Port Homebrew::DevCmd::Cat

Library/Homebrew/dev-cmd/cat.rb

@@ -1,62 +1,65 @@
-# typed: true
+# typed: strict
 # frozen_string_literal: true
 
+require "abstract_command"
 require "cli/parser"
 
 module Homebrew
-  sig { returns(CLI::Parser) }
-  def self.cat_args
-    Homebrew::CLI::Parser.new do
-      description <<~EOS
-        Display the source of a <formula> or <cask>.
-      EOS
+  module DevCmd
+    class Cat < AbstractCommand
+      include FileUtils
 
-      switch "--formula", "--formulae",
-             description: "Treat all named arguments as formulae."
-      switch "--cask", "--casks",
-             description: "Treat all named arguments as casks."
+      cmd_args do
+        description <<~EOS
+          Display the source of a <formula> or <cask>.
+        EOS
 
-      conflicts "--formula", "--cask"
+        switch "--formula", "--formulae",
+               description: "Treat all named arguments as formulae."
+        switch "--cask", "--casks",
+               description: "Treat all named arguments as casks."
 
-      named_args [:formula, :cask], min: 1, without_api: true
-    end
-  end
+        conflicts "--formula", "--cask"
 
-  def self.cat
-    args = cat_args.parse
-
-    cd HOMEBREW_REPOSITORY do
-      pager = if Homebrew::EnvConfig.bat?
-        ENV["BAT_CONFIG_PATH"] = Homebrew::EnvConfig.bat_config_path
-        ENV["BAT_THEME"] = Homebrew::EnvConfig.bat_theme
-        ensure_formula_installed!(
-          "bat",
-          reason:           "displaying <formula>/<cask> source",
-          # The user might want to capture the output of `brew cat ...`
-          # Redirect stdout to stderr
-          output_to_stderr: true,
-        ).opt_bin/"bat"
-      else
-        "cat"
+        named_args [:formula, :cask], min: 1, without_api: true
       end
 
-      args.named.to_paths.each do |path|
-        next path if path.exist?
+      sig { override.void }
+      def run
+        cd HOMEBREW_REPOSITORY do
+          pager = if Homebrew::EnvConfig.bat?
+            ENV["BAT_CONFIG_PATH"] = Homebrew::EnvConfig.bat_config_path
+            ENV["BAT_THEME"] = Homebrew::EnvConfig.bat_theme
+            ensure_formula_installed!(
+              "bat",
+              reason:           "displaying <formula>/<cask> source",
+              # The user might want to capture the output of `brew cat ...`
+              # Redirect stdout to stderr
+              output_to_stderr: true,
+            ).opt_bin/"bat"
+          else
+            "cat"
+          end
 
-        path = path.basename(".rb") if args.cask?
+          args.named.to_paths.each do |path|
+            next path if path.exist?
 
-        ofail "#{path}'s source doesn't exist on disk."
+            path = path.basename(".rb") if args.cask?
+
+            ofail "#{path}'s source doesn't exist on disk."
+          end
+
+          if Homebrew.failed?
+            $stderr.puts "The name may be wrong, or the tap hasn't been tapped. Instead try:"
+            treat_as = "--cask " if args.cask?
+            treat_as = "--formula " if args.formula?
+            $stderr.puts "  brew info --github #{treat_as}#{args.named.join(" ")}"
+            return
+          end
+
+          safe_system pager, *args.named.to_paths
+        end
       end
-
-      if Homebrew.failed?
-        $stderr.puts "The name may be wrong, or the tap hasn't been tapped. Instead try:"
-        treat_as = "--cask " if args.cask?
-        treat_as = "--formula " if args.formula?
-        $stderr.puts "  brew info --github #{treat_as}#{args.named.join(" ")}"
-        return
-      end
-
-      safe_system pager, *args.named.to_paths
     end
   end
 end

Library/Homebrew/test/dev-cmd/cat_spec.rb

@@ -1,9 +1,10 @@
 # frozen_string_literal: true
 
 require "cmd/shared_examples/args_parse"
+require "dev-cmd/cat"
 
-RSpec.describe "brew cat" do
-  it_behaves_like "parseable arguments"
+RSpec.describe Homebrew::DevCmd::Cat do
+  it_behaves_like "parseable arguments", argv: ["foo"]
 
   it "prints the content of a given Formula", :integration_test do
     formula_file = setup_test_formula "testball"