RF: Move platform id gen code to function for reuse

manifest_rules/generate_environment_files.py

@@ -18,6 +18,7 @@ import               sys
 
 from fsl_ci.conda         import  get_channel_packages
 from manifest_rules.utils import (load_release_info,
+                                  get_platform_identifiers,
                                   generate_environment_file_name,
                                   generate_development_version_identifier)
 
@@ -87,14 +88,9 @@ def generate_variants(release_info):
     """Generate a list of (platform, cudaver) pairs for which an environment
     file should be generated. For non-CUDA environments, cudaver will be None.
     """
-    cudas      = [None] + list(release_info['cuda'])
-    platforms  = os.environ.get('FSLCONDA_PLATFORMS', None)
-    if platforms is None:
-        platforms = list(release_info['miniconda'].keys())
-    else:
-        platforms = platforms = platforms.split(',')
-
-    variants   = list(it.product(platforms, cudas))
+    cudas     = [None] + list(release_info['cuda'])
+    platforms = get_platform_identifiers(release_info)
+    variants  = list(it.product(platforms, cudas))
 
     # CUDA builds are only supported
     # on linux-64 at this time

manifest_rules/utils.py

@@ -174,6 +174,18 @@ def load_release_info(fsl_release_file):
         return yaml.load(f.read(), Loader=yaml.Loader)
 
 
+def get_platform_identifiers(release_info):
+    """Returns a list of all platform identifiers for which FSL environment
+    files are being generated, e.g. ['linux-64', 'macos-64', 'macos-M1'].
+    """
+    platforms  = os.environ.get('FSLCONDA_PLATFORMS', None)
+    if platforms is None:
+        platforms = list(release_info['miniconda'].keys())
+    else:
+        platforms = platforms.split(',')
+    return platforms
+
+
 @contextlib.contextmanager
 def tempdir():
     """Returns a context manager which creates, changes into, and returns a