Merge pull request #894 from heroku/undo-revert

Reapply pipenv-ci bugfix

.github/workflows/check_changelog.yml

@@ -0,0 +1,12 @@
+name: Check Changelog
+
+on: [pull_request]
+
+jobs:
+ build:
+   runs-on: ubuntu-latest
+   steps:
+   - uses: actions/checkout@v1
+   - name: Check that CHANGELOG is touched
+     run: |
+       cat $GITHUB_EVENT_PATH | jq .pull_request.title |  grep -i '\[\(\(changelog skip\)\|\(ci skip\)\)\]' ||  git diff remotes/origin/${{ github.base_ref }} --name-only | grep CHANGELOG.md

.gitignore

@@ -7,3 +7,6 @@ repos/*
 
 #Venv
 buildpack/*
+
+builds/dockerenv.staging*
+builds/dockerenv.production

.pre-commit-config.yaml

@@ -0,0 +1,7 @@
+repos:
+-   repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v2.3.0
+    hooks:
+    -   id: check-yaml
+    -   id: end-of-file-fixer
+    -   id: trailing-whitespace

.travis.yml

@@ -1,39 +1,39 @@
 language: ruby
 dist: trusty
 sudo: required
+
 rvm:
 - 2.4.4
 before_script:
   - gem install bundler -v 1.16.2
-  - bundle exec rake hatchet:setup_travis
-before_install:
-  - sudo bash etc/ci-setup.sh
+  - bundle exec hatchet ci:setup
+
+script:
+  - docker build --pull --tag travis-build-cedar-14 --file $(pwd)/builds/cedar-14.Dockerfile .
+  - docker run --rm -e "STACK=cedar-14" travis-build-cedar-14 bash $TESTFOLDER
+  - docker build --pull --tag travis-build-heroku-16 --file $(pwd)/builds/heroku-16.Dockerfile .
+  - docker run --rm -e "STACK=heroku-16" travis-build-heroku-16 bash $TESTFOLDER
+  - docker build --pull --tag travis-build-heroku-18 --file $(pwd)/builds/heroku-18.Dockerfile .
+  - docker run --rm -e "STACK=heroku-18" travis-build-heroku-18 bash $TESTFOLDER
+
 jobs:
   include:
   - stage: Bash linting (shellcheck)
     sudo: false
-    before_install:
-    - wget -c https://goo.gl/ZzKHFv -O - | tar -xvJ -C /tmp/
-    - PATH="/tmp/shellcheck-latest:$PATH"
     script: make check
-  - stage: Stack Unit Tests
-    services: docker
-    env: STACK=heroku-18
-    script: "./tests.sh"
-  - stage: Stack Unit Tests
-    services: docker
-    env: STACK=heroku-16
-    script: "./tests.sh"
-  - stage: Stack Unit Tests
-    services: docker
-    env: STACK=cedar-14
-    script: "./tests.sh"
   - stage: Hatchet Integration
+    if: branch = master
+    name: Run Hatchet
     script: "bundle exec rspec"
 env:
+  matrix:
+    - TESTFOLDER=test/run-deps
+    - TESTFOLDER=test/run-versions
+    - TESTFOLDER=test/run-features
   global:
-  - HATCHET_RETRIES=3
-  - IS_RUNNING_ON_CI=true
-  - HATCHET_APP_LIMIT=5
-  - secure: yjtlPE5FbVxTKnjUy/tZUBgSEf4qADD3QOxtgziuid73S0U/1IEXlMGFULsQzIjtlHKmHeywZqpVVEpthIH4RuT7uoX1Pb7SSM/g0T8fT3VoEFbFK1uYl0oZQbUS4Klxv9tPiumj8if3m6ULEGIz1X0wZcMOC0tMLwVCnwmap0E=
-  - secure: ZeFTHWwnpIKE9nAqs88ocmiQh7bKce84lilGm5J23nf3N6V4wNyLwqlkvsM008WGBCaOg9AUx7ZunasT0ANsR5gLP3eV2UUg7ILdRgV2Gy13eNRFheC4PHdN92RqQ3aKoqlIv2K999xlhVjod0NzhkQQXB6PddfQINbuU7ks6As=
+    - HATCHET_RETRIES=3
+    - IS_RUNNING_ON_CI=true
+    - HATCHET_APP_LIMIT=5
+    - HATCHET_DEPLOY_STRATEGY=git
+    - secure: yjtlPE5FbVxTKnjUy/tZUBgSEf4qADD3QOxtgziuid73S0U/1IEXlMGFULsQzIjtlHKmHeywZqpVVEpthIH4RuT7uoX1Pb7SSM/g0T8fT3VoEFbFK1uYl0oZQbUS4Klxv9tPiumj8if3m6ULEGIz1X0wZcMOC0tMLwVCnwmap0E=
+    - secure: ZeFTHWwnpIKE9nAqs88ocmiQh7bKce84lilGm5J23nf3N6V4wNyLwqlkvsM008WGBCaOg9AUx7ZunasT0ANsR5gLP3eV2UUg7ILdRgV2Gy13eNRFheC4PHdN92RqQ3aKoqlIv2K999xlhVjod0NzhkQQXB6PddfQINbuU7ks6As=

CHANGELOG.md

@@ -1,14 +1,97 @@
 # Python Buildpack Changelog
 
-# 140 (2018-10-09)
+# Master
+
+- Bugfix: Pipenv no longer installs twice in CI
+
+--------------------------------------------------------------------------------
+
+# 159 (2019-10-22)
+
+- Python 2.7.17 now available on Heroku 18 and 16.
+
+# 158 (2019-10-21)
+
+- Python 3.7.5 and 3.8.0 now available on Heroku 18 and 16.
+- Add support for Python 3.8 branch
+- Sqlite3 Update:
+  - Test Improvements
+- Add support for staging binary testing
+
+# 157 (2019-09-18)
+
+- Typo fixes
+
+# 156 (2019-09-12)
+
+- Python 3.6.9 and 3.7.4 now available.
+
+- Move get-pip utility to S3
+- Build utility and documentation updates
+- Bump Hatchet tests to point at new default python version.
+
+# 155 (2019-08-22)
+
+add docs and make target for heroku-18 bob builds
+
+# 154 (2019-07-17)
+
+Fix python 3.5.7 formula actually building 3.7.2
+
+# 153 (2019-06-21)
+
+Hotfix for broken heroku-16 deploys
+
+# 152 (2019-04-04)
+
+Python 3.7.3 now available.
+
+# 151 (2019-03-21)
+
+Python 3.5.7 and 3.4.10 now available on all Heroku stacks.
+
+# 150 (2019-03-13)
+
+Python 2.7.16 now available on all Heroku stacks.
+
+# 149 (2019-03-04)
+
+Hotfix for broken Cedar 14 deploys
+
+# 148 (2019-02-21)
+
+No user facing changes, improving internal metrics
+
+# 147 (2019-02-07)
+
+Python 3.7.2 and 3.6.8 now available on all Heroku stacks.
+
+# 146 (2018-11-11)
+
+Python 3.7.1, 3.6.7, 3.5.6 and 3.4.9 now available on all Heroku stacks.
+
+# 145 (2018-11-08)
+
+Testing and tooling expanded to better support new runtimes
+
+# 144 (2018-10-10)
+
+Switch to cautious upgrade for Pipenv install to ensure the pinned pip version
+is used with Pipenv
+
+# 143 (2018-10-09)
 
 Add support for detecting SLUGIFY_USES_TEXT_UNIDECODE, which is required to
 install Apache Airflow version 1.10 or higher.
 
-# 139 (2018-10-08)
+# 142 (2018-10-08)
 
 Improvements to Python install messaging
 
+# 139, 140, 141
+
+No user-facing changes, documenting for version clarity
+
 # 138 (2018-08-01)
 
 Use stack image SQLite3 instead of vendoring

Gemfile.lock

@@ -6,16 +6,16 @@ GEM
       i18n (>= 0.7, < 2)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
-    concurrent-ruby (1.0.5)
+    concurrent-ruby (1.1.3)
     diff-lcs (1.3)
     erubis (2.7.0)
     excon (0.62.0)
-    heroics (0.0.24)
+    heroics (0.0.25)
       erubis (~> 2.0)
       excon
       moneta
       multi_json (>= 1.9.2)
-    heroku_hatchet (4.0.2)
+    heroku_hatchet (4.0.6)
       excon (~> 0)
       minitest-retry (~> 0.1.9)
       platform-api (~> 2)
@@ -23,16 +23,16 @@ GEM
       rrrretry (~> 1)
       thor (~> 0)
       threaded (~> 0)
-    i18n (1.1.0)
+    i18n (1.1.1)
       concurrent-ruby (~> 1.0)
     minitest (5.11.3)
     minitest-retry (0.1.9)
       minitest (>= 5.0)
-    moneta (0.8.1)
+    moneta (1.0.0)
     multi_json (1.13.1)
-    platform-api (2.1.0)
-      heroics (~> 0.0.23)
-      moneta (~> 0.8.1)
+    platform-api (2.2.0)
+      heroics (~> 0.0.25)
+      moneta (~> 1.0.0)
     rake (12.3.1)
     repl_runner (0.0.3)
       activesupport
@@ -52,7 +52,7 @@ GEM
     rspec-retry (0.6.1)
       rspec-core (> 3.3)
     rspec-support (3.8.0)
-    thor (0.20.0)
+    thor (0.20.3)
     thread_safe (0.3.6)
     threaded (0.0.4)
     tzinfo (1.2.5)

Makefile

@@ -1,32 +1,32 @@
 # These targets are not files
 .PHONY: tests
 
-test: test-heroku-16
+test: test-heroku-18 test-heroku-16 test-cedar-14
 
 check:
-	@shellcheck -x bin/compile bin/detect bin/release bin/test-compile bin/utils bin/warnings
+	@shellcheck -x bin/compile bin/detect bin/release bin/test-compile bin/utils bin/warnings bin/default_pythons
 	@shellcheck -x bin/steps/collectstatic bin/steps/eggpath-fix  bin/steps/eggpath-fix2 bin/steps/gdal bin/steps/geo-libs bin/steps/mercurial bin/steps/nltk bin/steps/pip-install bin/steps/pip-uninstall bin/steps/pipenv bin/steps/pipenv-python-version bin/steps/pylibmc bin/steps/python
 	@shellcheck -x bin/steps/hooks/*
 
 test-cedar-14:
 	@echo "Running tests in docker (cedar-14)..."
-	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=cedar-14" heroku/cedar:14 bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run;'
+	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=cedar-14" heroku/cedar:14 bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run-deps; test/run-features; test/run-versions;'
 	@echo ""
 
 test-heroku-16:
 	@echo "Running tests in docker (heroku-16)..."
-	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-16" heroku/heroku:16-build bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run;'
+	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-16" heroku/heroku:16-build bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run-deps; test/run-features; test/run-versions;'
 	@echo ""
 
 test-heroku-18:
 	@echo "Running tests in docker (heroku-18)..."
-	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-18" heroku/heroku:18-build bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run;'
+	@docker run -v $(shell pwd):/buildpack:ro --rm -it -e "STACK=heroku-18" heroku/heroku:18-build bash -c 'cp -r /buildpack /buildpack_test; cd /buildpack_test/; test/run-deps; test/run-features; test/run-versions;'
 	@echo ""
 
 buildenv-heroku-16:
 	@echo "Creating build environment (heroku-16)..."
 	@echo
-	@docker build --pull -t python-buildenv-heroku-16 .
+	@docker build --pull -f $(shell pwd)/builds/heroku-16.Dockerfile -t python-buildenv-heroku-16 .
 	@echo
 	@echo "Usage..."
 	@echo
@@ -36,6 +36,19 @@ buildenv-heroku-16:
 	@echo
 	@docker run -it --rm python-buildenv-heroku-16
 
+buildenv-heroku-18:
+	@echo "Creating build environment (heroku-18)..."
+	@echo
+	@docker build --pull -f $(shell pwd)/builds/heroku-18.Dockerfile -t python-buildenv-heroku-18 .
+	@echo
+	@echo "Usage..."
+	@echo
+	@echo "  $$ export AWS_ACCESS_KEY_ID=foo AWS_SECRET_ACCESS_KEY=bar  # Optional unless deploying"
+	@echo "  $$ bob build runtimes/python-2.7.13"
+	@echo "  $$ bob deploy runtimes/python-2.7.13"
+	@echo
+	@docker run -it --rm python-buildenv-heroku-18
+
 tools:
 	git clone https://github.com/kennethreitz/pip-pop.git
 	mv pip-pop/bin/* vendor/pip-pop/

README.md

@@ -4,36 +4,54 @@
 
 [![Build Status](https://travis-ci.org/heroku/heroku-buildpack-python.svg?branch=master)](https://travis-ci.org/heroku/heroku-buildpack-python)
 
-This is the official [Heroku buildpack](https://devcenter.heroku.com/articles/buildpacks) for Python apps, powered by [Pipenv](http://docs.pipenv.org/), [pip](https://pip.pypa.io/) and other excellent software.
+This is the official [Heroku buildpack](https://devcenter.heroku.com/articles/buildpacks) for Python apps.
 
-Recommended web frameworks include **Django** and **Flask**. The recommended webserver is **Gunicorn**. There are no restrictions around what software can be used (as long as it's pip-installable). Web processes must bind to `$PORT`, and only the HTTP protocol is permitted for incoming connections.
+Recommended web frameworks include **Django** and **Flask**, among others. The recommended webserver is **Gunicorn**. There are no restrictions around what software can be used (as long as it's pip-installable). Web processes must bind to `$PORT`, and only the HTTP protocol is permitted for incoming connections.
 
-Python packages with C dependencies that are not [available on the stack image](https://devcenter.heroku.com/articles/stack-packages) are generally not supported, unless `manylinux` wheels are provided by the package maintainers (common). For recommended solutions, check out [this article](https://devcenter.heroku.com/articles/python-c-deps) for more information. 
+Python packages with C dependencies that are not [available on the stack image](https://devcenter.heroku.com/articles/stack-packages) are generally not supported, unless `manylinux` wheels are provided by the package maintainers (common). For recommended solutions, check out [this article](https://devcenter.heroku.com/articles/python-c-deps) for more information.
 
 See it in Action
 ----------------
+```
+$ ls
+my-application		requirements.txt	runtime.txt
 
-Deploying a Python application couldn't be easier:
+$ git push heroku master
+Counting objects: 4, done.
+Delta compression using up to 8 threads.
+Compressing objects: 100% (2/2), done.
+Writing objects: 100% (4/4), 276 bytes | 276.00 KiB/s, done.
+Total 4 (delta 0), reused 0 (delta 0)
+remote: Compressing source files... done.
+remote: Building source:
+remote:
+remote: -----> Python app detected
+remote: -----> Installing python-3.7.4
+remote: -----> Installing pip
+remote: -----> Installing SQLite3
+remote: -----> Installing requirements with pip
+remote:        Collecting flask (from -r /tmp/build_c2c067ef79ff14c9bf1aed6796f9ed1f/requirements.txt (line 1))
+remote:          Downloading ...
+remote:        Installing collected packages: Werkzeug, click, MarkupSafe, Jinja2, itsdangerous, flask
+remote:        Successfully installed Jinja2-2.10 MarkupSafe-1.1.0 Werkzeug-0.14.1 click-7.0 flask-1.0.2 itsdangerous-1.1.0
+remote:
+remote: -----> Discovering process types
+remote:        Procfile declares types -> (none)
+remote:
+```
 
-    $ ls
-    Pipfile		Pipfile.lock	Procfile	web.py
+A `requirements.txt` must be present at the root of your application's repository to deploy.
 
-    $ heroku create --buildpack heroku/python
+To specify your python version, you also need a `runtime.txt` file - unless you are using the default Python runtime version.
 
-    $ git push heroku master
-    …
-    -----> Python app detected
-    -----> Installing python-3.6.6
-    -----> Installing pip
-    -----> Installing requirements with Pipenv 2018.5.18…
-           ...
-           Installing dependencies from Pipfile…
-    -----> Discovering process types
-           Procfile declares types -> (none)
+Current default Python Runtime: Python 3.6.9
 
-A `Pipfile` or `requirements.txt` must be present at the root of your application's repository.
+Alternatively, you can provide a `setup.py` file, or a `Pipfile`. Using `Pipenv` will generate `runtime.txt` based on `python-version` at build time.
 
-You can also specify the latest production release of this buildpack for upcoming builds of an existing application:
+Specify a Buildpack Version
+---------------------------
+
+You can specify the latest production release of this buildpack for upcoming builds of an existing application:
 
     $ heroku buildpacks:set heroku/python
 
@@ -41,23 +59,30 @@ You can also specify the latest production release of this buildpack for upcomin
 Specify a Python Runtime
 ------------------------
 
-Specific versions of the Python runtime can be specified in your `Pipfile`:
+Supported runtime options include:
 
-    [requires]
-    python_version = "2.7"
+- `python-3.7.4`
+- `python-3.6.9`
+- `python-2.7.17`
 
-Or, more specifically:
+## Tests
 
-    [requires]
-    python_full_version = "2.7.15"
+The buildpack tests use [Docker](https://www.docker.com/) to simulate
+Heroku's [stack images.](https://devcenter.heroku.com/articles/stack)
 
-Or, with a `runtime.txt` file:
+To run the test suite:
 
-    $ cat runtime.txt
-    python-2.7.15
+```
+make test
+```
 
-Runtime options include:
+Or to test in a particular stack:
 
-- `python-3.7.0`
-- `python-3.6.6`
-- `python-2.7.15`
+```
+make test-heroku-18
+make test-heroku-16
+```
+
+The tests are run via the vendored
+[shunit2](https://github.com/kward/shunit2)
+test framework.

bin/compile

@@ -42,24 +42,30 @@ export BUILD_DIR CACHE_DIR ENV_DIR
 VENDOR_URL="https://lang-python.s3.amazonaws.com/$STACK"
 if [[ -n ${BUILDPACK_VENDOR_URL:-} ]]; then
     VENDOR_URL="$BUILDPACK_VENDOR_URL"
+elif [[ -n ${USE_STAGING_BINARIES} ]]; then
+    VENDOR_URL="$USE_STAGING_BINARIES/$STACK"
 fi
 export VENDOR_URL
 
-# Which versions of Python are we using?
-# These variables are used to specify which versions of Python to install by default,
-# as well as prompt the user to upgrade if they are using an un–supported version.
-# Note: When 3.7 lands, I recommend switching to LATEST_36 and LATEST_37.
-DEFAULT_PYTHON_VERSION="python-3.6.6"
-LATEST_36="python-3.6.6"
-LATEST_37="python-3.7.0"
-LATEST_2="python-2.7.15"
+# Default Python Versions
+# shellcheck source=bin/default_pythons
+source "$BIN_DIR/default_pythons"
+
+# Supported Python Branches
+PY38="python-3.8"
+PY37="python-3.7"
+PY36="python-3.6"
+PY35="python-3.5"
+PY34="python-3.4"
+PY27="python-2.7"
 
 # Which stack is used (for binary downloading), if none is provided (e.g. outside of Heroku)?
 DEFAULT_PYTHON_STACK="cedar-14"
 # If pip doesn't match this version (the version we install), run the installer.
 PIP_UPDATE="9.0.2"
 
-export DEFAULT_PYTHON_VERSION DEFAULT_PYTHON_STACK PIP_UPDATE LATEST_2 LATEST_36 LATEST_37
+export DEFAULT_PYTHON_STACK PIP_UPDATE
+export PY37 PY36 PY35 PY27 PY34
 
 # Common Problem Warnings:
 # This section creates a temporary file in which to stick the output of `pip install`.

bin/default_pythons

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+DEFAULT_PYTHON_VERSION="python-3.6.9"
+LATEST_38="python-3.8.0"
+LATEST_37="python-3.7.5"
+LATEST_36="python-3.6.9"
+LATEST_35="python-3.5.7"
+LATEST_34="python-3.4.10"
+LATEST_27="python-2.7.17"
+
+export DEFAULT_PYTHON_VERSION LATEST_38 LATEST_37 LATEST_36 LATEST_35 LATEST_34 LATEST_27

bin/steps/gdal

@@ -26,9 +26,9 @@ if (pip-grep -s requirements.txt GDAL gdal pygdal &> /dev/null) then
     mkdir -p .heroku/vendor
     # Download and extract cryptography into target vendor directory.
     curl "$VENDORED_GDAL" -s | tar zxv -C .heroku/vendor &> /dev/null
+    mcount "steps.vendor.gdal"
   fi
 
   GDAL=$(pwd)/vendor
   export GDAL
 fi
-

bin/steps/geo-libs

@@ -22,6 +22,7 @@ source "$BIN_DIR/utils"
 
 # If GDAL exists within requirements, use vendored gdal.
 if [[ "$BUILD_WITH_GEO_LIBRARIES" ]]; then
+  mcount "buildvar.BUILD_WITH_GEO_LIBRARIES"
 
   if [ ! -f ".heroku/vendor/bin/proj" ]; then
     echo "-----> Bootstrapping gdal, geos, proj."
@@ -31,9 +32,11 @@ if [[ "$BUILD_WITH_GEO_LIBRARIES" ]]; then
     curl "$VENDORED_GEOS" -s | tar zxv -C .heroku/vendor &> /dev/null
     curl "$VENDORED_PROJ" -s | tar zxv -C .heroku/vendor &> /dev/null
 
+    mcount "steps.vendor.geo_libs"
     # Copy libjasper from build image to slug.
     if [[ "$STACK" == "heroku-16" ]]; then
       cp /usr/lib/x86_64-linux-gnu/libjasper.so* ".heroku/vendor/lib/."
+      mcount "steps.vendor.libjasper"
     fi
 
   fi

bin/steps/mercurial

@@ -4,6 +4,6 @@
 if [[ -f "requirements.txt" ]]; then
 	if (grep -Fiq "hg+" requirements.txt) then
 		/app/.heroku/python/bin/pip install  mercurial | cleanup | indent
+		mcount "steps.mercurial"
 	fi
 fi
-

bin/steps/nltk

@@ -27,6 +27,8 @@ if sp-grep -s nltk; then
         python -m nltk.downloader -d "$BUILD_DIR/.heroku/python/nltk_data" "${nltk_packages[@]}" | indent
         set_env NLTK_DATA "/app/.heroku/python/nltk_data"
 
+        mcount "buildvar.NLTK_PACKAGES_DEFINITION"
+        mcount "steps.nltk"
     else
         puts-warn "'nltk.txt' not found, not downloading any corpora"
         puts-warn "Learn more: https://devcenter.heroku.com/articles/python-nltk"

bin/steps/pip-install

@@ -13,7 +13,7 @@ if [ ! "$SKIP_PIP_INSTALL" ]; then
     # and makes them accessible to the pip install process.
     #
     # PIP_EXTRA_INDEX_URL allows for an alternate pypi URL to be used.
-    if [[ -r $ENV_DIR/PIP_EXTRA_INDEX_URL ]]; then
+    if [[ -r "$ENV_DIR/PIP_EXTRA_INDEX_URL" ]]; then
         PIP_EXTRA_INDEX_URL="$(cat "$ENV_DIR/PIP_EXTRA_INDEX_URL")"
         export PIP_EXTRA_INDEX_URL
         mcount "buildvar.PIP_EXTRA_INDEX_URL"
@@ -22,7 +22,7 @@ if [ ! "$SKIP_PIP_INSTALL" ]; then
     set +e
 
     # Set SLUGIFY_USES_TEXT_UNIDECODE, required for Airflow versions >=1.10
-    if [[ -r $ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE ]]; then
+    if [[ -r "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE" ]]; then
         SLUGIFY_USES_TEXT_UNIDECODE="$(cat "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE")"
         export SLUGIFY_USES_TEXT_UNIDECODE
         mcount "buildvar.SLUGIFY_USES_TEXT_UNIDECODE"
@@ -38,7 +38,9 @@ if [ ! "$SKIP_PIP_INSTALL" ]; then
         mcount "failure.none-version"
     fi
 
-
+    if [ ! -f "$BUILD_DIR/.heroku/python/bin/pip" ]; then
+        exit 1
+    fi
     /app/.heroku/python/bin/pip install -r "$BUILD_DIR/requirements.txt" --exists-action=w --src=/app/.heroku/src --disable-pip-version-check --no-cache-dir 2>&1 | tee "$WARNINGS_LOG" | cleanup | indent
     PIP_STATUS="${PIPESTATUS[0]}"
     set -e

bin/steps/pip-uninstall

@@ -13,7 +13,7 @@ if [ ! "$SKIP_PIP_INSTALL" ]; then
 
 
     if ! pip-diff --stale requirements-declared.txt requirements.txt --exclude setuptools pip wheel > .heroku/python/requirements-stale.txt; then
-      mount "failure.bad-requirements"
+      mcount "failure.bad-requirements"
     fi
 
     rm -fr requirements-declared.txt

bin/steps/pipenv

@@ -20,14 +20,13 @@ if [[ -f Pipfile.lock ]]; then
                 export SKIP_PIPENV_INSTALL=1
                 export SKIP_PIP_INSTALL=1
             fi
-
         fi
     fi
 fi
 
 
 if [ ! "$SKIP_PIPENV_INSTALL" ]; then
-    # Pipenv support (Generate requriements.txt with pipenv).
+    # Pipenv support (Generate requirements.txt with pipenv).
     if [[ -f Pipfile ]]; then
         # Measure that we're using Pipenv.
         mcount "tool.pipenv"
@@ -40,14 +39,14 @@ if [ ! "$SKIP_PIPENV_INSTALL" ]; then
         # and makes them accessible to the pip install process.
         #
         # PIP_EXTRA_INDEX_URL allows for an alternate pypi URL to be used.
-        if [[ -r $ENV_DIR/PIP_EXTRA_INDEX_URL ]]; then
+        if [[ -r "$ENV_DIR/PIP_EXTRA_INDEX_URL" ]]; then
             PIP_EXTRA_INDEX_URL="$(cat "$ENV_DIR/PIP_EXTRA_INDEX_URL")"
             export PIP_EXTRA_INDEX_URL
             mcount "buildvar.PIP_EXTRA_INDEX_URL"
         fi
 
         # Set SLUGIFY_USES_TEXT_UNIDECODE, required for Airflow versions >=1.10
-        if [[ -r $ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE ]]; then
+        if [[ -r "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE" ]]; then
             SLUGIFY_USES_TEXT_UNIDECODE="$(cat "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE")"
             export SLUGIFY_USES_TEXT_UNIDECODE
             mcount "buildvar.SLUGIFY_USES_TEXT_UNIDECODE"
@@ -56,12 +55,21 @@ if [ ! "$SKIP_PIPENV_INSTALL" ]; then
         export PIPENV_VERSION="2018.5.18"
 
         # Install pipenv.
-        /app/.heroku/python/bin/pip install pipenv==$PIPENV_VERSION --upgrade &> /dev/null
+        # Due to weird old pip behavior and pipenv behavior, pipenv upgrades pip
+        # to latest if only --upgrade is specified. Specify upgrade strategy to
+        # avoid this eager behavior.
+        /app/.heroku/python/bin/pip install pipenv==$PIPENV_VERSION --upgrade --upgrade-strategy only-if-needed &> /dev/null
+
+        # Install the test dependencies, for CI.
+        if [ "$INSTALL_TEST" ]; then
+            puts-step "Installing test dependencies…"
+            /app/.heroku/python/bin/pipenv install --dev --system --deploy 2>&1 | cleanup | indent
 
         # Install the dependencies.
-        if [[ ! -f Pipfile.lock ]]; then
+        elif [[ ! -f Pipfile.lock ]]; then
             puts-step "Installing dependencies with Pipenv $PIPENV_VERSION…"
             /app/.heroku/python/bin/pipenv install --system --skip-lock 2>&1 | indent
+
         else
             pipenv-to-pip Pipfile.lock > requirements.txt
             "$BIN_DIR/steps/pip-uninstall"
@@ -71,12 +79,6 @@ if [ ! "$SKIP_PIPENV_INSTALL" ]; then
             puts-step "Installing dependencies with Pipenv $PIPENV_VERSION…"
             /app/.heroku/python/bin/pipenv install --system --deploy 2>&1 | indent
         fi
-
-        # Install the test dependencies, for CI.
-        if [ "$INSTALL_TEST" ]; then
-            puts-step "Installing test dependencies…"
-            /app/.heroku/python/bin/pipenv install --dev --system --deploy 2>&1 | cleanup | indent
-        fi
     fi
 else
     export SKIP_PIP_INSTALL=1

bin/steps/pipenv-python-version

@@ -19,7 +19,7 @@ if [[ -f $BUILD_DIR/Pipfile ]]; then
             if [[ "$PYTHON" == "null" ]]; then
                 PYTHON=$(jq -r '._meta.requires.python_version' "$BUILD_DIR/Pipfile.lock")
                 if [ "$PYTHON" = 2.7 ]; then
-                    echo "$LATEST_2" > "$BUILD_DIR/runtime.txt"
+                    echo "$LATEST_27" > "$BUILD_DIR/runtime.txt"
                 fi
                 if [ "$PYTHON" = 3.6 ]; then
                     echo "$LATEST_36" > "$BUILD_DIR/runtime.txt"
@@ -33,4 +33,3 @@ if [[ -f $BUILD_DIR/Pipfile ]]; then
         fi
     fi
 fi
-

bin/steps/pylibmc

@@ -29,6 +29,7 @@ if (pip-grep -s requirements.txt pylibmc &> /dev/null) then
     mkdir -p .heroku/vendor
     # Download and extract libmemcached into target vendor directory.
     curl "$VENDORED_MEMCACHED" -s | tar zxv -C .heroku/vendor &> /dev/null
+    mcount "steps.vendor.pylibmc"
   fi
 
   LIBMEMCACHED=$(pwd)/vendor

bin/steps/python

@@ -7,41 +7,56 @@ PYTHON_VERSION=$(cat runtime.txt)
 # The location of the pre-compiled python binary.
 VENDORED_PYTHON="${VENDOR_URL}/runtimes/$PYTHON_VERSION.tar.gz"
 
-if [[ $PYTHON_VERSION =~ ^python-2 ]]; then
-  if [[ "$PYTHON_VERSION" != "$LATEST_2" ]]; then
-    puts-warn "The latest version of Python 2 is $LATEST_2 (you are using $PYTHON_VERSION, which is unsupported)."
-    puts-warn "We recommend upgrading by specifying the latest version ($LATEST_2)."
-    echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
-  else
-    echo "       Using supported version of Python 2 ($PYTHON_VERSION)"
-  fi
-else
-  if [[ $PYTHON_VERSION =~ ^python-3 ]]; then
-    if [[ $PYTHON_VERSION =~ ^python-3.7 ]]; then
-      if [[ "$PYTHON_VERSION" != "$LATEST_37" ]]; then
-      puts-warn "The latest version of Python 3.7 is $LATEST_37 (you are using $PYTHON_VERSION, which is unsupported)."
-      puts-warn "We recommend upgrading by specifying the latest version ($LATEST_37)."
+SECURITY_UPDATE="Python has released a security update! Please consider upgrading to"
+
+# check if runtime exists
+if curl --output /dev/null --silent --head --fail "$VENDORED_PYTHON"; then
+  if [[ "$PYTHON_VERSION" == $PY38* ]]; then
+    # do things to alert the user of security release available
+    if [ "$PYTHON_VERSION" != "$LATEST_38" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_38"
       echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
-      else
-        echo "       Using supported version of Python 3.7 ($PYTHON_VERSION)"
-      fi
-    else
-      if [[ $PYTHON_VERSION =~ ^python-3.6 ]]; then
-        if [[ "$PYTHON_VERSION" != "$LATEST_36" ]]; then
-          puts-warn "The latest version of Python 3.6 is $LATEST_36 (you are using $PYTHON_VERSION, which is unsupported)."
-          puts-warn "We recommend upgrading by specifying the latest version ($LATEST_36)."
-          echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
-        else
-          echo "       Using supported version of Python 3.6 ($PYTHON_VERSION)"
-        fi
-      else
-        puts-warn "Heroku supports runtime versions $LATEST_37, $LATEST_36 and $LATEST_2." 
-        puts-warn "You are using $PYTHON_VERSION, which is unsupported."
-        puts-warn "We recommend upgrading by specifying the default supported version ($LATEST_36)."
-        echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
-      fi
     fi
   fi
+  if [[ "$PYTHON_VERSION" == $PY37* ]]; then
+    # do things to alert the user of security release available
+    if [ "$PYTHON_VERSION" != "$LATEST_37" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_37"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+  if [[ "$PYTHON_VERSION" == $PY36* ]]; then
+    # security update note
+    if [ "$PYTHON_VERSION" != "$LATEST_36" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_36"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+  if [[ "$PYTHON_VERSION" == $PY35* ]]; then
+    # security update note
+    if [ "$PYTHON_VERSION" != "$LATEST_35" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_35"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+  if [[ "$PYTHON_VERSION" == $PY34* ]]; then
+    # security update note
+    if [ "$PYTHON_VERSION" != "$LATEST_34" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_34"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+  if [[ "$PYTHON_VERSION" == $PY27* ]]; then
+    # security update note
+    if [ "$PYTHON_VERSION" != "$LATEST_27" ]; then
+      puts-warn "$SECURITY_UPDATE" "$LATEST_27"
+      echo "       Learn More: https://devcenter.heroku.com/articles/python-runtimes"
+    fi
+  fi
+else
+  puts-warn "Requested runtime ($PYTHON_VERSION) is not available for this stack ($STACK)."
+  puts-warn "Aborting.  More info: https://devcenter.heroku.com/articles/python-support"
+  exit 1
 fi
 
 if [[ "$STACK" != "$CACHED_PYTHON_STACK" ]]; then
@@ -89,6 +104,15 @@ if [ ! "$SKIP_INSTALL" ]; then
   hash -r
 fi
 
+# Heroku uses the get-pip utility maintained by the Python community to vendor Pip.
+# https://github.com/pypa/get-pip
+GETPIP="https://lang-python.s3.amazonaws.com/etc/get-pip.py"
+
+if ! curl -s "${GETPIP}" -o "$ROOT_DIR/get-pip.py" &> /dev/null; then
+    mcount "failure.python.get-pip"
+    echo "Failed to pull down get-pip"
+    exit 1
+fi
 
 # If Pip isn't up to date:
 if [ "$FRESH_PYTHON" ] || [[ ! $(pip --version) == *$PIP_UPDATE* ]]; then
@@ -99,9 +123,8 @@ if [ "$FRESH_PYTHON" ] || [[ ! $(pip --version) == *$PIP_UPDATE* ]]; then
   rm -fr /app/.heroku/python/lib/python*/site-packages/pip-*
   rm -fr /app/.heroku/python/lib/python*/site-packages/setuptools-*
 
-  /app/.heroku/python/bin/python "$ROOT_DIR/vendor/get-pip.py" pip=="$PIP_UPDATE" &> /dev/null
+  /app/.heroku/python/bin/python "$ROOT_DIR/get-pip.py" pip=="$PIP_UPDATE" &> /dev/null
   /app/.heroku/python/bin/pip install "$ROOT_DIR/vendor/setuptools-39.0.1-py2.py3-none-any.whl" &> /dev/null
-
 fi
 
 set -e

bin/steps/sqlite3

@@ -4,7 +4,13 @@
 source "$BIN_DIR/utils"
 
 sqlite3_version() {
-  SQLITE3_VERSION=${SQLITE3_VERSION:-$(dpkg -s libsqlite3-0 | grep Version | sed 's/Version: //')}
+  if [ "$STACK" = "cedar-14" ]; then
+    SQLITE3_VERSION="3.8.2-1ubuntu2.2"
+  elif [ "$STACK" = "heroku-16" ]; then
+    SQLITE3_VERSION="3.11.0-1ubuntu1.2"
+  else
+    SQLITE3_VERSION=${SQLITE3_VERSION:-$(dpkg -s libsqlite3-0 | grep Version | sed 's/Version: //')}
+  fi
 
   export SQLITE3_VERSION
 }

bin/utils

@@ -89,10 +89,9 @@ python3_check() {
 # Check if Python version needs to install SQLite3
 python_sqlite3_check() {
   VERSION="$1"
-  MIN_PYTHON_3="python-3.6.6"
+  MIN_PYTHON_3="python-3.5.6"
   MIN_PYTHON_2="python-2.7.15"
 
   ( python2_check "$VERSION" && version_gte "$VERSION" "$MIN_PYTHON_2" ) \
-    || ( python3_check "$VERSION" && version_gte "$VERSION" "$MIN_PYTHON_3" ) \
-    || ( version_gte "$VERSION" "3.7.0" )
+    || ( python3_check "$VERSION" && version_gte "$VERSION" "$MIN_PYTHON_3" )
 }

builds/README.md

@@ -1,41 +1,57 @@
 # Python Buildpack Binaries
 
-For Cedar-14 stack
-------------------
+## Building the Docker Images
 
-To get started with it, create an app on Heroku inside a clone of this repository, and set your S3 config vars:
+**After every change to your formulae, perform the following** from the root of the Git repository (not from `builds/`) to rebuild the images for each stack:
 
-    $ heroku create --buildpack https://github.com/heroku/heroku-buildpack-python#not-heroku
-    $ heroku config:set WORKSPACE_DIR=builds
-    $ heroku config:set AWS_ACCESS_KEY_ID=<your_aws_key>
-    $ heroku config:set AWS_SECRET_ACCESS_KEY=<your_aws_secret>
-    $ heroku config:set S3_BUCKET=<your_s3_bucket_name>
+    $ docker build --pull --tag heroku-python-build-cedar-14 --file $(pwd)/builds/cedar-14.Dockerfile .
+    $ docker build --pull --tag heroku-python-build-heroku-16 --file $(pwd)/builds/heroku-16.Dockerfile .
+    $ docker build --pull --tag heroku-python-build-heroku-18 --file $(pwd)/builds/heroku-18.Dockerfile .
 
+## Using the Image
 
-Then, shell into an instance and run a build by giving the name of the formula inside `builds`:
+You can e.g. `bash` into each of the images you built using their tag:
 
-    $ heroku run bash
-    Running `bash` attached to terminal... up, run.6880
-    ~ $ bob build runtimes/python-2.7.6
+    docker run --rm -ti heroku-python-build-cedar-14 bash
+    docker run --rm -ti heroku-python-build-heroku-16 bash
+    docker run --rm -ti heroku-python-build-heroku-18 bash
 
-    Fetching dependencies... found 2:
-      - libraries/sqlite
+You then have a shell where you can run `bob build`, `bob deploy`, and so forth. You can of course also invoke these programs directly with `docker run`:
 
-    Building formula runtimes/python-2.7.6:
-        === Building Python 2.7.6
-        Fetching Python v2.7.6 source...
-        Compiling...
+    docker run --rm -ti heroku-python-build-heroku-18 bob build runtimes/python-2.7.15
 
-If this works, run `bob deploy` instead of `bob build` to have the result uploaded to S3 for you.
+In order to `bob deploy`, AWS credentials must be set up, as well as name and prefix of your custom S3 bucket (unless you're deploying to the Heroku production buckets that are pre-defined in each `Dockerfile`); see next section for details.
 
-To speed things up drastically, it'll usually be a good idea to `heroku run bash --size PX` instead.
+## Configuration
 
-For Heroku-16 stack
--------------------
+File `dockerenv.default` contains a list of required env vars; most of these have default values defined in `Dockerfile`. You can copy this file to a location outside the buildpack and modify it with the values you desire and pass its location with `--env-file`, or pass the env vars to `docker run` using `--env`.
 
-1. Ensure GNU Make and Docker are installed.
-2. From the root of the buildpack repository, run: `make buildenv-heroku-16`
-3. Follow the instructions displayed!
+Out of the box, each `Dockerfile` has the correct values predefined for `S3_BUCKET`, `S3_PREFIX`, and `S3_REGION`. If you're building your own packages, you'll likely want to change `S3_BUCKET` and `S3_PREFIX` to match your info. Instead of setting `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY` into that file, you may also pass them to `docker run` through the environment, or explicitly using `--env`, in order to prevent accidental commits of credentials.
 
+### Passing AWS credentials to the container
 
-Enjoy :)
+If you want to deploy packages and thus need to pass `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY`, you can either pass them explicitly, through your environment, or through an env file.
+
+#### Passing credentials explicitly
+
+    docker run --rm -ti -e AWS_ACCESS_KEY_ID=... -e AWS_SECRET_ACCESS_KEY=... heroku-python-build-heroku-18 bash
+
+#### Passing credentials through  the environment
+
+The two environment variables `AWS_ACCESS_KEY_ID`and `AWS_SECRET_ACCESS_KEY` are defined in `builds/dockerenv.default`, without values. This will cause Docker to "forward" values for these variables from the current environment, so you can pass them in:
+
+    AWS_ACCESS_KEY_ID=... AWS_SECRET_ACCESS_KEY=... docker run --rm -ti --env-file=builds/dockerenv.default heroku-python-build-heroku-18 bash
+
+or
+
+    export AWS_ACCESS_KEY_ID=...
+    export AWS_SECRET_ACCESS_KEY=...
+    docker run --rm -ti --env-file=builds/dockerenv.default heroku-python-build-heroku-18 bash
+
+#### Passing credentials through a separate env file
+
+This method is the easiest for users who want to build packages in their own S3 bucket, as they will have to adjust the `S3_BUCKET` and `S3_PREFIX` environment variable values anyway from their default values.
+
+For this method, it is important to keep the credentials file in a location outside the buildpack, so that your credentials aren't accidentally committed. Copy `builds/dockerenv.default` **to a safe location outside the buildpack directory**, and insert your values for `AWS_ACCESS_KEY_ID`and `AWS_SECRET_ACCESS_KEY`.
+
+    docker run --rm -ti --env-file=../SOMEPATHOUTSIDE/s3.env heroku-python-build-heroku-18 bash

builds/cedar-14.Dockerfile

@@ -1,13 +1,15 @@
-FROM heroku/heroku:18-build
+FROM heroku/cedar:14
 
 WORKDIR /app
 ENV WORKSPACE_DIR="/app/builds" \
     S3_BUCKET="lang-python" \
-    S3_PREFIX="heroku-18/"
+    S3_PREFIX="cedar-14/" \
+    DEBIAN_FRONTEND=noninteractive \
+    STACK="cedar-14"
 
 RUN apt-get update && apt-get install -y python-pip && rm -rf /var/lib/apt/lists/*
 
 COPY requirements.txt /app/
-RUN pip install --disable-pip-version-check --no-cache-dir -r /app/requirements.txt
+RUN pip install -r /app/requirements.txt
 
 COPY . /app

builds/dockerenv.default

@@ -0,0 +1,5 @@
+AWS_ACCESS_KEY_ID
+AWS_SECRET_ACCESS_KEY
+S3_BUCKET
+S3_PREFIX
+S3_REGION

builds/heroku-16.Dockerfile

@@ -3,7 +3,9 @@ FROM heroku/heroku:16-build
 WORKDIR /app
 ENV WORKSPACE_DIR="/app/builds" \
     S3_BUCKET="lang-python" \
-    S3_PREFIX="heroku-16/"
+    S3_PREFIX="heroku-16/" \
+    DEBIAN_FRONTEND=noninteractive \
+    STACK="heroku-16"
 
 RUN apt-get update && apt-get install -y python-pip && rm -rf /var/lib/apt/lists/*
 

builds/heroku-18.Dockerfile

@@ -0,0 +1,15 @@
+FROM heroku/heroku:18-build.v16
+
+WORKDIR /app
+ENV WORKSPACE_DIR="/app/builds" \
+    S3_BUCKET="lang-python" \
+    S3_PREFIX="heroku-18/" \
+    DEBIAN_FRONTEND=noninteractive \
+    STACK="heroku-18"
+
+RUN apt-get update && apt-get install --no-install-recommends -y python-pip-whl=9.0.1-2 python-pip=9.0.1-2 python-setuptools python-wheel && rm -rf /var/lib/apt/lists/*
+
+COPY requirements.txt /app/
+RUN pip install --disable-pip-version-check --no-cache-dir -r /app/requirements.txt
+
+COPY . /app

builds/runtimes/pypy

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+
+# fail hard
+set -o pipefail
+# fail harder
+set -eu
+
+OUT_PREFIX=$1
+
+dep_formula=${0#$WORKSPACE_DIR/} # this is the original script, e.g. pypy-5.3.1
+dep_name=$(basename $BASH_SOURCE) # this is us
+dep_version=${dep_formula##*"/${dep_name}-"} # "subtract" our name from full version name
+dep_package=${dep_name}2-v${dep_version} # it's always "pypy2-…"
+dep_dirname=${dep_package}-linux64
+dep_archive_name=${dep_dirname}.tar.bz2
+dep_url=https://bitbucket.org/pypy/pypy/downloads/${dep_archive_name}
+
+echo "Building PyPy…"
+
+curl -L "${dep_url}" | tar jx -C "${OUT_PREFIX}" --strip-components 1 # extract to $OUT_PREFIX, drop the first directory level, which is the archive name
+
+ln "$OUT_PREFIX/bin/pypy" "$OUT_PREFIX/bin/python"

builds/runtimes/pypy-5.3.1

@@ -2,13 +2,4 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-# NOTICE: This formula only works for the cedar-14 stack, not cedar.
-
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.3.1-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy2-v5.3.1-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy $OUT_PREFIX/bin/python
+source $(dirname $0)/pypy

builds/runtimes/pypy-5.6.0

@@ -2,13 +2,4 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-# NOTICE: This formula only works for the cedar-14 stack, not cedar.
-
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.6.0-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy2-v5.6.0-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy $OUT_PREFIX/bin/python
+source $(dirname $0)/pypy

builds/runtimes/pypy-5.7.0

@@ -2,13 +2,4 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-# NOTICE: This formula only works for the cedar-14 and heroku-16 stacks, not cedar.
-
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.7.0-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy2-v5.7.0-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy $OUT_PREFIX/bin/python
+source $(dirname $0)/pypy

builds/runtimes/pypy-5.7.1

@@ -2,13 +2,4 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-# NOTICE: This formula only works for the cedar-14 stack, not cedar.
-
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.7.1-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy2-v5.7.1-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy $OUT_PREFIX/bin/python
+source $(dirname $0)/pypy

builds/runtimes/pypy-5.8.0

@@ -2,11 +2,4 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy2-v5.8.0-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy2-v5.8.0-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy $OUT_PREFIX/bin/python
+source $(dirname $0)/pypy

builds/runtimes/pypy3

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+
+# fail hard
+set -o pipefail
+# fail harder
+set -eu
+
+OUT_PREFIX=$1
+
+dep_formula=${0#$WORKSPACE_DIR/} # this is the original script, e.g. pypy-5.3.1
+dep_name=$(basename $BASH_SOURCE) # this is us
+dep_version=${dep_formula##*"/${dep_name}-"} # "subtract" our name from full version name
+dep_package=${dep_name}${dep_version_prefix:-}-v${dep_version}${dep_version_suffix:-}
+dep_dirname=${dep_package}-linux64
+dep_archive_name=${dep_dirname}.tar.bz2
+dep_url=https://bitbucket.org/pypy/pypy/downloads/${dep_archive_name}
+
+echo "Building PyPy3…"
+
+curl -L "${dep_url}" | tar jx -C "${OUT_PREFIX}" --strip-components 1 # extract to $OUT_PREFIX, drop the first directory level, which is the archive name
+
+ln "$OUT_PREFIX/bin/pypy3" "$OUT_PREFIX/bin/python"

builds/runtimes/pypy3-2.4.0

@@ -2,13 +2,4 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-# NOTICE: This formula only works for the cedar-14 stack, not cedar.
-
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy3-2.4.0-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy3-2.4.0-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy3 $OUT_PREFIX/bin/python
+source $(dirname $0)/pypy3

builds/runtimes/pypy3-5.5.0

@@ -2,13 +2,7 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-# NOTICE: This formula only works for the cedar-14 stack, not cedar.
-
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy3.3-v5.5.0-alpha-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy3-v5.5.0-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy3 $OUT_PREFIX/bin/python
+# version pypy3-5.5.0 is really called pypy3.3-v5.5.0-alpha
+dep_version_prefix=".3"
+dep_version_suffix="-alpha"
+source $(dirname $0)/pypy3

builds/runtimes/pypy3-5.7.1

@@ -2,11 +2,4 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy3-v5.7.1-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy3-v5.7.1-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy3 $OUT_PREFIX/bin/python
+source $(dirname $0)/pypy3

builds/runtimes/pypy3-5.8.0

@@ -2,11 +2,4 @@
 # Build Path: /app/.heroku/python/
 # Build Deps: libraries/sqlite
 
-OUT_PREFIX=$1
-
-echo "Building PyPy…"
-SOURCE_TARBALL='https://bitbucket.org/pypy/pypy/downloads/pypy3-v5.8.0-linux64.tar.bz2'
-curl -L $SOURCE_TARBALL | tar jx
-cp -R pypy3-v5.8.0-linux64/* $OUT_PREFIX
-
-ln $OUT_PREFIX/bin/pypy3 $OUT_PREFIX/bin/python
+source $(dirname $0)/pypy3

builds/runtimes/python-2.7.16

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/2.7.16/Python-2.7.16.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-2.7.16 src
+cd src
+
+./configure --prefix=$OUT_PREFIX  --enable-unicode=ucs4 --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +

builds/runtimes/python-2.7.17

@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/2.7.17/Python-2.7.17.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-2.7.17 src
+cd src
+
+./configure --prefix=$OUT_PREFIX  --enable-unicode=ucs4 --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +

builds/runtimes/python-3.4.10

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.2/Python-3.7.2.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.2 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.4.9

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.4.9/Python-3.4.9.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.4.9 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.5.6

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.5.6/Python-3.5.6.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.5.6 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.5.7

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.5.7/Python-3.5.7.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.5.7 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.6.7

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.6.7/Python-3.6.7.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.6.7 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.6.8

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.6.8/Python-3.6.8.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.6.8 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.6.9

@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+# Build Deps: libraries/sqlite
+
+source $(dirname $0)/python3

builds/runtimes/python-3.7.1

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.1/Python-3.7.1.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.1 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.7.2

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.2/Python-3.7.2.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.2 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.7.3

@@ -0,0 +1,32 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python…"
+SOURCE_TARBALL='https://python.org/ftp/python/3.7.3/Python-3.7.3.tgz'
+curl -L $SOURCE_TARBALL | tar xz
+mv Python-3.7.3 src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

builds/runtimes/python-3.7.4

@@ -0,0 +1,5 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+# Build Deps: libraries/sqlite
+
+source $(dirname $0)/python3

builds/runtimes/python-3.7.5

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+source $(dirname $0)/python3

builds/runtimes/python-3.8.0

@@ -0,0 +1,4 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+source $(dirname $0)/python3

builds/runtimes/python2

@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+# Build Path: /app/.heroku/python/
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# Orient ourselves and build download link
+dep_formula=${0#$WORKSPACE_DIR/} # this is the original script, e.g. pypy-5.3.1
+BASE=${dep_formula##*/} # this gives us relative path
+python_version=${BASE^} # this gives us only the filename with version number
+version_number=$(echo "$python_version" | cut -d- -f2) # this returns just X.X.X
+dep_url=https://python.org/ftp/python/${version_number}/${python_version}.tgz
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python 3..."
+echo "Pulling from source: ${dep_url}"
+
+curl -L "${dep_url}" | tar xz -C "${OUT_PREFIX}"
+mv "${OUT_PREFIX}/${python_version}" src
+cd src
+
+./configure --prefix=$OUT_PREFIX  --enable-unicode=ucs4 --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +

builds/runtimes/python3

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+
+# fail hard
+set -o pipefail
+# fail harder
+set -eu
+
+OUT_PREFIX=$1
+BIN_DIR="$(cd "$(dirname "$0")"/../.. || exit; pwd)/bin"
+export BIN_DIR
+
+# Orient ourselves and build download link
+dep_formula=${0#$WORKSPACE_DIR/} # this is the original script, e.g. pypy-5.3.1
+BASE=${dep_formula##*/} # this gives us relative path
+python_version=${BASE^} # this gives us only the filename with version number
+version_number=$(echo "$python_version" | cut -d- -f2) # this returns just X.X.X
+dep_url=https://python.org/ftp/python/${version_number}/${python_version}.tgz
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/steps/sqlite3"
+
+sqlite3_version
+echo "Setting up SQLite3 Headers for $SQLITE3_VERSION"
+sqlite3_install "$OUT_PREFIX" "$SQLITE3_VERSION" 1
+
+echo "Building Python 3..."
+echo "Pulling from source: ${dep_url}"
+
+
+curl -L "${dep_url}" | tar xz -C "${OUT_PREFIX}"
+mv "${OUT_PREFIX}/${python_version}" src
+cd src
+
+./configure --prefix=$OUT_PREFIX --with-ensurepip=no
+make
+make install
+
+# Remove unneeded test directories, similar to the official Docker Python images:
+# https://github.com/docker-library/python
+find "${OUT_PREFIX}" \( -type d -a \( -name test -o -name tests \) \) -exec rm -rf '{}' +
+
+# Remove spare /
+LOCATION=${OUT_PREFIX%?}
+
+ln $LOCATION/bin/python3 $LOCATION/bin/python

requirements.txt

@@ -1,3 +1,3 @@
 docopt==0.6.2
-bob-builder==0.0.13
+bob-builder
 boto==2.48.0

spec/hatchet/python_spec.rb

@@ -4,7 +4,7 @@ describe "Python!!!!!!!!!!!" do
   it "🐍" do
     Hatchet::Runner.new('python-getting-started', stack: DEFAULT_STACK).deploy do |app|
       expect(app.output).to           match(/Installing pip/)
-      expect(app.run('python -V')).to match(/3.6.6/)
+      expect(app.run('python -V')).to match(/3.6.9/)
     end
   end
 end

spec/spec_helper.rb

@@ -1,4 +1,4 @@
-ENV['HATCHET_BUILDPACK_BASE'] = 'https://github.com/heroku/heroku-buildpack-python.git'
+ENV['HATCHET_BUILDPACK_BASE'] = 'https://github.com/' + ENV['TRAVIS_REPO_SLUG'] + '.git'
 
 require 'rspec/core'
 require 'rspec/retry'

test/fixtures/airflow/requirements.txt

@@ -1 +1 @@
-apache-airflow==1.10
+apache-airflow==1.10.2

test/fixtures/pipenv-version/Pipfile

@@ -6,4 +6,4 @@ verify_ssl = true
 requests = "*"
 
 [requires]
-python_version = "3.6"
+python_version = "3.6"

test/fixtures/pipenv-version2/Pipfile

@@ -0,0 +1,11 @@
+[[source]]
+url = "https://pypi.org/simple"
+verify_ssl = true
+name = "pypi"
+
+[packages]
+
+[dev-packages]
+
+[requires]
+python_version = "2.7"

test/fixtures/pipenv-version2/Pipfile.lock

@@ -0,0 +1,20 @@
+{
+    "_meta": {
+        "hash": {
+            "sha256": "ae4bdd7d4157baab65ae9d0e8389a6011e6b640995372c45ec81fa5d1ddfae9f"
+        },
+        "pipfile-spec": 6,
+        "requires": {
+            "python_version": "2.7"
+        },
+        "sources": [
+            {
+                "name": "pypi",
+                "url": "https://pypi.org/simple",
+                "verify_ssl": true
+            }
+        ]
+    },
+    "default": {},
+    "develop": {}
+}

test/fixtures/pysqlite/requirements.txt

@@ -0,0 +1 @@
+pysqlite

test/fixtures/pysqlite/runtime.txt

@@ -0,0 +1 @@
+python-2.7.16

test/fixtures/python2/runtime.txt

@@ -1 +1 @@
-python-2.7.15
+python-2.7.17

test/fixtures/python2_fail/runtime.txt

@@ -0,0 +1 @@
+python-2.7.99

test/fixtures/python2_warn/requirements.txt

@@ -0,0 +1 @@
+requests

test/fixtures/python2_warn/runtime.txt

@@ -0,0 +1 @@
+python-2.7.15

test/fixtures/python3_4/requirements.txt

@@ -0,0 +1 @@
+flask

test/fixtures/python3_4/runtime.txt

@@ -0,0 +1 @@
+python-3.4.9

test/fixtures/python3_4_fail/requirements.txt

@@ -0,0 +1 @@
+flask

test/fixtures/python3_4_fail/runtime.txt

@@ -0,0 +1 @@
+python-3.4.99

test/fixtures/python3_4_warn/requirements.txt

@@ -0,0 +1 @@
+flask

test/fixtures/python3_4_warn/runtime.txt

@@ -0,0 +1 @@
+python-3.4.9

test/fixtures/python3_5/requirements.txt

@@ -0,0 +1 @@
+requests

test/fixtures/python3_5/runtime.txt

@@ -0,0 +1 @@
+python-3.5.6

test/fixtures/python3_5_fail/requirements.txt

@@ -0,0 +1 @@
+flask

test/fixtures/python3_5_fail/runtime.txt

@@ -0,0 +1 @@
+python-3.5.99

test/fixtures/python3_5_warn/requirements.txt

@@ -0,0 +1 @@
+flask

test/fixtures/python3_5_warn/runtime.txt

@@ -0,0 +1 @@
+python-3.5.3

test/fixtures/python3_6/requirements.txt

@@ -0,0 +1 @@
+requests

test/fixtures/python3_6/runtime.txt

@@ -0,0 +1 @@
+python-3.6.8

test/fixtures/python3_6_fail/requirements.txt

@@ -0,0 +1 @@
+flask

test/fixtures/python3_6_fail/runtime.txt

@@ -0,0 +1 @@
+python-3.6.99

test/fixtures/python3_6_warn/requirements.txt

@@ -0,0 +1 @@
+requests

test/fixtures/python3_6_warn/runtime.txt

@@ -0,0 +1 @@
+python-3.6.7

test/fixtures/python3_7/requirements.txt

@@ -0,0 +1 @@
+requests

test/fixtures/python3_7/runtime.txt

@@ -0,0 +1 @@
+python-3.7.2

test/fixtures/python3_7_fail/requirements.txt

@@ -0,0 +1 @@
+flask

test/fixtures/python3_7_fail/runtime.txt

@@ -0,0 +1 @@
+python-3.7.99

test/fixtures/python3_7_warn/requirements.txt

@@ -0,0 +1 @@
+requests

test/fixtures/python3_7_warn/runtime.txt

@@ -0,0 +1 @@
+python-3.7.1

test/fixtures/python3_8/requirements.txt

@@ -0,0 +1 @@
+requests

test/fixtures/python3_8/runtime.txt

@@ -0,0 +1 @@
+python-3.8.0

test/fixtures/python3_8_fail/requirements.txt

@@ -0,0 +1 @@
+flask

test/fixtures/python3_8_fail/runtime.txt

@@ -0,0 +1 @@
+python-3.8.99

test/fixtures/pythonDefault/requirements.txt

@@ -0,0 +1 @@
+flask

test/run

@@ -1,186 +0,0 @@
-#!/usr/bin/env bash
-
-testAirflow() {
-  export SLUGIFY_USES_TEXT_UNIDECODE="yes"
-  compile "airflow"
-  assertCaptured "apache-airflow==1.10"
-  assertCapturedSuccess
-}
-
-testPipenv() {
-  compile "pipenv"
-  assertCapturedSuccess
-}
-
-testPipenvLock() {
-  compile "pipenv-lock"
-  assertCapturedSuccess
-}
-
-testPipenvVersion() {
-  compile "pipenv-version"
-  assertCaptured "3.6.6"
-  assertCapturedSuccess
-}
-
-testPipenvFullVersion() {
-  compile "pipenv-full-version"
-  assertCaptured "3.6.3"
-  assertCapturedSuccess
-}
-
-testNoRequirements() {
-  compile "no-requirements"
-  assertCapturedError
-}
-
-testCollectstatic() {
-  compile "collectstatic"
-  assertCaptured "collectstatic"
-}
-
-testGEOS() {
-  BUILD_WITH_GEO_LIBRARIES=1 compile "geos"
-  assertCaptured "geos"
-  assertCapturedSuccess
-}
-
-testNLTK() {
-  # NOTE: This is a RuntimeWarning emitted by Python 3's runpy.py script
-  # which is what is used when you call `python -m <module>`. This is due to
-  # how nltk imports things. It's not actually an error, but it would probably
-  # be bad to silence in Production.
-  export PYTHONWARNINGS="ignore::RuntimeWarning"
-  compile "nltk"
-  assertCaptured "Downloading NLTK packages: city_database stopwords"
-  assertCapturedSuccess
-}
-
-testSetupPy() {
-  compile "setup-py"
-  assertCaptured "maya"
-  assertCapturedSuccess
-}
-
-
-testStandardRequirements() {
-  compile "requirements-standard"
-  assertCaptured "requests"
-  assertCapturedSuccess
-}
-
-testPsycopg2() {
-  compile "psycopg2"
-  assertCaptured "psycopg2"
-  assertCapturedSuccess
-}
-
-testCffi() {
-  compile "cffi"
-  assertCaptured "cffi"
-  assertCapturedSuccess
-}
-
-testPylibmc() {
-  compile "pylibmc"
-  assertCaptured "pylibmc"
-  assertCapturedSuccess
-}
-
-testPython2() {
-    compile "python2"
-    assertCaptured "python-2.7.15"
-    assertCapturedSuccess
-}
-
-testPython3() {
-  compile "python3"
-  assertCaptured "python-3.6.6"
-  assertCapturedSuccess
-}
-
-testGitEgg() {
-  compile "git-egg"
-  assertCaptured "requests"
-  assertCapturedSuccess
-}
-
-testSmartRequirements() {
-  local cache_dir="$(mktmpdir)"
-  compile "requirements-standard" "$cache_dir"
-  assertFile "requests" ".heroku/python/requirements-declared.txt"
-  assertCapturedSuccess
-  compile "psycopg2" "$cache_dir"
-  assertCaptured "Uninstalling requests"
-  assertFile "psycopg2" ".heroku/python/requirements-declared.txt"
-  assertCapturedSuccess
-}
-
-testStackChange() {
-  local cache_dir="$(mktmpdir)"
-  mkdir -p "${cache_dir}/.heroku"
-  echo "different-stack" > "${cache_dir}/.heroku/python-stack"
-  compile "requirements-standard" "$cache_dir"
-  assertCaptured "clearing cache"
-  assertFile "$STACK" ".heroku/python-stack"
-  assertCapturedSuccess
-}
-
-
-pushd $(dirname 0) >/dev/null
-popd >/dev/null
-
-source $(pwd)/test/utils
-
-mktmpdir() {
-  dir=$(mktemp -t testXXXXX)
-  rm -rf $dir
-  mkdir $dir
-  echo $dir
-}
-
-detect() {
-  capture $(pwd)/bin/detect $(pwd)/test/fixtures/$1
-}
-
-compile_dir=""
-
-default_process_types_cleanup() {
-  file="/tmp/default_process_types"
-  if [ -f "$file" ]; then
-    rm "$file"
-  fi
-}
-
-compile() {
-  default_process_types_cleanup
-  bp_dir=$(mktmpdir)
-  compile_dir=$(mktmpdir)
-  cp -a $(pwd)/* ${bp_dir}
-  cp -a ${bp_dir}/test/fixtures/$1/. ${compile_dir}
-  capture ${bp_dir}/bin/compile ${compile_dir} ${2:-$(mktmpdir)} $3
-}
-
-compileDir() {
-  default_process_types_cleanup
-
-  local bp_dir=$(mktmpdir)
-  local compile_dir=${1:-$(mktmpdir)}
-  local cache_dir=${2:-$(mktmpdir)}
-  local env_dir=$3
-
-  cp -a $(pwd)/* ${bp_dir}
-  capture ${bp_dir}/bin/compile ${compile_dir} ${cache_dir} ${env_dir}
-}
-
-release() {
-  bp_dir=$(mktmpdir)
-  cp -a $(pwd)/* ${bp_dir}
-  capture ${bp_dir}/bin/release ${bp_dir}/test/fixtures/$1
-}
-
-assertFile() {
-  assertEquals "$1" "$(cat ${compile_dir}/$2)"
-}
-
-source $(pwd)/test/shunit2

test/run-deps

@@ -0,0 +1,65 @@
+#!/usr/bin/env bash
+
+# Default Python Versions
+# shellcheck source=bin/default_pythons
+source "bin/default_pythons"
+
+testAirflow() {
+  export SLUGIFY_USES_TEXT_UNIDECODE="yes"
+  compile "airflow"
+  assertCaptured "apache-airflow==1.10.2"
+  assertCapturedSuccess
+}
+
+testCollectstatic() {
+  compile "collectstatic"
+  assertCaptured "collectstatic"
+}
+
+testGEOS() {
+  export BUILD_WITH_GEO_LIBRARIES=1
+  compile "geos"
+  assertCaptured "geos"
+  assertCapturedSuccess
+}
+
+testNLTK() {
+  # NOTE: This is a RuntimeWarning emitted by Python 3's runpy.py script
+  # which is what is used when you call `python -m <module>`. This is due to
+  # how nltk imports things. It's not actually an error, but it would probably
+  # be bad to silence in Production.
+  export PYTHONWARNINGS="ignore::RuntimeWarning"
+  compile "nltk"
+  assertCaptured "[nltk_data] Downloading package city_database" "STD_ERR"
+  assertCapturedSuccess
+}
+
+testPsycopg2() {
+  compile "psycopg2"
+  assertCaptured "psycopg2"
+  assertCapturedSuccess
+}
+
+testPysqlite() {
+  compile "pysqlite"
+  assertCaptured "pysqlite"
+  assertCapturedSuccess
+}
+
+testCffi() {
+  compile "cffi"
+  assertCaptured "cffi"
+  assertCapturedSuccess
+}
+
+testPylibmc() {
+  compile "pylibmc"
+  assertCaptured "pylibmc"
+  assertCapturedSuccess
+}
+
+pushd $(dirname 0) >/dev/null
+popd >/dev/null
+
+source $(pwd)/test/utils
+source $(pwd)/test/shunit2