Replace "env" pattern by "sysenv" in "platformio.ini" // Resolve #1705

HISTORY.rst

@@ -11,6 +11,8 @@ PlatformIO 3.0
   (`issue #1665 <https://github.com/platformio/platformio-core/issues/1665>`_)
 * Handle "architectures" data from "library.properties" manifest in
   `lib_compat_mode = strict <http://docs.platformio.org/en/page/librarymanager/ldf.html#compatibility-mode>`__
+* Replaced conflicted "env" pattern by "sysenv" for `"platformio.ini" Dynamic Variables" <http://docs.platformio.org/page/projectconf/dynamic_variables.html>`__
+  (`issue #1705 <https://github.com/platformio/platformio-core/issues/1705>`_)
 * Removed "date&time" when processing project with `platformio run <http://docs.platformio.org/page/userguide/cmd_run.html>`__ command
   (`issue #1343 <https://github.com/platformio/platformio-core/issues/1343>`_)
 * Fixed issue with invalid LD script if path contains space

platformio/util.py

@@ -63,7 +63,13 @@ class ProjectConfig(ConfigParser.ConfigParser):
 
     def _re_sub_handler(self, match):
         section, option = match.group(1), match.group(2)
-        if section == "env" and not self.has_section(section):
+        if section in ("env", "sysenv") and not self.has_section(section):
+            if section == "env":
+                click.secho(
+                    "Warning! Access to system environment variable via "
+                    "`${{env.{0}}}` is deprecated. Please use "
+                    "`${{sysenv.{0}}}` instead".format(option),
+                    fg="yellow")
             return os.getenv(option)
         return self.get(section, option)