1 files changed, 68 insertions, 0 deletions
diff --git a/Library/Homebrew/compat/requirements/python_requirement.rb b/Library/Homebrew/compat/requirements/python_requirement.rb
new file mode 100644
index 000000000..3215d0a6c
--- /dev/null
+++ b/Library/Homebrew/compat/requirements/python_requirement.rb
@@ -0,0 +1,68 @@
+require "language/python"
+
+class PythonRequirement < Requirement
+  fatal true
+  default_formula "python"
+
+  satisfy build_env: false do
+    python = which_python
+    next unless python
+    next unless short_version
+    # Always use Python 2.7 for consistency on older versions of Mac OS X.
+    short_version == Version.create("2.7")
+  end
+
+  env do
+    if !system_python? && short_version == Version.create("2.7")
+      ENV.prepend_path "PATH", which_python.dirname
+    end
+
+    # Homebrew Python should take precedence over other Pythons in the PATH
+    ENV.prepend_path "PATH", Formula["python"].opt_bin
+    ENV.prepend_path "PATH", Formula["python"].opt_libexec/"bin"
+
+    if system_python?
+      ENV["PYTHONPATH"] = "#{HOMEBREW_PREFIX}/lib/python#{short_version}/site-packages"
+    end
+  end
+
+  private
+
+  def short_version
+    @short_version ||= Language::Python.major_minor_version which_python
+  end
+
+  def which_python
+    python = which python_binary
+    return unless python
+    Pathname.new Utils.popen_read(python, "-c", "import sys; print(sys.executable)").strip
+  end
+
+  def system_python
+    "/usr/bin/#{python_binary}"
+  end
+
+  def system_python?
+    system_python == which_python.to_s
+  end
+
+  def python_binary
+    "python2.7"
+  end
+
+  # Deprecated
+  alias to_s python_binary
+end
+
+class Python3Requirement < PythonRequirement
+  fatal true
+  default_formula "python3"
+
+  satisfy(build_env: false) { which_python }
+
+  private
+
+  def python_binary
+    "python3"
+  end
+end