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Expand env variables before checking path
Merge pull request #182 from my-personal-forks/fixes

Small fixes
Improve testing tools

- Run tests for active .py file ('Run' build system)
- A few assorted changes
Merge pull request #183 from my-personal-forks/fixes

Improve testing tools
Remove empty line
Merge branch 'master' of https://github.com/dart-lang/dart-sublime-bundle