tap: default to full clones.

This makes `Tap` consistent with what the installer is doing.

Generally shallow clones get slower and slower (and more and more
pointless) the more they are fetched so don't make sense for our
use-case.

Keep the option around anyway because it's useful for integration tests.

Library/Homebrew/cmd/tap.rb

@@ -60,7 +60,8 @@ module Homebrew
                     quiet:             args.quieter?
       rescue TapRemoteMismatchError => e
         odie e
-      rescue TapAlreadyTappedError, TapAlreadyUnshallowError # rubocop:disable Lint/SuppressedException
+      rescue TapAlreadyTappedError
+        nil
       end
     end
   end

Library/Homebrew/exceptions.rb

@@ -258,18 +258,6 @@ class TapAlreadyTappedError < RuntimeError
   end
 end
 
-class TapAlreadyUnshallowError < RuntimeError
-  attr_reader :name
-
-  def initialize(name)
-    @name = name
-
-    super <<~EOS
-      Tap #{name} already a full clone.
-    EOS
-  end
-end
-
 class TapPinStatusError < RuntimeError
   attr_reader :name, :pinned
 

Library/Homebrew/tap.rb

@@ -233,7 +233,7 @@ class Tap
   def install(options = {})
     require "descriptions"
 
-    full_clone = options.fetch(:full_clone, false)
+    full_clone = options.fetch(:full_clone, true)
     quiet = options.fetch(:quiet, false)
     requested_remote = options[:clone_target] || default_remote
     # if :force_auto_update is unset, use nil, meaning "no change"
@@ -245,9 +245,12 @@ class Tap
       odie "#{name} was moved. Tap homebrew/cask-#{repo} instead."
     end
 
-    if installed? && force_auto_update.nil?
-      raise TapAlreadyTappedError, name unless full_clone
-      raise TapAlreadyUnshallowError, name unless shallow?
+    if installed?
+      if options[:clone_target] && requested_remote != remote
+        raise TapRemoteMismatchError.new(name, @remote, requested_remote)
+      end
+
+      raise TapAlreadyTappedError, name if force_auto_update.nil?
     end
 
     # ensure git is installed
@@ -259,10 +262,6 @@ class Tap
         return if !full_clone || !shallow?
       end
 
-      if options[:clone_target] && requested_remote != remote
-        raise TapRemoteMismatchError.new(name, @remote, requested_remote)
-      end
-
       ohai "Unshallowing #{name}" unless quiet
       args = %w[fetch --unshallow]
       args << "-q" if quiet

Library/Homebrew/test/tap_spec.rb

@@ -207,7 +207,6 @@ describe Tap do
     it "raises an error when the remote doesn't match" do
       setup_git_repo
       already_tapped_tap = described_class.new("Homebrew", "foo")
-      touch subject.path/".git/shallow"
       expect(already_tapped_tap).to be_installed
       wrong_remote = "#{subject.remote}-oops"
       expect {
@@ -215,12 +214,6 @@ describe Tap do
       }.to raise_error(TapRemoteMismatchError)
     end
 
-    it "raises an error when the Tap is already unshallow" do
-      setup_git_repo
-      already_tapped_tap = described_class.new("Homebrew", "foo")
-      expect { already_tapped_tap.install full_clone: true }.to raise_error(TapAlreadyUnshallowError)
-    end
-
     describe "force_auto_update" do
       before do
         setup_git_repo