Allow to run platformio directly from the bin folder

platformio/builder/main.py

@@ -5,11 +5,19 @@ try:
     from platformio import util
 except ImportError:
     import sys
-    for _path in sys.path:
-        if "platformio" in _path:
-            sys.path.insert(0, _path[:_path.rfind("platformio") - 1])
+    for p in sys.path:
+        _new_path = None
+        if not p.endswith("site-packages") and "site-packages" in p:
+            _new_path = p[:p.rfind("site-packages") + 13]
+        elif "platformio" in p:
+            _new_path = p[:p.rfind("platformio") - 1]
+        if _new_path and _new_path not in sys.path:
+            sys.path.insert(0, _new_path)
+        try:
+            from platformio import util
             break
-    from platformio import util
+        except ImportError:
+            pass
 
 import json
 from os import environ

platformio/platforms/base.py

@@ -1,9 +1,10 @@
 # Copyright (C) Ivan Kravets <me@ikravets.com>
 # See LICENSE for details.
 
+import os
 import re
+import sys
 from imp import load_source
-from os import listdir
 from os.path import isdir, isfile, join
 
 import click
@@ -152,7 +153,7 @@ class PlatformFactory(object):
             pdir = join(d, "platforms")
             if not isdir(pdir):
                 continue
-            for p in sorted(listdir(pdir)):
+            for p in sorted(os.listdir(pdir)):
                 if (p in ("__init__.py", "base.py") or not
                         p.endswith(".py")):
                     continue
@@ -371,6 +372,20 @@ class BasePlatform(object):
 
         self._found_error = False
         try:
+            # test that SCons is installed correctly
+            try:
+                r = util.exec_command(["scons", "--version"])
+                assert r['returncode'] == 0
+            except (OSError, AssertionError):
+                for p in sys.path:
+                    try:
+                        r = util.exec_command([join(p, "scons"), "--version"])
+                        assert r['returncode'] == 0
+                        os.environ['PATH'] += os.pathsep + p
+                        break
+                    except (OSError, AssertionError):
+                        pass
+
             result = util.exec_command(
                 [
                     "scons",