Shellcheck's source directive for SC1090 should support either $HOME or ~tilde-expansion

[ELLIOTTCABLE]

For bugs

• Rule Id (if any, e.g. SC1000): SC1090
• My shellcheck version (shellcheck --version or "online"): 0.9.0
• The rule's wiki page does not already cover this (e.g. https://shellcheck.net/wiki/SC2086)
• I tried on https://www.shellcheck.net/ and verified that this is still a problem on the latest commit

Here's a snippet or screenshot that shows the problem:

mise_plugin_path="$HOME/.zsh/modules/wintermi/zsh-mise/zsh-mise.plugin.zsh"
if [ -f "$mise_plugin_path" ]; then
   # shellcheck source=~/.zsh/modules/wintermi/zsh-mise/zsh-mise.plugin.zsh
   . "$mise_plugin_path"

   debug_path_dump 'after zsh-mise.plugin.zsh'
fi

Here's what shellcheck currently says:

In Dotfiles/shenv line 267:
      . "$mise_plugin_path"
        ^-----------------^ SC1090 (warning): ShellCheck can't follow non-constant source. Use a directive to specify location.

---

This is related to #507, but smaller in scope: instead of supporting analysis of such paths in the source, I'd like to at least see them handled in explicit source directives, such as the above.

At the moment, if I use a tilde in the directive (source=~/.zsh/modules/wintermi/zsh-mise/zsh-mise.plugin.zsh), I get SC1090, as if it didn't try to resolve it at all; and if I use an environment-variable (source=$HOME/.zsh/modules/wintermi/zsh-mise/zsh-mise.plugin.zsh), I get told it can't be found:

In Dotfiles/shenv line 267:
      . "$mise_plugin_path"
        ^-----------------^ SC1091 (info): Not following: $HOME/.zsh/modules/wintermi/zsh-mise/zsh-mise.plugin.zsh: openBinaryFile: does not exist (No such file or directory)

[brother]

See also #2710

[ELLIOTTCABLE]

Oh my god, and I even commented on it last fall. jfc. Closing, it's a duplicate.