Improve conda_init script

Implement more robust method for extracting conda install
location from interactive subshells. Redo order of logic for
places to search. Add '-v' flag for printing debug info.

src/conda/conda_init.sh

@@ -4,74 +4,127 @@
 # non-interactive shell.
 # The script is what's placed in ~/.bashrc by 'conda init bash'; 
 # this doesn't get sourced by bash in non-interactive mode so we have to 
-# do it manually.
+# do it manually. See https://github.com/conda/conda/issues/7980 .
 
 # NOTE this has only been tested with conda 4.7.10 and later; I know earlier 
 # versions had things in different places.
 
-# Try to determine where conda is
-function find_conda {
-    _MDTF_CONDA_ROOT="$( conda info --base 2> /dev/null )"
-    if [[ $? -ne 0 || -z "$_MDTF_CONDA_ROOT" ]]; then
-        # see if env vars tell us anything
-        if [[ -n "$CONDA_EXE" ]]; then
-            _MDTF_CONDA_ROOT="$( cd "$(dirname "$CONDA_EXE")/.."; pwd -P )"
-        elif [[ -n "$_CONDA_ROOT" ]]; then
-            _MDTF_CONDA_ROOT="$_CONDA_ROOT"
-        else
-            _MDTF_CONDA_ROOT="" # failure
-        fi
-    fi
-}
-
 # parse aruments manually
-_MDTF_CONDA_ROOT=""
-_quiet=""
+_TEMP_CONDA_ROOT=""
+_TEMP_CONDA_EXE=""
+_v=1
 while (( "$#" )); do
     case "$1" in
+        -v)
+            _v=2 # verbose output for debugging
+            shift 1
+            ;;
         -q)
-            _quiet="0" # suppress output
+            _v=0 # suppress output
             shift 1
             ;;
-        -?*)
-            # passed the path to use on command line
-            _MDTF_CONDA_ROOT="$1"
+        ?*)
+            # Assume nonempty input is user-specified CONDA_ROOT
+            if [ ! -d "$1" ]; then
+                echo "ERROR: \"$1\" not a directory" 1>&2
+                exit 1
+            fi
+            _TEMP_CONDA_ROOT="$1"
             shift 1
             ;;
         *) # Default case: No more options, so break out of the loop.
             break
     esac
 done
 
-if [[ -z "$_MDTF_CONDA_ROOT" ]]; then
-    find_conda
+# if we got _TEMP_CONDA_ROOT from command line, see if that works
+if [ -d "$_TEMP_CONDA_ROOT" ]; then
+    # let command line value override pre-existing _CONDA_ROOT, in case user
+    # is specifying personal vs. site installation of conda
+    if [[ $_v -eq 2 && -d "$_CONDA_ROOT" ]]; then
+        echo "WARNING: overriding ${_CONDA_ROOT} with ${_TEMP_CONDA_ROOT}" 1>&2
+    fi
+    _CONDA_ROOT="$_TEMP_CONDA_ROOT"
+    if [[ $_v -eq 2 && -x "$CONDA_EXE" ]]; then
+        echo "WARNING: user supplied CONDA_ROOT so unsetting existing CONDA_EXE" 1>&2
+    fi
+    CONDA_EXE=""
+    if [ $_v -eq 2 ]; then echo "CONDA_ROOT set from command line"; fi
+fi
+# if not, maybe we were run from an interactive shell and inherited the info
+if [ ! -d "$_CONDA_ROOT" ]; then
+    if [ -x "$CONDA_EXE" ]; then
+        if [ $_v -eq 2 ]; then echo "CONDA_EXE set from environment"; fi
+        _TEMP_CONDA_ROOT="$( "$CONDA_EXE" info --base 2> /dev/null )"
+    else
+        _TEMP_CONDA_ROOT="$( conda info --base 2> /dev/null )"
+    fi
+    if [ -d "$_TEMP_CONDA_ROOT" ]; then
+        _CONDA_ROOT="$_TEMP_CONDA_ROOT"
+        if [ $_v -eq 2 ]; then echo "CONDA_ROOT set from environment"; fi
+    fi
 fi
-if [[ -z "$_MDTF_CONDA_ROOT" ]]; then
-    if [[ -z "$_quiet" ]]; then
-        echo "conda not found, sourcing ~/.bashrc"
+# if not, run user's shell in interactive mode. Subshell output could have 
+# arbitrary text output in it, since user's init scripts may be setting prompt
+# and generating output in any number of ways. We try to extract the paths by 
+# delimiting them with (hopefully uncommon) vertical tab characters (\v) and 
+# using awk to extract whatever text is found between those two field separators.
+if [ ! -d "$_CONDA_ROOT" ]; then
+    if [ $_v -eq 2 ]; then echo "Setting conda from $SHELL -i"; fi
+    _TEMP_CONDA_ROOT=$( "$SHELL" -i -c "_temp=\$( conda info --base ) && echo \"\v\${_temp}\v\"" | awk 'BEGIN { FS = "\v" } ; { print $2 }' )
+    if [ $_v -eq 2 ]; then echo "Received CONDA_ROOT=\"${_TEMP_CONDA_ROOT}\""; fi
+    if [[ -d "$_TEMP_CONDA_ROOT" ]]; then
+        _CONDA_ROOT="$_TEMP_CONDA_ROOT"
+        if [ $_v -eq 2 ]; then echo "Found CONDA_ROOT"; fi
     fi
-    if [[ -f "$HOME/.bashrc" ]]; then
-        source "$HOME/.bashrc"
+    _TEMP_CONDA_EXE="$( "$SHELL" -i -c "echo \"\v\${CONDA_EXE}\v\"" | awk 'BEGIN { FS = "\v" } ; { print $2 }' )"
+    if [ $_v -eq 2 ]; then echo "Received CONDA_EXE=\"${_TEMP_CONDA_EXE}\""; fi
+    if [[ ! -x "$CONDA_EXE" && -x "$_TEMP_CONDA_EXE" ]]; then
+        CONDA_EXE="$_TEMP_CONDA_EXE"
+        if [ $_v -eq 2 ]; then echo "Found CONDA_EXE"; fi
+    fi
+fi
+# found root but not exe
+if [[ -d "$_CONDA_ROOT" && ! -x "$CONDA_EXE" ]]; then
+    if [ $_v -eq 2 ]; then echo "Looking for conda executable in ${_CONDA_ROOT}"; fi
+    if [ -x "${_CONDA_ROOT}/bin/conda" ]; then
+        CONDA_EXE="${_CONDA_ROOT}/bin/conda"
+        if [ $_v -eq 2 ]; then echo "Found CONDA_EXE"; fi
+    elif [ -x "${_CONDA_ROOT}/condabin/conda" ]; then
+        CONDA_EXE="${_CONDA_ROOT}/condabin/conda"
+        if [ $_v -eq 2 ]; then echo "Found CONDA_EXE"; fi
     fi
-    find_conda
 fi
-if [[ -z "$_MDTF_CONDA_ROOT" ]]; then
-    echo "ERROR: still can't find conda"
+# found exe but not root
+if [[ -x "$CONDA_EXE" && ! -d "$_CONDA_ROOT" ]]; then
+    if [ $_v -eq 2 ]; then echo "Running $CONDA_EXE to find conda root"; fi
+    _TEMP_CONDA_ROOT="$( "$CONDA_EXE" info --base 2> /dev/null )"
+    if [ -d "$_TEMP_CONDA_ROOT" ]; then
+        _CONDA_ROOT="$_TEMP_CONDA_ROOT"
+        if [ $_v -eq 2 ]; then echo "Found CONDA_ROOT"; fi
+    fi
 fi
-export _CONDA_ROOT="$_MDTF_CONDA_ROOT"
-export CONDA_EXE="${_CONDA_ROOT}/bin/conda"
-export _CONDA_EXE="$CONDA_EXE"
-if [[ -x "$CONDA_EXE" ]]; then
-    if [[ -z "$_quiet" ]]; then
+
+if [[ -x "$CONDA_EXE" && -d "$_CONDA_ROOT" ]]; then
+    if [ $_v -ne 0 ]; then
+        # Conda env manager reads this output
         echo "_CONDA_EXE=${CONDA_EXE}"
         echo "_CONDA_ROOT=${_CONDA_ROOT}"
     fi
+    # in case these weren't exported already
+    export _CONDA_ROOT="$_CONDA_ROOT"
+    export CONDA_EXE="$CONDA_EXE"
 else
-    echo "ERROR: no conda executable at $CONDA_EXE"
+    if [ ! -d "$_CONDA_ROOT" ]; then
+        echo "ERROR: search for conda base dir failed (${_CONDA_ROOT})" 1>&2
+    fi
+    if [ ! -x "$CONDA_EXE" ]; then
+        echo "ERROR: search for conda executable failed (${CONDA_EXE})" 1>&2
+    fi
     exit 1
 fi
 
-# assume we've found conda, now run Anaconda's init script
+# finally run conda's init script
 __conda_setup="$( $CONDA_EXE 'shell.bash' 'hook' 2> /dev/null )"
 if [ $? -eq 0 ]; then
     eval "$__conda_setup"