Improved utilization of PROMPT_COMMAND

README.md

@@ -1,16 +1,26 @@
 # conda-auto-env
 
-Automatically activate a conda environment when entering a folder with an environment.yml file.
+(Semi-)Automatically activate a conda environment when entering a folder with an `environment.yml` file.
 
-If the environment doesn't exist, conda-auto-env creates it and activates it for you.
+If the environment doesn't exist, `conda-auto-env` creates it and activates it for you.
 
 This functionality was inspired by [conda auto activate](https://github.com/sotte/conda_auto_activate), [virtualenv auto activate](https://gist.github.com/garyjohnson/394c58e22a2adfa103e2) and [autoenv](https://github.com/kennethreitz/autoenv).
 
 ## Install
 
 To install add this line to your .bashrc or .bash-profile:
 
-       source /path/to/conda_auto_env.sh
+```bash
+source /path/to/conda_auto_env.sh
+```
+
+If you also want this script to be ran automatically, whenever you enter a directory add also the following:
+
+```bash
+export PROMPT_COMMAND="conda_auto_env;$PROMPT_COMMAND"
+```
+
+Otherwise, whenever in a directory containing `environment.yml`, you can execute `conda_auto_env`.
 
 ### Remote environments
 

conda_auto_env.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 
-# conda-auto-env automatically activates a conda environment when
-# entering a folder with an environment.yml file.
+# conda-auto-env is a utility to activate a conda environment in a folder
+# with an environment.yml file or based on the current dir's name.
 #
 # If the environment doesn't exist, conda-auto-env creates it and
 # activates it for you.
@@ -11,24 +11,64 @@
 #       source /path/to/conda_auto_env.sh
 #
 
+DEFAULT_PY_VER=3.6
+
 function conda_auto_env() {
+
+  function activate_env() {
+    conda activate $1
+    if [[ $? -eq 0 ]]; then
+      echo "${1} activated successfully"
+    else
+      echo "Failed to activate ${1}"
+      return 1
+    fi
+  }
+
+  function deactivate_env() {
+    conda deactivate
+    if [[ $? -eq 0 ]]; then
+      echo "Deactivated successfully"
+    else
+      echo "Failed to deactivate"
+      return 1
+    fi
+  }
+
+  # Determine ENV's name; eitehr from environment.yml
+  # or based on current dir name
   if [ -e "environment.yml" ]; then
-    # echo "environment.yml file found"
+    echo "Found environment.yml"
     ENV=$(head -n 1 environment.yml | cut -f2 -d ' ')
-    # Check if you are already in the environment
-    if [[ $PATH != *$ENV* ]]; then
-      # Check if the environment exists
-      source activate $ENV
-      if [ $? -eq 0 ]; then
-        :
-      else
-        # Create the environment and activate
-        echo "Conda env '$ENV' doesn't exist."
+  else
+    echo "No environment.yml found. Reverting to current dir"
+    ENV=${PWD##*/}
+  fi
+
+  echo "Processing the environment: ${ENV}"
+
+  if [ $ENV = $CONDA_DEFAULT_ENV ]; then
+    # ENV is already activated. Deactivate
+    deactivate_env
+  elif [[ $PATH != *$ENV* ]]; then
+    # ENV is not activated. Trying to activate
+    activate_env $ENV
+    if [ $? -ne 0 ]; then
+      # Failed to activate. Creating environment
+      echo "Conda env '$ENV' doesn't exist."
+      if [[ -e "environment.yml" ]]; then
+        echo "Creating ${ENV} based on environment.yml"
         conda env create -q
-        source activate $ENV
+      else
+        echo "Creating ${ENV} with default settings"
+        conda create -n ${ENV} python=${DEFAULT_PY_VER}
       fi
+      activate_env $ENV
     fi
   fi
-}
 
-export PROMPT_COMMAND=conda_auto_env
+  # Make sure utility functions are local
+  unset -f activate_env
+  unset -f deactivate_env
+  unset ENV
+}