Port brew --repository to Bash

Library/Homebrew/cmd/--repository.sh

@@ -0,0 +1,44 @@
+#:  * `--repository`, `--repo` [<tap> ...]
+#:
+#:  Display where Homebrew's Git repository is located.
+#:
+#:  If <user>`/`<repo> are provided, display where tap <user>`/`<repo>'s directory is located.
+
+# HOMEBREW_REPOSITORY, HOMEBREW_LIBRARY are set by brew.sh
+# shellcheck disable=SC2154
+
+tap_path() {
+  local tap="$1"
+  local user
+  local repo
+  local part
+
+  user="$(echo "${tap%%/*}" | tr '[:upper:]' '[:lower:]')"
+  repo="$(echo "${tap#*/}" | tr '[:upper:]' '[:lower:]')"
+
+  for part in "${user}" "${repo}"
+  do
+    if [[ -z "${part}" || "${part}" == *"/"* ]]
+    then
+      odie "Invalid tap name: ${tap}"
+    fi
+  done
+
+  repo="${repo#(home|linux)brew-}"
+  echo "${HOMEBREW_LIBRARY}/Taps/${user}/homebrew-${repo}"
+}
+
+homebrew---repository() {
+  local tap
+
+  if [[ "$#" -eq 0 ]]
+  then
+    echo "${HOMEBREW_REPOSITORY}"
+    return
+  fi
+
+  for tap in "$@"
+  do
+    tap_path "${tap}"
+  done
+}

Library/Homebrew/test/cmd/--repository_spec.rb

@@ -1,11 +1,6 @@
 # frozen_string_literal: true
 
-require "cmd/--repository"
-require "cmd/shared_examples/args_parse"
-
-RSpec.describe Homebrew::Cmd::Repository do
-  it_behaves_like "parseable arguments"
-
+RSpec.describe "brew --repository", type: :system do
   it "prints Homebrew's repository", :integration_test do
     expect { brew_sh "--repository" }
       .to output("#{ENV.fetch("HOMEBREW_REPOSITORY")}\n").to_stdout
@@ -14,8 +9,8 @@
   end
 
   it "prints a Tap's repository", :integration_test do
-    expect { brew "--repository", "foo/bar" }
-      .to output("#{HOMEBREW_LIBRARY}/Taps/foo/homebrew-bar\n").to_stdout
+    expect { brew_sh "--repository", "foo/bar" }
+      .to output("#{ENV.fetch("HOMEBREW_LIBRARY")}/Taps/foo/homebrew-bar\n").to_stdout
       .and not_to_output.to_stderr
       .and be_a_success
   end