Module dropin 

Drop-in style installation.

Some users (or their dotfiles managers — chezmoi, yadm, stow, oh-my-zsh custom/, etc.) keep their shell config split into a small main file plus a directory of numbered fragments that the main file sources in lexical order (e.g. ~/.zshenv.d/00-homebrew.zsh, 10-fnm.zsh, …).

When that convention is in use, appending an inline fenced block to the main rc file creates drift between the main file and the dotfiles source of truth. The drop-in install mode writes the same hook content into a single fragment file in the .d/ directory instead, leaving the main rc file untouched.

Detection is conservative: we require both that the .d/ directory exists AND that the main rc file references it from a non-comment line. That avoids treating an unused empty directory as opt-in.

Functions

detect

Detect whether the user’s rc file in home references the named drop-in directory and that directory exists. Returns the resolved directory path on success.

rc_references_dropin

True if any non-comment line in rc_contents mentions dropin_dir_name.

remove

Remove <dir>/<filename> if it exists. No-op otherwise.

write

Write content to <dir>/<filename>, creating dir if needed.