search: Add descriptions to option declarations

Library/Homebrew/cmd/search.rb

@@ -41,20 +41,38 @@ module Homebrew
     },
   }.freeze
 
-  def search(argv = ARGV)
-    CLI::Parser.parse(argv) do
-      switch "--desc"
+  def search_args
+    Homebrew::CLI::Parser.new do
+      usage_banner <<~EOS
+        `search`, `-S` [<options>] (<text>|`/`<text>`/`)
+
+         Perform a substring search of cask tokens and formula names for <text>. If <text>
+         is surrounded with slashes, then it is interpreted as a regular expression.
+         The search for <text> is extended online to `homebrew/core` and `homebrew/cask`.
+
+         If no <text> is passed, display all locally available formulae (including tapped ones).
+         No online search is performed.
+      EOS
+      switch "--casks",
+        description: "Display all locally available casks (including tapped ones). "\
+                     "No online search is performed."
+      switch "--desc",
+        description: "search formulae with a description matching <text> and casks with "\
+                     "a name matching <text>."
 
       package_manager_switches = PACKAGE_MANAGERS.keys.map { |name| "--#{name}" }
-
       package_manager_switches.each do |s|
-        switch s
+        switch s,
+          description: "Search for <text> in the given package manager's list."
       end
-
-      switch "--casks"
-
+      switch :verbose
+      switch :debug
       conflicts(*package_manager_switches)
     end
+  end
+
+  def search
+    search_args.parse
 
     if package_manager = PACKAGE_MANAGERS.find { |name,| args[:"#{name}?"] }
       _, url = package_manager