echo Hello World
echo "Hello World"
ShellCheck found multiple unquoted spaces between words passed to
echo. Due to the way arguments are interpreted and passed in the shell, these will collapse into a single space:
$ echo Hello World Hello World
If you want to output multiple spaces, such as when creating a notice or banner, make sure the spaces are quoted, e.g. by adding (or extending) double quotes to include them:
$ echo "Hello World" Hello World
If you're aware of this behavior and didn't want multiple spaces to show up in the output, you can either remove the unnecessary spaces or ignore this issue.
ShellCheck is a static analysis tool for shell scripts. This page is part of its documentation.