Fail if Specified Interpreter Not Found

(Do NOT use basepython as a fallback)

This is intended to remedy these two github issues:

tox-dev#882
tox-dev#1484

by :user: jackdesert

Author: Jack Desert

CONTRIBUTORS

@@ -46,6 +46,7 @@ Igor Duarte Cardoso
 Ilya Kulakov
 Ionel Maries Cristian
 Itxaka Serrano
+Jack Desert
 Jake Windle
 Jannis Leidel
 Jesse Schwartzentruber

src/tox/interpreters/unix.py

@@ -1,4 +1,5 @@
 from __future__ import unicode_literals
+import sys
 
 import tox
 
@@ -8,12 +9,15 @@
 
 @tox.hookimpl
 def tox_get_python_executable(envconfig):
+    """
+    Return path to specified interpreter.
+    If not available, exit(1).
+    """
     spec, path = base_discover(envconfig)
-    if path is not None:
+
+    if path is None:
+        print('envname {} not found'.format(envconfig.envname))
+        sys.exit(1)
+    else:
         return path
-    # 3. check if the literal base python
-    candidates = [envconfig.basepython]
-    # 4. check if the un-versioned name is good
-    if spec.name is not None and spec.name != envconfig.basepython:
-        candidates.append(spec.name)
-    return check_with_path(candidates, spec)
+~