function_dispatch_like, set_array_function_like_doc, set_module
+    )
 from .umath import (multiply, invert, sin, PINF, NAN)
 from . import numerictypes
 from .numerictypes import longlong, intc, int_, float_, complex_, bool_
@@ -198,7 +200,9 @@ def ones(shape, dtype=None, order='C', *, like=None):
 
     """
     if like is not None:
-        return _ones_with_like(shape, dtype=dtype, order=order, like=like)
+        return array_function_dispatch_like(
+            _ones_with_like, shape, dtype=dtype, order=order, like=like
+        )
 
     a = empty(shape, dtype, order)
     multiarray.copyto(a, 1, casting='unsafe')
@@ -334,7 +338,14 @@ def full(shape, fill_value, dtype=None, order='C', *, like=None):
 
     """
     if like is not None:
-        return _full_with_like(shape, fill_value, dtype=dtype, order=order, like=like)
+        return array_function_dispatch_like(
+            _full_with_like,
+            shape,
+            fill_value,
+            dtype=dtype,
+            order=order,
+            like=like,
+        )
 
     if dtype is None:
         fill_value = asarray(fill_value)
@@ -1847,7 +1858,14 @@ def fromfunction(function, shape, *, dtype=float, like=None, **kwargs):
 
     """
     if like is not None:
-        return _fromfunction_with_like(function, shape, dtype=dtype, like=like, **kwargs)
+        return array_function_dispatch_like(
+            _fromfunction_with_like,
+            function,
+            shape,
+            dtype=dtype,
+            like=like,
+            **kwargs,
+        )
 
     args = indices(shape, dtype=dtype)
     return function(*args, **kwargs)
@@ -2168,7 +2186,9 @@ def identity(n, dtype=None, *, like=None):
 
     """
     if like is not None:
-        return _identity_with_like(n, dtype=dtype, like=like)
+        return array_function_dispatch_like(
+            _identity_with_like, n, dtype=dtype, like=like
+        )
 
     from numpy import eye
     return eye(n, dtype=dtype, like=like)
diff --git a/numpy/lib/npyio.py b/numpy/lib/npyio.py
index 805e59bc1..f6b82dbd3 100644
--- a/numpy/lib/npyio.py
+++ b/numpy/lib/npyio.py
@@ -14,7 +14,9 @@ from . import format
 from ._datasource import DataSource
 from numpy.core import overrides
 from numpy.core.multiarray import packbits, unpackbits
-from numpy.core.overrides import set_array_function_like_doc, set_module
+from numpy.core.overrides import (
+    array_function_dispatch_like, set_array_function_like_doc, set_module
+    )
 from numpy.core._internal import recursive
 from ._iotools import (
     LineSplitter, NameValidator, StringConverter, ConverterError,
@@ -899,10 +901,10 @@ def loadtxt(fname, dtype=float, comments='#', delimiter=None,
     """
 
     if like is not None:
-        return _loadtxt_with_like(
-            fname, dtype=dtype, comments=comments, delimiter=delimiter,
-            converters=converters, skiprows=skiprows, usecols=usecols,
-            unpack=unpack, ndmin=ndmin, encoding=encoding,
+        return array_function_dispatch_like(
+            _loadtxt_with_like, fname, dtype=dtype, comments=comments,
+            delimiter=delimiter, converters=converters, skiprows=skiprows,
+            usecols=usecols, unpack=unpack, ndmin=ndmin, encoding=encoding,
             max_rows=max_rows, like=like
         )
 
@@ -1751,15 +1753,15 @@ def genfromtxt(fname, dtype=float, comments='#', delimiter=None,
     """
 
     if like is not None:
-        return _genfromtxt_with_like(
-            fname, dtype=dtype, comments=comments, delimiter=delimiter,
-            skip_header=skip_header, skip_footer=skip_footer,
-            converters=converters, missing_values=missing_values,
-            filling_values=filling_values, usecols=usecols, names=names,
-            excludelist=excludelist, deletechars=deletechars,
-            replace_space=replace_space, autostrip=autostrip,
-            case_sensitive=case_sensitive, defaultfmt=defaultfmt,
-            unpack=unpack, usemask=usemask, loose=loose,
+        return array_function_dispatch_like(
+            _genfromtxt_with_like, fname, dtype=dtype, comments=comments,
+            delimiter=delimiter, skip_header=skip_header,
+            skip_footer=skip_footer, converters=converters,
+            missing_values=missing_values, filling_values=filling_values,
+            usecols=usecols, names=names, excludelist=excludelist,
+            deletechars=deletechars, replace_space=replace_space,
+            autostrip=autostrip, case_sensitive=case_sensitive,
+            defaultfmt=defaultfmt, unpack=unpack, usemask=usemask, loose=loose,
             invalid_raise=invalid_raise, max_rows=max_rows, encoding=encoding,
             like=like
         )
diff --git a/numpy/lib/twodim_base.py b/numpy/lib/twodim_base.py
index 2b4cbdfbb..099fb2960 100644
--- a/numpy/lib/twodim_base.py
+++ b/numpy/lib/twodim_base.py
@@ -8,7 +8,9 @@ from numpy.core.numeric import (
     asarray, where, int8, int16, int32, int64, empty, promote_types, diagonal,
     nonzero
     )
-from numpy.core.overrides import set_array_function_like_doc, set_module
+from numpy.core.overrides import (
+    array_function_dispatch_like, set_array_function_like_doc, set_module
+    )
 from numpy.core import overrides
 from numpy.core import iinfo
 
@@ -203,7 +205,15 @@ def eye(N, M=None, k=0, dtype=float, order='C', *, like=None):
 
     """
     if like is not None:
-        return _eye_with_like(N, M=M, k=k, dtype=dtype, order=order, like=like)
+        return array_function_dispatch_like(
+            _eye_with_like,
+            N,
+            M=M,
+            k=k,
+            dtype=dtype,
+            order=order,
+            like=like
+        )
     if M is None:
         M = N
     m = zeros((N, M), dtype=dtype, order=order)
@@ -405,7 +415,9 @@ def tri(N, M=None, k=0, dtype=float, *, like=None):
 
     """
     if like is not None:
-        return _tri_with_like(N, M=M, k=k, dtype=dtype, like=like)
+        return array_function_dispatch_like(
+            _tri_with_like, N, M=M, k=k, dtype=dtype, like=like
+        )
 
     if M is None:
         M = N