Move specialized Windows behavior to a specialized subclass

--HG--
extra : rebase_source : f56a411c3cace611952133b96a48ed92888f75a1

setuptools/command/easy_install.py

@@ -1799,20 +1799,35 @@ class ScriptWriter(object):
         """
         Yield write_script() argument tuples for a distribution's entrypoints
         """
+        gen_class = cls.get_writer(wininst)
         spec = str(dist.as_requirement())
         header = get_script_header("", executable, wininst)
         for type_ in 'console', 'gui':
             group = type_ + '_scripts'
             for name, ep in dist.get_entry_map(group).items():
-                script_text = cls.template % locals()
-                for res in cls._get_script_args(type_, name, header,
-                        script_text, wininst):
+                script_text = gen_class.template % locals()
+                for res in gen_class._get_script_args(type_, name, header,
+                        script_text):
                     yield res
 
     @classmethod
-    def _get_script_args(cls, type_, name, dist, executable, wininst):
-        if sys.platform=='win32' or wininst:
-            # On Windows/wininst, add a .py extension and an .exe launcher
+    def get_writer(cls, force_windows):
+        if force_windows or sys.platform=='win32':
+            return WindowsScriptWriter
+        return cls
+
+    @classmethod
+    def _get_script_args(cls, type_, name, header, script_text):
+        # Simply write the stub with no extension.
+        yield (name, header+script_text)
+
+
+class WindowsScriptWriter(ScriptWriter):
+    @classmethod
+    def _get_script_args(cls, type_, name, header, script_text):
+        """
+        For Windows, add a .py extension and an .exe launcher
+        """
         if type_=='gui':
             launcher_type = 'gui'
             ext = '-script.pyw'
@@ -1840,10 +1855,7 @@ class ScriptWriter(object):
             #  See Distribute #143 for details.
             m_name = name + '.exe.manifest'
             yield (m_name, load_launcher_manifest(name), 't')
-        else:
-            # On other platforms, we assume the right thing to do is to
-            # just write the stub with no extension.
-            yield (name, header+script_text)
+
 
 # for backward-compatibility
 get_script_args = ScriptWriter.get_script_args