sage.features: Add sage.libs.singular, features for standard Python packages

src/sage/features/__init__.py

@@ -52,6 +52,19 @@
 As can be seen above, features try to produce helpful error messages.
 """
 
+# *****************************************************************************
+#       Copyright (C) 2016      Julian Rüth
+#                     2018      Jeroen Demeyer
+#                     2018      Timo Kaufmann
+#                     2019-2022 Matthias Koeppe
+#                     2021      Kwankyu Lee
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 from __future__ import annotations
 
 import os

src/sage/features/all.py

@@ -2,6 +2,15 @@
 Enumeration of all defined features
 """
 
+# *****************************************************************************
+#       Copyright (C) 2021 Matthias Koeppe
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 def all_features():
     r"""
     Return an iterable of all features.

src/sage/features/bliss.py

@@ -1,7 +1,18 @@
-# -*- coding: utf-8 -*-
 r"""
 Features for testing the presence of ``bliss``
 """
+
+# *****************************************************************************
+#       Copyright (C) 2016 Julian Rüth
+#                     2018 Jeroen Demeyer
+#                     2021 Matthias Koeppe
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 from . import CythonFeature, PythonModule
 from .join_feature import JoinFeature
 

src/sage/features/cddlib.py

@@ -1,6 +1,16 @@
 r"""
 Feature for testing the presence of ``cddlib``
 """
+
+# *****************************************************************************
+#       Copyright (C) 2022 Matthias Koeppe
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 from . import Executable
 
 

src/sage/features/csdp.py

@@ -3,6 +3,18 @@
 Feature for testing the presence of ``csdp``
 """
 
+# *****************************************************************************
+#       Copyright (C) 2016 Julian Rüth
+#                     2018 Jeroen Demeyer
+#                     2019 David Coudert
+#                     2021 Matthias Koeppe
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 import os
 import re
 import subprocess

src/sage/features/cython.py

@@ -1,8 +1,16 @@
-# -*- coding: utf-8 -*-
 r"""
 Features for testing the presence of ``cython``
 """
 
+# *****************************************************************************
+#       Copyright (C) 2021 Matthias Koeppe
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 from . import CythonFeature
 
 

src/sage/features/databases.py

@@ -1,8 +1,21 @@
-# -*- coding: utf-8 -*-
 r"""
 Features for testing the presence of various databases
 """
 
+# *****************************************************************************
+#       Copyright (C) 2016      Julian Rüth
+#                     2018-2019 Jeroen Demeyer
+#                     2018      Timo Kaufmann
+#                     2020-2022 Matthias Koeppe
+#                     2020-2022 Sebastian Oehms
+#                     2021      Kwankyu Lee
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 
 from . import StaticFile, PythonModule
 from sage.env import (

src/sage/features/dvipng.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 r"""
 Feature for testing the presence of ``dvipng``
 """

src/sage/features/ffmpeg.py

@@ -1,9 +1,8 @@
-# -*- coding: utf-8 -*-
 r"""
 Feature for testing the presence of ``ffmpeg``
 """
 # ****************************************************************************
-#       Copyright (C) 2018 Sebastien Labbe <[email protected]>
+#       Copyright (C) 2018-2022 Sebastien Labbe <[email protected]>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

src/sage/features/gap.py

@@ -1,9 +1,18 @@
-# -*- coding: utf-8 -*-
 r"""
 Features for testing the presence of GAP packages
 """
+# *****************************************************************************
+#       Copyright (C) 2016 Julian Rüth
+#                     2018 Jeroen Demeyer
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
 
-from . import Feature, FeatureTestResult
+from . import Feature, FeatureTestResult, PythonModule
+from .join_feature import JoinFeature
 
 
 class GapPackage(Feature):
@@ -48,3 +57,34 @@ def _is_present(self):
         else:
             return FeatureTestResult(self, False,
                     reason="`{command}` evaluated to `{presence}` in GAP.".format(command=command, presence=presence))
+
+
+class sage__libs__gap(JoinFeature):
+    r"""
+    A :class:`sage.features.Feature` describing the presence of :mod:`sage.libs.gap`
+    (the library interface to GAP) and :mod:`sage.interfaces.gap` (the pexpect
+    interface to GAP). By design, we do not distinguish between these two, in order
+    to facilitate the conversion of code from the pexpect interface to the library
+    interface.
+
+    EXAMPLES::
+
+        sage: from sage.features.gap import sage__libs__gap
+        sage: sage__libs__gap().is_present()                       # optional - sage.libs.gap
+        FeatureTestResult('sage.libs.gap', True)
+    """
+    def __init__(self):
+        r"""
+        TESTS::
+
+            sage: from sage.features.gap import sage__libs__gap
+            sage: isinstance(sage__libs__gap(), sage__libs__gap)
+            True
+        """
+        JoinFeature.__init__(self, 'sage.libs.gap',
+                             [PythonModule('sage.libs.gap.libgap'),
+                              PythonModule('sage.interfaces.gap')])
+
+
+def all_features():
+    return [sage__libs__gap()]

src/sage/features/gfan.py

@@ -2,6 +2,15 @@
 Features for testing the presence of ``gfan``
 """
 
+# *****************************************************************************
+#       Copyright (C) 2022 Matthias Koeppe
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 from . import Executable
 
 

src/sage/features/graph_generators.py

@@ -1,8 +1,20 @@
-# -*- coding: utf-8 -*-
 r"""
 Features for testing the presence of various graph generator programs
 """
 
+# *****************************************************************************
+#       Copyright (C) 2016 Julian Rüth
+#                     2018 Jeroen Demeyer
+#                     2019 Frédéric Chapoton
+#                     2021 Matthias Koeppe
+#                     2021 Kwankyu Lee
+#
+#  Distributed under the terms of the GNU General Public License (GPL)
+#  as published by the Free Software Foundation; either version 2 of
+#  the License, or (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# *****************************************************************************
+
 import os
 import subprocess
 

src/sage/features/graphviz.py

@@ -1,16 +1,18 @@
-# -*- coding: utf-8 -*-
 r"""
 Features for testing the presence of ``graphviz``
 """
+
 # ****************************************************************************
 #       Copyright (C) 2018 Sebastien Labbe <[email protected]>
+#                     2021 Matthias Koeppe
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
 #                  https://www.gnu.org/licenses/
 # ****************************************************************************
+
 from . import Executable
 from .join_feature import JoinFeature
 

src/sage/features/igraph.py

@@ -1,6 +1,17 @@
 r"""
 Check for igraph
 """
+
+# ****************************************************************************
+#       Copyright (C) 2021 Matthias Koeppe
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
+
 from . import PythonModule
 from .join_feature import JoinFeature
 

src/sage/features/imagemagick.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 r"""
 Feature for testing the presence of ``imagemagick``
 
@@ -7,8 +6,9 @@
 ``identify``, ``composite``, ``montage``, ``compare``, etc. could be also
 checked in this module.
 """
+
 # ****************************************************************************
-#       Copyright (C) 2018 Sebastien Labbe <[email protected]>
+#       Copyright (C) 2018-2022 Sebastien Labbe <[email protected]>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

src/sage/features/interfaces.py

@@ -1,6 +1,17 @@
 r"""
 Features for testing whether interpreter interfaces are functional
 """
+
+# ****************************************************************************
+#       Copyright (C) 2021 Matthias Koeppe
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
+
 import importlib
 
 from . import Feature, FeatureTestResult, PythonModule

src/sage/features/internet.py

@@ -2,6 +2,16 @@
 Feature for testing if the Internet is available
 """
 
+# ****************************************************************************
+#       Copyright (C) 2021 Matthias Koeppe
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
+
 from . import Feature, FeatureTestResult
 
 

src/sage/features/join_feature.py

@@ -2,6 +2,17 @@
 Join features
 """
 
+# ****************************************************************************
+#       Copyright (C) 2021-2022 Matthias Koeppe
+#                     2021-2022 Kwankyu Lee
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
+
 from . import Feature, FeatureTestResult
 
 

src/sage/features/kenzo.py

@@ -1,8 +1,20 @@
-# -*- coding: utf-8 -*-
 r"""
 Feature for testing the presence of ``kenzo``
 """
 
+# ****************************************************************************
+#       Copyright (C) 2020 Travis Scrimshaw
+#                     2021 Matthias Koeppe
+#                     2021 Michael Orlitzky
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
+
+
 from . import Feature, FeatureTestResult
 
 class Kenzo(Feature):

src/sage/features/latex.py

@@ -1,9 +1,12 @@
-# -*- coding: utf-8 -*-
 r"""
 Features for testing the presence of ``latex`` and equivalent programs
 """
+
 # ****************************************************************************
 #       Copyright (C) 2021 Sebastien Labbe <[email protected]>
+#                     2021 Matthias Koeppe
+#                     2022 Kwankyu Lee
+#                     2022 Sebastian Oehms
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by