Merge pull request #18524 from HeroCC/shellenv-fpath

shellenv: Add zsh site-functions to `fpath`

Library/Homebrew/cmd/shellenv.sh

@@ -81,6 +81,10 @@ homebrew-shellenv() {
       echo "export HOMEBREW_PREFIX=\"${HOMEBREW_PREFIX}\";"
       echo "export HOMEBREW_CELLAR=\"${HOMEBREW_CELLAR}\";"
       echo "export HOMEBREW_REPOSITORY=\"${HOMEBREW_REPOSITORY}\";"
+      if [[ "${HOMEBREW_SHELL_NAME}" == "zsh" ]] || [[ "${HOMEBREW_SHELL_NAME}" == "-zsh" ]]
+      then
+        echo "fpath[1,0]=\"${HOMEBREW_PREFIX}/share/zsh/site-functions\";"
+      fi
       if [[ -n "${PATH_HELPER_ROOT}" ]]
       then
         PATH_HELPER_ROOT="${PATH_HELPER_ROOT}" PATH="${HOMEBREW_PATH}" /usr/libexec/path_helper -s

docs/Shell-Completion.md

@@ -34,23 +34,14 @@ If you are using Homebrew's `bash` as your shell (i.e. `bash` >= v4) you should
 
 ## Configuring Completions in `zsh`
 
-To make Homebrew's completions available in `zsh`, you must insert the Homebrew-managed `zsh/site-functions` path into your `FPATH` before initialising `zsh`'s completion facility. Add the following to your `~/.zshrc`:
+To make Homebrew's completions available in `zsh`, the Homebrew-managed `zsh/site-functions` path needs to be inserted into `FPATH` before initialising `zsh`'s completion facility. This is done by `brew shellenv`, so if you followed the post-Homebrew installation steps, `eval "$(brew shellenv)"` should be in your `~/.zprofile` (on macOS) or `~/.zshrc` (on Linux). All you need is add the following to your `~/.zshrc` if it's not already there, and, if you're on Linux, make sure it's placed after `eval "$(brew shellenv)"`:
 
 ```sh
-if type brew &>/dev/null
-then
-  FPATH="$(brew --prefix)/share/zsh/site-functions:${FPATH}"
-
-  autoload -Uz compinit
-  compinit
-fi
+autoload -Uz compinit
+compinit
 ```
 
-This must be done before `compinit` is called. Note that if you are using Oh My Zsh, it will call `compinit` for you when you source `oh-my-zsh.sh`. In this case, instead of the above, add the following line to your `~/.zshrc`, before you source `oh-my-zsh.sh`:
-
-```sh
-FPATH="$(brew --prefix)/share/zsh/site-functions:${FPATH}"
-```
+Note that if you are using Oh My Zsh, it will call `compinit` for you when you source `oh-my-zsh.sh`. In this case, make sure `eval "$(brew shellenv)"` is called before sourcing `oh-my-zsh.sh` if you're on Linux, and you should be all set without any additional configuration.
 
 You may also need to forcibly rebuild `zcompdump`: