From 3ebeb57686232ba22af16e8aad7fe321d5a347c0 Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Wed, 21 Aug 2019 19:11:57 +0200
Subject: [PATCH 01/10] Support pyproject.toml when detecting Python apps

---
 bin/detect | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bin/detect b/bin/detect
index eeb965b0..682585fc 100755
--- a/bin/detect
+++ b/bin/detect
@@ -15,7 +15,7 @@
 BUILD_DIR=$1
 
 # Exit early if app is clearly not Python.
-if [ ! -f "$BUILD_DIR/requirements.txt" ] && [ ! -f "$BUILD_DIR/setup.py" ] && [ ! -f "$BUILD_DIR/Pipfile" ]; then
+if [ ! -f "$BUILD_DIR/requirements.txt" ] && [ ! -f "$BUILD_DIR/setup.py" ] && [ ! -f "$BUILD_DIR/Pipfile" ] && [ ! -f "$BUILD_DIR/pyproject.toml" ]; then
   exit 1
 fi
 

From d20ddf87f36f9e4f4a4c4e44a18bb8125b32bf56 Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Thu, 22 Aug 2019 13:16:08 +0200
Subject: [PATCH 02/10] Avoid editable installs for pyproject.toml-style
 projects

---
 bin/compile | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/bin/compile b/bin/compile
index db2d838b..6e30856b 100755
--- a/bin/compile
+++ b/bin/compile
@@ -269,8 +269,13 @@ mtime "pip.uninstall.time" "${start}"
 # This allows for people to ship a setup.py application to Heroku
 # (which is rare, but I vouch that it should work!)
 
-if [ ! -f requirements.txt ] && [ ! -f Pipfile ]; then
-  echo "-e ." > requirements.txt
+if [ ! -f requirements.txt ] && [ ! -f Pipfile ] ; then
+    if [ -f pyproject.toml ] ; then
+        # Editable installs are not supported for pyproject.toml-style projects.
+        echo "." > requirements.txt
+    else
+        echo "-e ." > requirements.txt
+    fi
 fi
 
 # Fix egg-links.

From 0422f568e407837f7da6b59bece7c17b262ac41d Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Wed, 21 Aug 2019 21:41:20 +0200
Subject: [PATCH 03/10] Add tests for pyproject.toml-style projects using
 poetry

Add two test cases for projects using poetry as the build backend:

- testPoetry: project without dependencies

- testPoetryLock: project with dependencies, using a poetry.lock file
---
 test/fixtures/poetry-lock/foobar.py      |  0
 test/fixtures/poetry-lock/poetry.lock    | 19 +++++++++++++++++++
 test/fixtures/poetry-lock/pyproject.toml | 15 +++++++++++++++
 test/fixtures/poetry/foobar.py           |  0
 test/fixtures/poetry/pyproject.toml      | 14 ++++++++++++++
 test/run-features                        | 10 ++++++++++
 6 files changed, 58 insertions(+)
 create mode 100644 test/fixtures/poetry-lock/foobar.py
 create mode 100644 test/fixtures/poetry-lock/poetry.lock
 create mode 100644 test/fixtures/poetry-lock/pyproject.toml
 create mode 100644 test/fixtures/poetry/foobar.py
 create mode 100644 test/fixtures/poetry/pyproject.toml

diff --git a/test/fixtures/poetry-lock/foobar.py b/test/fixtures/poetry-lock/foobar.py
new file mode 100644
index 00000000..e69de29b
diff --git a/test/fixtures/poetry-lock/poetry.lock b/test/fixtures/poetry-lock/poetry.lock
new file mode 100644
index 00000000..3eb16032
--- /dev/null
+++ b/test/fixtures/poetry-lock/poetry.lock
@@ -0,0 +1,19 @@
+[[package]]
+category = "main"
+description = "Classes Without Boilerplate"
+name = "attrs"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "19.1.0"
+
+[package.extras]
+dev = ["coverage", "hypothesis", "pympler", "pytest", "six", "zope.interface", "sphinx", "pre-commit"]
+docs = ["sphinx", "zope.interface"]
+tests = ["coverage", "hypothesis", "pympler", "pytest", "six", "zope.interface"]
+
+[metadata]
+content-hash = "9c92739040d45f898575877e69198d92bb9477423fe80c60a14376bf1f3d010e"
+python-versions = "^3.7"
+
+[metadata.hashes]
+attrs = ["69c0dbf2ed392de1cb5ec704444b08a5ef81680a61cb899dc08127123af36a79", "f0b870f674851ecbfbbbd364d6b5cbdff9dcedbc7f3f5e18a6891057f21fe399"]
diff --git a/test/fixtures/poetry-lock/pyproject.toml b/test/fixtures/poetry-lock/pyproject.toml
new file mode 100644
index 00000000..0a3fd420
--- /dev/null
+++ b/test/fixtures/poetry-lock/pyproject.toml
@@ -0,0 +1,15 @@
+[tool.poetry]
+name = "foobar"
+version = "0.1.0"
+description = ""
+authors = ["Your Name <you@example.com>"]
+
+[tool.poetry.dependencies]
+python = "^3.6"
+attrs = "^19.1.0"
+
+[tool.poetry.dev-dependencies]
+
+[build-system]
+requires = ["poetry>=0.12"]
+build-backend = "poetry.masonry.api"
diff --git a/test/fixtures/poetry/foobar.py b/test/fixtures/poetry/foobar.py
new file mode 100644
index 00000000..e69de29b
diff --git a/test/fixtures/poetry/pyproject.toml b/test/fixtures/poetry/pyproject.toml
new file mode 100644
index 00000000..4074cf7f
--- /dev/null
+++ b/test/fixtures/poetry/pyproject.toml
@@ -0,0 +1,14 @@
+[tool.poetry]
+name = "foobar"
+version = "0.1.0"
+description = ""
+authors = ["Your Name <you@example.com>"]
+
+[tool.poetry.dependencies]
+python = "^3.6"
+
+[tool.poetry.dev-dependencies]
+
+[build-system]
+requires = ["poetry>=0.12"]
+build-backend = "poetry.masonry.api"
diff --git a/test/run-features b/test/run-features
index 66fac4ea..54b195a8 100755
--- a/test/run-features
+++ b/test/run-features
@@ -70,6 +70,16 @@ testPipenvFullVersion() {
   assertCapturedSuccess
 }
 
+testPoetry() {
+    compile "poetry"
+    assertCapturedSuccess
+}
+
+testPoetryLock() {
+    compile "poetry-lock"
+    assertCapturedSuccess
+}
+
 testNoRequirements() {
   compile "no-requirements"
   assertCapturedError

From 7a65ab1b7d00cc2b390defd7b250ca93f433330f Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Thu, 22 Aug 2019 18:14:10 +0200
Subject: [PATCH 04/10] Add tests for pyproject.toml-style projects using flit

Add two test cases for projects using flit as the build backend:

- testFlit: project without dependencies

- testFlitRequires: project with dependencies
---
 test/fixtures/flit-requires/foobar.py      |  3 +++
 test/fixtures/flit-requires/pyproject.toml | 10 ++++++++++
 test/fixtures/flit/foobar.py               |  3 +++
 test/fixtures/flit/pyproject.toml          |  9 +++++++++
 test/run-features                          | 10 ++++++++++
 5 files changed, 35 insertions(+)
 create mode 100644 test/fixtures/flit-requires/foobar.py
 create mode 100644 test/fixtures/flit-requires/pyproject.toml
 create mode 100644 test/fixtures/flit/foobar.py
 create mode 100644 test/fixtures/flit/pyproject.toml

diff --git a/test/fixtures/flit-requires/foobar.py b/test/fixtures/flit-requires/foobar.py
new file mode 100644
index 00000000..4b4c6781
--- /dev/null
+++ b/test/fixtures/flit-requires/foobar.py
@@ -0,0 +1,3 @@
+"""An amazing sample package!"""
+
+__version__ = '0.1'
diff --git a/test/fixtures/flit-requires/pyproject.toml b/test/fixtures/flit-requires/pyproject.toml
new file mode 100644
index 00000000..61cc974f
--- /dev/null
+++ b/test/fixtures/flit-requires/pyproject.toml
@@ -0,0 +1,10 @@
+[build-system]
+requires = ["flit"]
+build-backend = "flit.buildapi"
+
+[tool.flit.metadata]
+module = "foobar"
+author = "Sir Robin"
+author-email = "robin@camelot.uk"
+home-page = "https://github.com/sirrobin/foobar"
+requires = ["attrs >=19.1.0"]
diff --git a/test/fixtures/flit/foobar.py b/test/fixtures/flit/foobar.py
new file mode 100644
index 00000000..4b4c6781
--- /dev/null
+++ b/test/fixtures/flit/foobar.py
@@ -0,0 +1,3 @@
+"""An amazing sample package!"""
+
+__version__ = '0.1'
diff --git a/test/fixtures/flit/pyproject.toml b/test/fixtures/flit/pyproject.toml
new file mode 100644
index 00000000..3dca8c95
--- /dev/null
+++ b/test/fixtures/flit/pyproject.toml
@@ -0,0 +1,9 @@
+[build-system]
+requires = ["flit"]
+build-backend = "flit.buildapi"
+
+[tool.flit.metadata]
+module = "foobar"
+author = "Sir Robin"
+author-email = "robin@camelot.uk"
+home-page = "https://github.com/sirrobin/foobar"
diff --git a/test/run-features b/test/run-features
index 54b195a8..5c4b1b16 100755
--- a/test/run-features
+++ b/test/run-features
@@ -80,6 +80,16 @@ testPoetryLock() {
     assertCapturedSuccess
 }
 
+testFlit() {
+    compile "flit"
+    assertCapturedSuccess
+}
+
+testFlitRequires() {
+    compile "flit-requires"
+    assertCapturedSuccess
+}
+
 testNoRequirements() {
   compile "no-requirements"
   assertCapturedError

From 42c45ee50c20ef4f75fc296d1e2bb4e82e2bdcce Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Wed, 28 Aug 2019 09:48:06 +0200
Subject: [PATCH 05/10] Add test for pyproject.toml-style project using
 setuptools

---
 test/fixtures/pyproject-toml/pyproject.toml | 3 +++
 test/fixtures/pyproject-toml/setup.py       | 4 ++++
 test/run-features                           | 5 +++++
 3 files changed, 12 insertions(+)
 create mode 100644 test/fixtures/pyproject-toml/pyproject.toml
 create mode 100644 test/fixtures/pyproject-toml/setup.py

diff --git a/test/fixtures/pyproject-toml/pyproject.toml b/test/fixtures/pyproject-toml/pyproject.toml
new file mode 100644
index 00000000..864b334a
--- /dev/null
+++ b/test/fixtures/pyproject-toml/pyproject.toml
@@ -0,0 +1,3 @@
+[build-system]
+requires = ["setuptools", "wheel"]
+build-backend = "setuptools.build_meta:__legacy__"
diff --git a/test/fixtures/pyproject-toml/setup.py b/test/fixtures/pyproject-toml/setup.py
new file mode 100644
index 00000000..4d986d25
--- /dev/null
+++ b/test/fixtures/pyproject-toml/setup.py
@@ -0,0 +1,4 @@
+from setuptools import setup
+
+
+setup(name="foobar", version="1.0.0")
diff --git a/test/run-features b/test/run-features
index 5c4b1b16..3c7b168f 100755
--- a/test/run-features
+++ b/test/run-features
@@ -70,6 +70,11 @@ testPipenvFullVersion() {
   assertCapturedSuccess
 }
 
+testPyProjectToml() {
+    compile "pyproject-toml"
+    assertCapturedSuccess
+}
+
 testPoetry() {
     compile "poetry"
     assertCapturedSuccess

From 13633dbb668d6aff2b30a436eb5ae2c2a71d20e0 Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Fri, 23 Aug 2019 10:10:08 +0200
Subject: [PATCH 06/10] Add failing test for poetry.lock

Check that pinned requirements are honored when poetry.lock is present.
Request an outdated version of marshmallow in poetry.lock (3.0.0). Check
that the outdated version is installed, rather than a newer version
also satisfying the version constraint in pyproject.toml (^3.0.0).
---
 test/fixtures/poetry-lock/poetry.lock    | 21 +++++++++++----------
 test/fixtures/poetry-lock/pyproject.toml |  2 +-
 test/run-features                        |  1 +
 3 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/test/fixtures/poetry-lock/poetry.lock b/test/fixtures/poetry-lock/poetry.lock
index 3eb16032..99cd77b4 100644
--- a/test/fixtures/poetry-lock/poetry.lock
+++ b/test/fixtures/poetry-lock/poetry.lock
@@ -1,19 +1,20 @@
 [[package]]
 category = "main"
-description = "Classes Without Boilerplate"
-name = "attrs"
+description = "A lightweight library for converting complex datatypes to and from native Python datatypes."
+name = "marshmallow"
 optional = false
-python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
-version = "19.1.0"
+python-versions = ">=3.5"
+version = "3.0.0"
 
 [package.extras]
-dev = ["coverage", "hypothesis", "pympler", "pytest", "six", "zope.interface", "sphinx", "pre-commit"]
-docs = ["sphinx", "zope.interface"]
-tests = ["coverage", "hypothesis", "pympler", "pytest", "six", "zope.interface"]
+dev = ["pytest", "pytz", "simplejson", "flake8 (3.7.8)", "flake8-bugbear (19.8.0)", "pre-commit (>=1.17,<2.0)", "tox"]
+docs = ["sphinx (2.2.0)", "sphinx-issues (1.2.0)", "alabaster (0.7.12)", "sphinx-version-warning (1.1.2)"]
+lint = ["flake8 (3.7.8)", "flake8-bugbear (19.8.0)", "pre-commit (>=1.17,<2.0)"]
+tests = ["pytest", "pytz", "simplejson"]
 
 [metadata]
-content-hash = "9c92739040d45f898575877e69198d92bb9477423fe80c60a14376bf1f3d010e"
-python-versions = "^3.7"
+content-hash = "11b18d7787605b57a1019436950c60105518d3f3a8a60030493402031355e2f2"
+python-versions = "^3.6"
 
 [metadata.hashes]
-attrs = ["69c0dbf2ed392de1cb5ec704444b08a5ef81680a61cb899dc08127123af36a79", "f0b870f674851ecbfbbbd364d6b5cbdff9dcedbc7f3f5e18a6891057f21fe399"]
+marshmallow = ["e5e9fd0c2e919b4ece915eb30808206349a49a45df72e99ed20e27a9053d574b", "fa2d8a4b61d09b0e161a14acc5ad8ab7aaaf1477f3dd52819ddd6c6c8275733a"]
\ No newline at end of file
diff --git a/test/fixtures/poetry-lock/pyproject.toml b/test/fixtures/poetry-lock/pyproject.toml
index 0a3fd420..85695c71 100644
--- a/test/fixtures/poetry-lock/pyproject.toml
+++ b/test/fixtures/poetry-lock/pyproject.toml
@@ -6,7 +6,7 @@ authors = ["Your Name <you@example.com>"]
 
 [tool.poetry.dependencies]
 python = "^3.6"
-attrs = "^19.1.0"
+marshmallow = "^3.0.0"
 
 [tool.poetry.dev-dependencies]
 
diff --git a/test/run-features b/test/run-features
index 3c7b168f..e452a6cb 100755
--- a/test/run-features
+++ b/test/run-features
@@ -82,6 +82,7 @@ testPoetry() {
 
 testPoetryLock() {
     compile "poetry-lock"
+    assertCaptured "marshmallow==3.0.0"
     assertCapturedSuccess
 }
 

From 4c9b95c51ada04a4f0532321145f0e29bfe72678 Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Wed, 28 Aug 2019 18:09:24 +0200
Subject: [PATCH 07/10] Do not write requirements.txt for pyproject.toml-based
 projects

Install pyproject.toml-based projects using `pip install .`. Do not use a
requirements.txt for this. The requirements.txt file is needed to handle pinned
versions extracted from the poetry.lock file.

Note that we cannot simply append `.` to the exported requirements.txt file.
Currently pip requires that either all requirements have a hash or none.
Including `.` would thus force us to omit hashes for all requirements.
---
 bin/compile             | 10 ++--------
 bin/steps/pip-install   | 23 ++++++++++++++++++-----
 bin/steps/pip-uninstall |  2 +-
 3 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/bin/compile b/bin/compile
index 6e30856b..8c9c9b22 100755
--- a/bin/compile
+++ b/bin/compile
@@ -268,14 +268,8 @@ mtime "pip.uninstall.time" "${start}"
 # If no requirements.txt file given, assume `setup.py develop` is intended.
 # This allows for people to ship a setup.py application to Heroku
 # (which is rare, but I vouch that it should work!)
-
-if [ ! -f requirements.txt ] && [ ! -f Pipfile ] ; then
-    if [ -f pyproject.toml ] ; then
-        # Editable installs are not supported for pyproject.toml-style projects.
-        echo "." > requirements.txt
-    else
-        echo "-e ." > requirements.txt
-    fi
+if [ ! -f requirements.txt ] && [ ! -f Pipfile ] && [ ! -f pyproject.toml ]; then
+    echo "-e ." > requirements.txt
 fi
 
 # Fix egg-links.
diff --git a/bin/steps/pip-install b/bin/steps/pip-install
index b950feff..7be26ebb 100755
--- a/bin/steps/pip-install
+++ b/bin/steps/pip-install
@@ -34,15 +34,26 @@ if [ ! "$SKIP_PIP_INSTALL" ]; then
     mcount "tool.pip"
 
     # Count expected build failures.
-    if grep -q '==0.0.0' requirements.txt; then
+    if [ -f requirements.txt ] && grep -q '==0.0.0' requirements.txt; 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]}"
+
+    if [ -f requirements.txt ]; then
+        /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="${PIPESTATUS[0]}"
+    else
+        PIP_STATUS=0
+    fi
+
+    if [ "$PIP_STATUS" -eq 0 ] && [ -f pyproject.toml ]; then
+        /app/.heroku/python/bin/pip install . --exists-action=w --disable-pip-version-check --no-cache-dir 2>&1 | tee -a "$WARNINGS_LOG" | cleanup | indent
+        PIP_STATUS="${PIPESTATUS[0]}"
+    fi
+
     set -e
 
     show-warnings
@@ -53,8 +64,10 @@ if [ ! "$SKIP_PIP_INSTALL" ]; then
     fi
 
     # Smart Requirements handling
-    cp requirements.txt .heroku/python/requirements-declared.txt
-    /app/.heroku/python/bin/pip freeze --disable-pip-version-check > .heroku/python/requirements-installed.txt
+    if [ -f requirements.txt ]; then
+        cp requirements.txt .heroku/python/requirements-declared.txt
+        /app/.heroku/python/bin/pip freeze --disable-pip-version-check > .heroku/python/requirements-installed.txt
+    fi
 
     echo
 
diff --git a/bin/steps/pip-uninstall b/bin/steps/pip-uninstall
index 2e1ad8db..ed5fae0c 100755
--- a/bin/steps/pip-uninstall
+++ b/bin/steps/pip-uninstall
@@ -5,7 +5,7 @@ set +e
 # shellcheck source=bin/utils
 source "$BIN_DIR/utils"
 
-if [ ! "$SKIP_PIP_INSTALL" ]; then
+if [ ! "$SKIP_PIP_INSTALL" ] && [ -f requirements.txt ]; then
 
   if [[ -f .heroku/python/requirements-declared.txt ]]; then
 

From 2614fabf4e1028375da92f08bd624c054e4467f4 Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Fri, 23 Aug 2019 16:58:32 +0200
Subject: [PATCH 08/10] Install pinned dependencies from poetry.lock

If a poetry.lock file is present, use the Poetry CLI to export the
pinned requirements to a requirements.txt file. If the project already
contains a requirements.txt, use that and ignore poetry.lock.

Poetry is not used to install the project because it does not clean up
stale requirements. This means that requirements need to be exported
anyway, for the `pip-uninstall` step.

Since we only use Poetry to export a requirements.txt file, ignore the
Poetry version specified in pyproject.toml. Install a pre-release of
1.0.0 because the export command is not available before 1.0.0a0.

Note that supporting pyproject.toml-based installations is not enough to
handle pinned requirements: When pip installs a pyproject.toml-style
project using the process described in PEP 517, it only uses Poetry to
build a wheel. The wheel contains the version constraints from
pyproject.toml, not the pinned versions from poetry.lock.
---
 bin/compile      |  4 +++
 bin/steps/poetry | 63 ++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 bin/steps/poetry

diff --git a/bin/compile b/bin/compile
index 8c9c9b22..df9e79f5 100755
--- a/bin/compile
+++ b/bin/compile
@@ -257,6 +257,10 @@ mtime "python.install.time" "${start}"
 # shellcheck source=bin/steps/pipenv
 source "$BIN_DIR/steps/pipenv"
 
+# Export requirements.txt from poetry.lock, if present.
+# shellcheck source=bin/steps/poetry
+source "$BIN_DIR/steps/poetry"
+
 # Uninstall removed dependencies with Pip.
 # The buildpack will automatically remove any declared dependencies (in requirements.txt)
 # that were explicitly removed. This machinery is a bit complex, but it is not complicated.
diff --git a/bin/steps/poetry b/bin/steps/poetry
new file mode 100644
index 00000000..aed1fdc8
--- /dev/null
+++ b/bin/steps/poetry
@@ -0,0 +1,63 @@
+#!/usr/bin/env bash
+
+set -e
+
+# shellcheck source=bin/utils
+source "$BIN_DIR/utils"
+
+if [ ! -f requirements.txt ] && [ -f pyproject.toml ] && [ -f poetry.lock ]; then
+    # Measure that we're using Poetry.
+    mcount "tool.poetry"
+
+    # Hash poetry.lock to detect changes.
+    POETRY_LOCK_SHA=$(openssl dgst -sha256 poetry.lock)
+
+    # Use cached requirements.txt if poetry.lock is unchanged.
+    CACHED_REQUIREMENTS=$CACHE_DIR/requirements.txt
+    CACHED_POETRY_LOCK_SHA=$CACHE_DIR/poetry.lock.sha256
+
+    if [ -f "$CACHED_REQUIREMENTS" ] && [ -f "$CACHED_POETRY_LOCK_SHA" ] &&
+           [ "$POETRY_LOCK_SHA" == "$(cat "$CACHED_POETRY_LOCK_SHA")" ]; then
+        echo "Skipping requirements export, as poetry.lock hasn't changed since last deploy." | indent
+        cp "$CACHED_REQUIREMENTS" requirements.txt
+    else
+        # Set environment variables for pip
+        # This reads certain environment variables set on the Heroku app config
+        # and makes them accessible to the pip install process.
+        #
+        # PIP_EXTRA_INDEX_URL allows for an alternate pypi URL to be used.
+        if [[ -r "$ENV_DIR/PIP_EXTRA_INDEX_URL" ]]; then
+            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 "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE" ]]; then
+            SLUGIFY_USES_TEXT_UNIDECODE="$(cat "$ENV_DIR/SLUGIFY_USES_TEXT_UNIDECODE")"
+            export SLUGIFY_USES_TEXT_UNIDECODE
+            mcount "buildvar.SLUGIFY_USES_TEXT_UNIDECODE"
+        fi
+
+        # Install Poetry.
+        #
+        # Poetry is not used to install the project because it does not clean up
+        # stale requirements (see sdispater/poetry#648), so we need to export
+        # requirements.txt anyway for the pip-uninstall step.
+        #
+        # Since we only use Poetry to export a requirements.txt file, ignore the
+        # Poetry version specified in pyproject.toml. Install a pre-release of
+        # 1.0.0 because the export command is not available before 1.0.0a0.
+        export POETRY_VERSION="1.0.0b1"
+        puts-step "Exporting requirements with Poetry $POETRY_VERSION…"
+        /app/.heroku/python/bin/pip install "poetry==$POETRY_VERSION" \
+            --disable-pip-version-check &> /dev/null
+
+        # Export requirements.
+        /app/.heroku/python/bin/poetry export -f requirements.txt > requirements.txt
+
+        # Write SHA and requirements.txt to cache dir.
+        echo "$POETRY_LOCK_SHA" > "$CACHED_POETRY_LOCK_SHA"
+        cp requirements.txt "$CACHED_REQUIREMENTS"
+    fi
+fi

From 1d609a11ee8ad832f1ffbbff1733c08ef5d2eb06 Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Sun, 24 Nov 2019 15:24:00 +0100
Subject: [PATCH 09/10] Upgrade to poetry 1.0.0b7

---
 bin/steps/poetry | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bin/steps/poetry b/bin/steps/poetry
index aed1fdc8..2b51ac39 100644
--- a/bin/steps/poetry
+++ b/bin/steps/poetry
@@ -48,7 +48,7 @@ if [ ! -f requirements.txt ] && [ -f pyproject.toml ] && [ -f poetry.lock ]; the
         # Since we only use Poetry to export a requirements.txt file, ignore the
         # Poetry version specified in pyproject.toml. Install a pre-release of
         # 1.0.0 because the export command is not available before 1.0.0a0.
-        export POETRY_VERSION="1.0.0b1"
+        export POETRY_VERSION="1.0.0b7"
         puts-step "Exporting requirements with Poetry $POETRY_VERSION…"
         /app/.heroku/python/bin/pip install "poetry==$POETRY_VERSION" \
             --disable-pip-version-check &> /dev/null

From cd23a90c53281d86873954999d081bf2d75f397b Mon Sep 17 00:00:00 2001
From: Claudio Jolowicz <claudio.jolowicz@cyren.com>
Date: Sun, 24 Nov 2019 15:24:11 +0100
Subject: [PATCH 10/10] Use --output option instead of stream redirection

---
 bin/steps/poetry | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bin/steps/poetry b/bin/steps/poetry
index 2b51ac39..32ee98ab 100644
--- a/bin/steps/poetry
+++ b/bin/steps/poetry
@@ -54,7 +54,7 @@ if [ ! -f requirements.txt ] && [ -f pyproject.toml ] && [ -f poetry.lock ]; the
             --disable-pip-version-check &> /dev/null
 
         # Export requirements.
-        /app/.heroku/python/bin/poetry export -f requirements.txt > requirements.txt
+        /app/.heroku/python/bin/poetry export -f requirements.txt -o requirements.txt
 
         # Write SHA and requirements.txt to cache dir.
         echo "$POETRY_LOCK_SHA" > "$CACHED_POETRY_LOCK_SHA"