.travis/install.sh: shell script to install pyenv (used to install various Pythons); install virtualenv and tox

.travis/install.sh

@@ -0,0 +1,54 @@
+#!/bin/bash
+
+set -e
+set -x
+
+if [[ "$(uname -s)" == 'Darwin' ]]; then
+    brew update || brew update
+    brew install pyenv
+    brew outdated pyenv || brew upgrade pyenv
+
+    if which -s pyenv; then
+        eval "$(pyenv init -)"
+    fi
+
+    case "${TOXENV}" in
+        py27)
+            curl -O https://bootstrap.pypa.io/get-pip.py
+            python get-pip.py --user
+            ;;
+        py33)
+            pyenv install 3.3.6
+            pyenv global 3.3.6
+            ;;
+        py34)
+            pyenv install 3.4.3
+            pyenv global 3.4.3
+            ;;
+        py35)
+            pyenv install 3.5.0
+            pyenv global 3.5.0
+            ;;
+        pypy)
+            pyenv install pypy-4.0.1
+            pyenv global pypy-4.0.1
+            ;;
+    esac
+    pyenv rehash
+    python -m pip install --user virtualenv
+else
+    # install pyenv to get latest pypy
+    if [[ "${TOXENV}" == "pypy" ]]; then
+        git clone https://github.com/yyuu/pyenv.git ~/.pyenv
+        PYENV_ROOT="$HOME/.pyenv"
+        PATH="$PYENV_ROOT/bin:$PATH"
+        eval "$(pyenv init -)"
+        pyenv install pypy-4.0.1
+        pyenv global pypy-4.0.1
+    fi
+    pip install virtualenv
+fi
+
+python -m virtualenv ~/.venv
+source ~/.venv/bin/activate
+pip install tox