[PATCH v2] edksetup.sh: Simplify SetupPython3 and SetupPython functions.

[rebecca@bsdio.com]

On Linux, "whereis" matches python3, python3.7, as well as
man pages, libs etc.  While on macOS it only matches the specified
name, and so misses python3.7. Improve this by looping over
potential version numbers and seeing if such a binary exists and
can be executed.

Signed-off-by: Rebecca Cran <rebecca@bsdio.com>
---
 edksetup.sh | 44 +++++++-------------------------------------
 1 file changed, 7 insertions(+), 37 deletions(-)

diff --git a/edksetup.sh b/edksetup.sh
index 06d2f041e6..5b90e55ed8 100755
--- a/edksetup.sh
+++ b/edksetup.sh
@@ -107,24 +107,10 @@ function SetupEnv()
 
 function SetupPython3()
 {
-  if [ $origin_version ];then
-    origin_version=
-  fi
-  for python in $(whereis python3)
-  do
-    python=$(echo $python | grep "[[:digit:]]$" || true)
-    python_version=${python##*python}
-    if [ -z "${python_version}" ] || (! command -v $python >/dev/null 2>&1);then
-      continue
-    fi
-    if [ -z $origin_version ];then
-      origin_version=$python_version
-      export PYTHON_COMMAND=$python
-      continue
-    fi
-      if [[ "$origin_version" < "$python_version" ]]; then
-      origin_version=$python_version
+  for ((pyver=15; pyver>=1; --pyver)); do
+    if python=$(command -v python3.$pyver); then
       export PYTHON_COMMAND=$python
+      break
     fi
   done
   return 0
@@ -146,27 +132,11 @@ function SetupPython()
     SetupPython3
   fi
 
-  if [ $PYTHON3_ENABLE ] && [ $PYTHON3_ENABLE != TRUE ]
-  then
-    if [ $origin_version ];then
-      origin_version=
-    fi
-    for python in $(whereis python2)
-    do
-      python=$(echo $python | grep "[[:digit:]]$" || true)
-      python_version=${python##*python}
-      if [ -z "${python_version}" ] || (! command -v $python >/dev/null 2>&1);then
-        continue
-      fi
-      if [ -z $origin_version ]
-      then
-        origin_version=$python_version
-        export PYTHON_COMMAND=$python
-        continue
-      fi
-      if [[ "$origin_version" < "$python_version" ]]; then
-        origin_version=$python_version
+  if [ -n "$PYTHON3_ENABLE" ] && [ "$PYTHON3_ENABLE" != "TRUE" ]; then
+    for ((pyver=10; pyver>=1; --pyver)); do
+      if python=$(command -v python2.$pyver); then
         export PYTHON_COMMAND=$python
+        break
       fi
     done
     return 0
-- 
2.22.0