ENH: add plugin for Anaconda Python environments

plugins/anaconda/anaconda.plugin.zsh

@@ -0,0 +1,79 @@
+if [ -n "${ANACONDA_BASE+x}" ]; then
+  if [[ ! $DISABLE_ANACONDA_CD -eq 1 ]]; then
+    # Automatically activate Git projects's Anaconda Python environment based on the
+    # directory name of the project. Anaconda environment name can be overridden
+    # by placing a .aenv file in the project root with an environment name or full path in it
+    function anaconda_cwd {
+        if [ ! $ANACONDA_CWD ]; then
+            ANACONDA_CWD=1
+            # Check if this is a Git repo
+            PROJECT_ROOT=`git rev-parse --show-toplevel 2> /dev/null`
+            if (( $? != 0 )); then
+                PROJECT_ROOT="."
+            fi
+            # Check for environment name override
+            if [[ -f "$PROJECT_ROOT/.aenv" ]]; then
+                AENV_HINT=`cat "$PROJECT_ROOT/.aenv"`
+		if [[ -d "$ANACONDA_BASE/envs/$AENV_HINT" ]]; then
+                   AENV_NAME=$AENV_HINT
+		   AENV_PATH="$ANACONDA_BASE/envs/$AENV_HINT"
+		elif [[ -d "$AENV_HINT" ]]; then
+                   AENV_NAME=$AENV_HINT
+		   AENV_PATH=`readlink -f $AENV_HINT`
+		fi
+            elif [[ "$PROJECT_ROOT" != "." && -d "$ANACONDA_BASE/envs/`basename \"$PROJECT_ROOT\"`" ]]; then
+		AENV_PATH="$ANACONDA_BASE/envs/`basename \"$PROJECT_ROOT\"`"
+                AENV_NAME=$AENV_PATH
+            else
+                AENV_NAME=""
+            fi
+            if [[ "$AENV_NAME" != "" ]]; then
+                # Activate the environment only if it is not already active
+                if [[ `readlink -f "$CONDA_DEFAULT_ENV"` != "$AENV_PATH" ]]; then
+		    ANACONDA_SAVE_PROMPT=$PROMPT
+                    source $AENV_PATH/bin/activate "$AENV_NAME" && export CD_ANACONDA_ENV="$AENV_PATH"
+		    PROMPT=$ANACONDA_SAVE_PROMPT
+		    # TODO: test with named Anaconda environments
+		    # TODO: work-around conda deactivate bug regarding paths
+		    # TODO: overload builtin 'cd' function
+		    # see http://virtualenvwrapper.readthedocs.org/en/latest/tips.html#changing-the-default-behavior-of-cd
+		    # currently not working in ZSH ...
+                    ## cd () {
+                    ##     if (( $# == 0 ))
+                    ##     then
+                    ##         builtin cd $VIRTUAL_ENV
+                    ##     else
+                    ##         builtin cd "$@"
+                    ##     fi
+                    ## }
+		    # see http://virtualenvwrapper.readthedocs.org/en/latest/tips.html#updating-cached-path-entries
+		    rehash
+                fi
+            elif [ $CD_ANACONDA_ENV ]; then
+                # We've just left the repo, deactivate the environment
+                # Note: this only happens if the virtualenv was activated automatically
+                source $AENV_PATH/bin/deactivate && unset CD_ANACONDA_ENV
+		PROMPT=$ANACONDA_SAVE_PROMPT
+		# see http://virtualenvwrapper.readthedocs.org/en/latest/tips.html#updating-cached-path-entries
+		rehash
+            fi
+            unset PROJECT_ROOT
+            unset ANACONDA_CWD
+            unset AENV_BASE
+        fi
+    }
+
+    # Append anaconda_cwd to the chpwd_functions array, so it will be called on cd
+    # http://zsh.sourceforge.net/Doc/Release/Functions.html
+    # TODO: replace with 'add-zsh-hook chpwd anaconda_cwd' when oh-my-zsh min version is raised above 4.3.4
+    if (( ${+chpwd_functions} )); then
+        if (( $chpwd_functions[(I)anaconda_cwd] == 0 )); then
+            set -A chpwd_functions $chpwd_functions anaconda_cwd
+        fi
+    else
+        set -A chpwd_functions anaconda_cwd
+    fi
+  fi
+else
+  print "zsh anaconda plugin: Cannot find Anaconda installation. Please set the environment variable \`ANACONDA_BASE\`."
+fi