Vim indentation of a bash script seems broken after a pipe

Question

Vim builtin indentation seems to get confused with the following script. I cannot get Vim to indent properly the while-loop after the pipe.

#!/bin/bash

while true
do
    # while loop is indented correctly
    while read line
    do
        echo $line
    done < myfile

    # while loop after a pipe is NOT indented correctly despite gg=G
    cat myfile | while read line
do
    echo $line
done
done

Running gg=G does not fix the indentation. Any ideas?

Answer 1

You can't get what you want in this case without writing your own indent script or breaking up the lines like in Nobe4's answer. Take a look at GetShIndent() in $VIMRUNTIME/indent/sh.vim

It looks for the previous non-blank line that starts with while and increases the indent level. However, it checks if the current line starts with do to decrease the indent level. This is how it sets the correct indent if you use the inline while ; do variant. In your case, it finds the do on the current line but not the while on the previous line, so it drops the indent level lower than you expected.

Answer 2

I made the indentation works by splitting the cat/while like so:

while true
do
    ...

    cat myfile |
    while read line
    do
        echo $line
    done
done