centralize the logic of handling homebrew- in Tap.fetch

Closes Homebrew/homebrew#46537.

Signed-off-by: Xu Cheng <xucheng@me.com>

Library/Homebrew/cmd/info.rb

@@ -69,7 +69,7 @@ module Homebrew
   def github_info(f)
     if f.tap?
       user, repo = f.tap.split("/", 2)
-      tap = Tap.fetch user, repo.gsub(/^homebrew-/, "")
+      tap = Tap.fetch user, repo
       if remote = tap.remote
         path = f.path.relative_path_from(tap.path)
         github_remote_path(remote, path)

Library/Homebrew/cmd/install.rb

@@ -16,9 +16,7 @@ module Homebrew
     ARGV.named.each do |name|
       if !File.exist?(name) && (name !~ HOMEBREW_CORE_FORMULA_REGEX) \
               && (name =~ HOMEBREW_TAP_FORMULA_REGEX || name =~ HOMEBREW_CASK_TAP_FORMULA_REGEX)
-        user = $1
-        repo = $2.sub(/^homebrew-/, "")
-        tap = Tap.fetch(user, repo)
+        tap = Tap.fetch($1, $2)
         tap.install unless tap.installed?
       end
     end unless ARGV.force?

Library/Homebrew/cmd/update.rb

@@ -403,10 +403,8 @@ class Report
     fetch(:D, []).each do |path|
       case path.to_s
       when HOMEBREW_TAP_PATH_REGEX
-        user = $1
-        repo = $2.sub("homebrew-", "")
         oldname = path.basename(".rb").to_s
-        next unless newname = Tap.fetch(user, repo).formula_renames[oldname]
+        next unless newname = Tap.fetch($1, $2).formula_renames[oldname]
       else
         oldname = path.basename(".rb").to_s
         next unless newname = FORMULA_RENAMES[oldname]
@@ -427,7 +425,7 @@ class Report
   def select_formula(key)
     fetch(key, []).map do |path, newpath|
       if path.to_s =~ HOMEBREW_TAP_PATH_REGEX
-        tap = "#{$1}/#{$2.sub("homebrew-", "")}"
+        tap = Tap.fetch($1, $2)
         if newpath
           ["#{tap}/#{path.basename(".rb")}", "#{tap}/#{newpath.basename(".rb")}"]
         else

Library/Homebrew/exceptions.rb

@@ -76,7 +76,7 @@ class TapFormulaAmbiguityError < RuntimeError
     @paths = paths
     @formulae = paths.map do |path|
       path.to_s =~ HOMEBREW_TAP_PATH_REGEX
-      "#{$1}/#{$2.sub("homebrew-", "")}/#{path.basename(".rb")}"
+      "#{Tap.fetch($1, $2)}/#{path.basename(".rb")}"
     end
 
     super <<-EOS.undent

Library/Homebrew/formula.rb

@@ -134,7 +134,7 @@ class Formula
     @revision = self.class.revision || 0
 
     if path.to_s =~ HOMEBREW_TAP_PATH_REGEX
-      @full_name = "#{$1}/#{$2.gsub(/^homebrew-/, "")}/#{name}"
+      @full_name = "#{Tap.fetch($1, $2)}/#{name}"
     else
       @full_name = name
     end
@@ -296,7 +296,7 @@ class Formula
       end
     elsif tap?
       user, repo = tap.split("/")
-      formula_renames = Tap.fetch(user, repo.sub("homebrew-", "")).formula_renames
+      formula_renames = Tap.fetch(user, repo).formula_renames
       if formula_renames.value?(name)
         formula_renames.to_a.rassoc(name).first
       end
@@ -309,7 +309,7 @@ class Formula
       Formula.core_alias_reverse_table[name] || []
     elsif tap?
       user, repo = tap.split("/")
-      Tap.fetch(user, repo.sub("homebrew-", "")).alias_reverse_table[full_name] || []
+      Tap.fetch(user, repo).alias_reverse_table[full_name] || []
     else
       []
     end

Library/Homebrew/formulary.rb

@@ -145,7 +145,7 @@ class Formulary
 
     def initialize(tapped_name)
       user, repo, name = tapped_name.split("/", 3).map(&:downcase)
-      @tap = Tap.fetch user, repo.sub(/^homebrew-/, "")
+      @tap = Tap.fetch user, repo
       name = @tap.formula_renames.fetch(name, name)
       path = @tap.formula_files.detect { |file| file.basename(".rb").to_s == name }
 

Library/Homebrew/migrator.rb

@@ -31,9 +31,7 @@ class Migrator
       msg = if tap == "Homebrew/homebrew"
         "Please try to use #{formula.oldname} to refer the formula.\n"
       elsif tap
-        user, repo = tap.split("/")
-        repo.sub!("homebrew-", "")
-        "Please try to use fully-qualified #{user}/#{repo}/#{formula.oldname} to refer the formula.\n"
+        "Please try to use fully-qualified #{Tap.fetch(*tap.split("/"))}/#{formula.oldname} to refer the formula.\n"
       end
 
       super <<-EOS.undent

Library/Homebrew/tap.rb

@@ -17,6 +17,9 @@ class Tap
   end
 
   def self.fetch(user, repo)
+    # we special case homebrew so users don't have to shift in a terminal
+    user = "Homebrew" if user == "homebrew"
+    repo = repo.strip_prefix "homebrew-"
     cache_key = "#{user}/#{repo}".downcase
     CACHE.fetch(cache_key) { |key| CACHE[key] = Tap.new(user, repo) }
   end
@@ -39,9 +42,9 @@ class Tap
   # e.g. `/usr/local/Library/Taps/user/homebrew-repo`
   attr_reader :path
 
+  # @private
   def initialize(user, repo)
-    # we special case homebrew so users don't have to shift in a terminal
-    @user = user == "homebrew" ? "Homebrew" : user
+    @user = user
     @repo = repo
     @name = "#{@user}/#{@repo}".downcase
     @path = TAP_DIRECTORY/"#{@user}/homebrew-#{@repo}".downcase
@@ -268,7 +271,7 @@ class Tap
 
     TAP_DIRECTORY.subdirs.each do |user|
       user.subdirs.each do |repo|
-        yield fetch(user.basename.to_s, repo.basename.to_s.sub("homebrew-", ""))
+        yield fetch(user.basename.to_s, repo.basename.to_s)
       end
     end
   end