select.sh produce unneeded warnings when the only option is "-n"

[ebgssth@…]

$ python_select -n
/opt/local/bin/python_select: line 83: [: ==: unary operator expected
/opt/local/bin/python_select: line 83: [: ==: unary operator expected
/opt/local/bin/python_select: line 83: [: ==: unary operator expected
/opt/local/bin/python_select: line 83: [: ==: unary operator expected
version "" is invalid!

easy fix would be

-                 if [ ${1} == ${version} ]; then
+                if [ x${1} == x${version} ]; then

might be better to stop script when python_select called with -n only

[ebgssth@…]

attached a patch for this. also added -e option to sh so that any error causes script stop

[raimue@…]

This does not only affect python_select, but also gcc_select as both are using the general select.sh script. It was written by mww and resides in his user directory in svn, so I will reassign this issue to him.

[ebgssth@…]

Any update?

[raimue@…]

I tried to apply this patch today, but it did not work completely.

bash -e causes problems at the let command. As documented in help let in bash:

    If the last ARG evaluates to 0, let returns 1; 0 is returned
    otherwise.

It will always fail on this line using let with -e.

Committed the other parts of the patch in r39794 and r39795.