Add cache of conda installation to Travis

.travis.yml

@@ -24,8 +24,11 @@ script:
   - tox
 after_success:
   - if [[ "$COVERAGE" == "true" ]]; then coveralls || echo "failed"; fi
+after_script:
+  - travis-cleanup
 cache:
   apt: true
   pip: true
   directories:
     - $HOME/.cache/pip
+    - $HOME/miniconda

tests/travis_install.sh

@@ -8,18 +8,25 @@
 #
 # THIS SCRIPT IS SUPPOSED TO BE AN EXAMPLE. MODIFY IT ACCORDING TO YOUR NEEDS!
 
-set -e
+set -e -x  # Exit on errors and debug mode
 
 if [[ "$DISTRIB" == "conda" ]]; then
     # Deactivate the travis-provided virtual environment and setup a
     # conda-based environment instead
     deactivate
 
-    # Use the miniconda installer for faster download / install of conda
-    # itself
-    wget http://repo.continuum.io/miniconda/Miniconda3-latest-Linux-x86_64.sh \
-        -O miniconda.sh
-    chmod +x miniconda.sh && ./miniconda.sh -b -p $HOME/miniconda
+    if [[ -f "$HOME/miniconda/bin" ]]; then
+        echo "Skip install conda"
+    else
+      rm -rf "$HOME/miniconda"
+      # ^  Caching creates empty dir that conflicts with conda installer
+
+      # Use the miniconda installer for faster download / install of conda
+      # itself
+      wget http://repo.continuum.io/miniconda/Miniconda3-latest-Linux-x86_64.sh \
+          -O miniconda.sh
+      chmod +x miniconda.sh && ./miniconda.sh -b -p $HOME/miniconda
+    fi
     export PATH=$HOME/miniconda/bin:$PATH
     conda update --yes conda
 
@@ -33,7 +40,20 @@ fi
 if [[ "$COVERAGE" == "true" ]]; then
     pip install coverage coveralls
 fi
+
 # for all
 pip install -U pip setuptools
 pip install sphinx
 pip install tox
+
+travis-cleanup() {
+  printf "Cleaning up environments ... "  # printf avoids new lines
+  if [[ "$DISTRIB" == "conda" ]]; then
+    # Force the env to be recreated next time, for build consistency
+    source deactivate
+    conda remove -n testenv --all --yes
+  fi
+  echo "DONE"
+}
+
+set +x