Fixes #7 - ignore any exceptions raised when importing from pip

CHANGES.rst

@@ -4,6 +4,9 @@ Changelog
 Unreleased Changes
 ------------------
 
+**Important:**
+
+* Fix `Issue #7 <https://github.com/jantman/versionfinder/issues/7>`_ where certain new versions of pip throw an AttributeError on import if running in Lambda (or other environments where ``sys.stdin`` is ``None``).
 * Stop testing Python 3.3 and drop official support for it.
 * Multiple pip10 fixes.
 * Test fixes:

versionfinder/versionfinder.py

@@ -46,27 +46,33 @@
 
 from .versioninfo import VersionInfo
 
+# Note: we catch all exceptions here because of
+# https://github.com/jantman/versionfinder/issues/7 - some pip versions
+# throw an import-time AttributeError when running in Lambda, or other
+# environments where sys.stdin is None. Per that issue, the right thing to
+# do is never fail if pip can't be imported.
+# This was fixed in https://github.com/pypa/pip/pull/7118 / pip 19.3
 try:
     from pip._internal.operations.freeze import FrozenRequirement
-except (ImportError, KeyError):
+except Exception:
     try:
         from pip._internal import FrozenRequirement
-    except (ImportError, KeyError):
+    except Exception:
         try:
             from pip import FrozenRequirement
-        except (ImportError, KeyError):
+        except Exception:
             # this is used within try blocks; NBD if they fail
             pass
 
 try:
     from pip._internal.utils.misc import get_installed_distributions
-except (ImportError, KeyError):
+except Exception:
     try:
         from pip._internal import get_installed_distributions
-    except (ImportError, KeyError):
+    except Exception:
         try:
             from pip import get_installed_distributions
-        except (ImportError, KeyError):
+        except Exception:
             # this is used within try blocks; NBD if they fail
             pass