merge from distutils-revamp branch (step 2)

- fcompiler changes. All flags, executables, etc., should be overridable
  by the user with config_fc (either command line or setup.cfg) or by
  environment variables

1 files changed, 49 insertions, 0 deletions

diff --git a/numpy/distutils/environment.py b/numpy/distutils/environment.py
new file mode 100644
index 000000000..fa4a77905
--- /dev/null
+++ b/numpy/distutils/environment.py
@@ -0,0 +1,49 @@
+import os
+from distutils.dist import Distribution
+
+__metaclass__ = type
+
+class EnvironmentConfig:
+    def __init__(self, distutils_section='DEFAULT', **kw):
+        self._distutils_section = distutils_section
+        self._conf_keys = kw
+        self._conf = None
+        self._hook_handler = None
+
+    def __getattr__(self, name):
+        try:
+            conf_desc = self._conf_keys[name]
+        except KeyError:
+            raise AttributeError(name)
+        return self._get_var(name, conf_desc)
+
+    def get(self, name, default=None):
+        try:
+            conf_desc = self._conf_keys[name]
+        except KeyError:
+            return default
+        var = self._get_var(name, conf_desc)
+        if var is None:
+            var = default
+        return var
+
+    def _get_var(self, name, conf_desc):
+        hook, envvar, confvar = conf_desc
+        var = self._hook_handler(name, hook)
+        if envvar is not None:
+            var = os.environ.get(envvar, var)
+        if confvar is not None and self._conf:
+            var = self._conf.get(confvar, (None, var))[1]
+        return var
+
+    def clone(self, hook_handler):
+        ec = self.__class__(distutils_section=self._distutils_section,
+                            **self._conf_keys)
+        ec._hook_handler = hook_handler
+        return ec
+
+    def use_distribution(self, dist):
+        if isinstance(dist, Distribution):
+            self._conf = dist.get_option_dict(self._distutils_section)
+        else:
+            self._conf = dist