✨ Add pandas recipe (#2100)

* ✨ Add `pandas` recipe

* ✅ Add tests for `pandas` recipe

* ⬆️ Update `pandas` to latest version `v1.0.3`

* 💚 Remove `pandas`'s dependencies from `setup.py`

Since we manage `pandas`'s dependencies from the recipe,
we remove them from `setup.py` because it causes an error when we run
our `CI` tests.

pythonforandroid/recipes/pandas/__init__.py

@@ -0,0 +1,35 @@
+from os.path import join
+
+from pythonforandroid.recipe import CppCompiledComponentsPythonRecipe
+
+
+class PandasRecipe(CppCompiledComponentsPythonRecipe):
+    version = '1.0.3'
+    url = 'https://github.com/pandas-dev/pandas/releases/download/v{version}/pandas-{version}.tar.gz'  # noqa
+
+    depends = ['cython', 'numpy', 'pytz', 'libbz2', 'liblzma']
+    conflicts = ['python2']
+
+    python_depends = ['python-dateutil']
+    patches = ['fix_numpy_includes.patch']
+
+    call_hostpython_via_targetpython = False
+
+    def get_recipe_env(self, arch):
+        env = super(PandasRecipe, self).get_recipe_env(arch)
+        # we need the includes from our installed numpy at site packages
+        # because we need some includes generated at numpy's compile time
+        env['NUMPY_INCLUDES'] = join(
+            self.ctx.get_python_install_dir(), "numpy/core/include",
+        )
+
+        # this flag below is to fix a runtime error:
+        #   ImportError: dlopen failed: cannot locate symbol
+        #   "_ZTVSt12length_error" referenced by
+        #   "/data/data/org.test.matplotlib_testapp/files/app/_python_bundle
+        #   /site-packages/pandas/_libs/window/aggregations.so"...
+        env['LDFLAGS'] += ' -landroid'
+        return env
+
+
+recipe = PandasRecipe()

pythonforandroid/recipes/pandas/fix_numpy_includes.patch

@@ -0,0 +1,31 @@
+--- pandas-1.0.1/setup.py.orig	2020-02-05 17:15:24.000000000 +0100
++++ pandas-1.0.1/setup.py	2020-03-15 13:47:57.612237225 +0100
+@@ -37,11 +37,12 @@ min_cython_ver = "0.29.13"  # note: sync
+
+ setuptools_kwargs = {
+     "install_requires": [
+-        "python-dateutil >= 2.6.1",
+-        "pytz >= 2017.2",
+-        f"numpy >= {min_numpy_ver}",
++        # dependencies managed via p4a's recipe
++        # "python-dateutil >= 2.6.1",
++        # "pytz >= 2017.2",
++        # f"numpy >= {min_numpy_ver}",
+     ],
+-    "setup_requires": [f"numpy >= {min_numpy_ver}"],
++    "setup_requires": [],
+     "zip_safe": False,
+ }
+
+@@ -514,7 +515,10 @@ def maybe_cythonize(extensions, *args, *
+             )
+         raise RuntimeError("Cannot cythonize without Cython installed.")
+
+-    numpy_incl = pkg_resources.resource_filename("numpy", "core/include")
++    if 'NUMPY_INCLUDES' in os.environ:
++        numpy_incl = os.environ['NUMPY_INCLUDES']
++    else:
++        numpy_incl = pkg_resources.resource_filename("numpy", "core/include")
+     # TODO: Is this really necessary here?
+     for ext in extensions:
+         if hasattr(ext, "include_dirs") and numpy_incl not in ext.include_dirs:

tests/recipes/test_pandas.py

@@ -0,0 +1,51 @@
+import unittest
+
+from os.path import join
+from unittest import mock
+
+from tests.recipes.recipe_lib_test import RecipeCtx
+
+
+class TestPandasRecipe(RecipeCtx, unittest.TestCase):
+    """
+    TestCase for recipe :mod:`~pythonforandroid.recipes.pandas`
+    """
+    recipe_name = "pandas"
+
+    @mock.patch("pythonforandroid.recipe.Recipe.check_recipe_choices")
+    @mock.patch("pythonforandroid.build.ensure_dir")
+    @mock.patch("pythonforandroid.archs.glob")
+    @mock.patch("pythonforandroid.archs.find_executable")
+    def test_get_recipe_env(
+        self,
+        mock_find_executable,
+        mock_glob,
+        mock_ensure_dir,
+        mock_check_recipe_choices,
+    ):
+        """
+        Test that method
+        :meth:`~pythonforandroid.recipes.pandas.PandasRecipe.get_recipe_env`
+        returns the expected flags
+        """
+
+        mock_find_executable.return_value = (
+            "/opt/android/android-ndk/toolchains/"
+            "llvm/prebuilt/linux-x86_64/bin/clang"
+        )
+        mock_glob.return_value = ["llvm"]
+        mock_check_recipe_choices.return_value = sorted(
+            self.ctx.recipe_build_order
+        )
+        numpy_includes = join(
+            self.ctx.get_python_install_dir(), "numpy/core/include",
+        )
+        env = self.recipe.get_recipe_env(self.arch)
+        self.assertIn(numpy_includes, env["NUMPY_INCLUDES"])
+        self.assertIn(" -landroid", env["LDFLAGS"])
+
+        # make sure that the mocked methods are actually called
+        mock_glob.assert_called()
+        mock_ensure_dir.assert_called()
+        mock_find_executable.assert_called()
+        mock_check_recipe_choices.assert_called()