skip set if no path-links are found

commit 554a8bbae6
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 16:26:18 2016 -0500

    comment out debugging line

commit 6572ad3d44
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 16:21:03 2016 -0500

    test

commit 35cabaeebc
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 16:09:21 2016 -0500

    try .

commit 300285a92d
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 16:05:22 2016 -0500

    find

commit 7a6f1eb010
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 16:02:24 2016 -0500

    find

commit 66d754978e
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 15:55:04 2016 -0500

    fix xargs

commit 9c222a9350
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 15:53:04 2016 -0500

    copy src

commit 7f4273f47f
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 15:45:20 2016 -0500

    new replace script

commit dd707c21e3
Author: Kenneth Reitz <me@kennethreitz.org>
Date:   Mon Dec 19 15:40:35 2016 -0500

    re-write egg-links

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Python Buildpack Changelog
 
+## v89
+
+Improved cache functionality and fix egg-links regression. 
+
 ## v88
 
 Fixed bug with editable pip installations. 

bin/compile

@@ -27,9 +27,8 @@ BUILD_DIR=$1
 CACHE_DIR=$2
 ENV_DIR=$3
 
-# Static configurations for virtualenv caches.
-VIRTUALENV_LOC=".heroku/venv"
-LEGACY_TRIGGER="lib/python2.7"
+# Export path environment variables for sub-scripts.
+export BIN_DIR ROOT_DIR BUILD_DIR CACHE_DIR ENV_DIR
 
 DEFAULT_PYTHON_VERSION="python-2.7.13"
 DEFAULT_PYTHON_STACK="cedar-14"
@@ -133,21 +132,20 @@ fi
 # Prepare the cache.
 mkdir -p $CACHE_DIR
 
-# Purge "old-style" virtualenvs.
-bpwatch start clear_old_venvs
-  [ -d $CACHE_DIR/$LEGACY_TRIGGER ] && rm -fr $CACHE_DIR/.heroku/bin $CACHE_DIR/.heroku/lib $CACHE_DIR/.heroku/include
-  [ -d $CACHE_DIR/$VIRTUALENV_LOC ] && rm -fr $CACHE_DIR/.heroku/venv $CACHE_DIR/.heroku/src
-bpwatch stop clear_old_venvs
-
 # Restore old artifacts from the cache.
 bpwatch start restore_cache
-    mkdir -p .heroku
+  mkdir -p .heroku
+
+  cp -R $CACHE_DIR/.heroku/python .heroku/ &> /dev/null || true
+  cp -R $CACHE_DIR/.heroku/python-stack .heroku/ &> /dev/null || true
+  cp -R $CACHE_DIR/.heroku/python-version .heroku/ &> /dev/null || true
+  cp -R $CACHE_DIR/.heroku/vendor .heroku/ &> /dev/null || true
+  cp -R $CACHE_DIR/.heroku/venv .heroku/ &> /dev/null || true
+
+  if [[ -d $CACHE_DIR/.heroku/src ]]; then
+    cp -R $CACHE_DIR/.heroku/src .heroku/ &> /dev/null || true
+  fi
 
-    cp -R $CACHE_DIR/.heroku/python .heroku/ &> /dev/null || true
-    cp -R $CACHE_DIR/.heroku/python-stack .heroku/ &> /dev/null || true
-    cp -R $CACHE_DIR/.heroku/python-version .heroku/ &> /dev/null || true
-    cp -R $CACHE_DIR/.heroku/vendor .heroku/ &> /dev/null || true
-    cp -R $CACHE_DIR/.heroku/venv .heroku/ &> /dev/null || true
 
 bpwatch stop restore_cache
 
@@ -157,11 +155,12 @@ mkdir -p $(dirname $PROFILE_PATH)
 mkdir -p /app/.heroku/src
 
 if [[ $BUILD_DIR != '/app' ]]; then
-    # python expects to reside in /app, so set up symlinks
-    # we will not remove these later so subsequent buildpacks can still invoke it
-    ln -s $BUILD_DIR/.heroku/python /app/.heroku/python
-    ln -s $BUILD_DIR/.heroku/vendor /app/.heroku/vendor
-    ln -s $BUILD_DIR/.heroku/venv /app/.heroku/venv
+  # python expects to reside in /app, so set up symlinks
+  # we will not remove these later so subsequent buildpacks can still invoke it
+  ln -s $BUILD_DIR/.heroku/python /app/.heroku/python
+  ln -s $BUILD_DIR/.heroku/vendor /app/.heroku/vendor
+  ln -s $BUILD_DIR/.heroku/venv /app/.heroku/venv
+  # NOTE: /app/.heroku/src also exists, but is copied manually later.
 fi
 
 # Install Python.
@@ -208,8 +207,11 @@ set-default-env PYTHONPATH /app/
 # Install sane-default script for $WEB_CONCURRENCY and $FORWARDED_ALLOW_IPS.
 cp $ROOT_DIR/vendor/python.gunicorn.sh $GUNICORN_PROFILE_PATH
 
-# Deep copy the directory for -e pip installations
-deep-cp /app/.heroku/src $BUILD_DIR/.heroku/src
+# Symlink the directory for -e pip installations
+if [[ $BUILD_DIR != '/app' ]]; then
+  mv /app/.heroku/src $BUILD_DIR/.heroku
+  ln -s /app/.heroku/src $BUILD_DIR/.heroku/src
+fi
 
 # Experimental post_compile hook.
 bpwatch start post_compile
@@ -224,6 +226,7 @@ bpwatch start dump_cache
   rm -rf $CACHE_DIR/.heroku/python-stack
   rm -rf $CACHE_DIR/.heroku/vendor
   rm -rf $CACHE_DIR/.heroku/venv
+  rm -rf $CACHE_DIR/.heroku/src
 
   mkdir -p $CACHE_DIR/.heroku
   cp -R .heroku/python $CACHE_DIR/.heroku/
@@ -231,6 +234,7 @@ bpwatch start dump_cache
   cp -R .heroku/python-stack $CACHE_DIR/.heroku/ &> /dev/null || true
   cp -R .heroku/vendor $CACHE_DIR/.heroku/ &> /dev/null || true
   cp -R .heroku/venv $CACHE_DIR/.heroku/ &> /dev/null || true
+  cp -R .heroku/src $CACHE_DIR/.heroku/ &> /dev/null || true
 
 bpwatch stop dump_cache
 

bin/steps/pip-install

@@ -4,10 +4,8 @@ puts-cmd "pip install -r requirements.txt"
 [ ! "$FRESH_PYTHON" ] && bpwatch start pip_install
 [ "$FRESH_PYTHON" ] && bpwatch start pip_install_first
 
-
-
 set +e
-/app/.heroku/python/bin/pip install -r requirements.txt --exists-action=w --src=/app/.heroku/src --disable-pip-version-check --no-cache-dir 2>&1 | tee $WARNINGS_LOG | cleanup | indent
+/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
 
@@ -22,6 +20,12 @@ fi
 cp requirements.txt .heroku/python/requirements-declared.txt
 /app/.heroku/python/bin/pip freeze --disable-pip-version-check > .heroku/python/requirements-installed.txt
 
+# Replace egg-links with new paths for /app.
+# find .heroku/python/lib/python*/site-packages/ -name "*.egg-link" -print0 | xargs -0 cat
+
+find .heroku/python/lib/python*/site-packages/ -name "*.egg-link" -print0 | xargs -r -0 -n 1 sed -i -e "s#$(pwd)/#./app/#"
+find .heroku/python/lib/python*/site-packages/ -name "easy-install.pth" -print0 | xargs -r -0 -n 1 sed -i -e "s#$(pwd)/#/app/#"
+
 [ ! "$FRESH_PYTHON" ] && bpwatch stop pip_install
 [ "$FRESH_PYTHON" ] && bpwatch stop pip_install_first