ci: refactor conda tests, from 6 to 5 (~5 min saved)

With this commit, we combine testing the default python version
installation into the default R version installation test.

Author: consideRatio

tests/conda/py-postbuild/README.rst

@@ -0,0 +1,6 @@
+Default R, default Python, and a postBuild file
+-----------------------------------------------
+
+We test the default R and Python version set by repo2docker as used when an
+environment.yml file is provided without a ``python`` or ``r-base`` dependency
+pinned, and the use of a ``postBuild`` file.

tests/conda/py-postbuild/environment.yml

@@ -1,3 +1,4 @@
 dependencies:
+  - pytest
   - r-base
   - r-digest

tests/conda/py-postbuild/verify

@@ -8,3 +8,5 @@ R -e "library('digest')"
 # Fail if version is not at least 4.2
 R --version
 R -e 'if (!(version$major == "4" && as.double(version$minor) >= 2)) quit("yes", 1)'
+
+pytest --verbose --color=yes ./verify.py

tests/conda/r-postbuild/README.rst

@@ -4,14 +4,12 @@
 
 
 def test_sys_version():
+    """The default python version should be 3.7"""
     assert sys.version_info[:2] == (3, 7)
 
 
-def test_numpy():
-    import numpy
-
-
 def test_there():
+    """there is to be installed via postBuild"""
     import there
 
 

tests/conda/r/environment.yml renamed to tests/conda/r-postbuild/environment.yml

@@ -10,8 +10,8 @@
 assert sys.executable.startswith("/srv/conda/"), sys.executable
 
 # Repo should be in /srv/repo
-assert os.path.exists("/srv/repo/verify")
-assert os.path.abspath(__file__) == "/srv/repo/verify"
+assert os.path.exists("/srv/repo/verify.py")
+assert os.path.abspath(__file__) == "/srv/repo/verify.py"
 
 # Repo should be writable
 assert os.access("/srv/repo", os.W_OK)