Uncle Bob On Videos

For those of you who are even later than me: Uncle Bob, famous for his Clean Code book has produced a series of one hour videos which cover the topics of the book - but in a very funny and at the same time educational way: Clean Code Videos

Bash syntax check

When automating your administrative tasks also shell scripts are checked in to a version control system. The built-in command line argument -n allows a syntax check of the shell script without executing it:

$ bash -n myScript.sh
$ echo $?
0

If the syntax check is successful nothing is displayed and the exit code is 0. However, if there is an error (like in the following case a missing parenthesis) an error message is printed and the exit code is 2:

$ bash -n myScript.sh
./myScript.sh: line 23: syntax error: unexpected end of file
$ echo $?
2

When checking your scripts in that way inside your continuous delivery pipeline it is easy to spot simple type errors.