Deprecate apr requirement.

It's not used on enough configurations now that there's little point in
keeping it around. See e.g. `:autoconf` for prior art.

Library/Homebrew/compat/dependency_collector.rb

@@ -13,6 +13,10 @@ class DependencyCollector
     when :cairo, :fontconfig, :freetype, :libpng, :pixman
       output_deprecation(spec, tags)
       Dependency.new(spec.to_s, tags)
+    when :apr
+      # TODO: reenable in future when we've fixed a few of the audits.
+      # output_deprecation(spec, tags, "apr-util")
+      Dependency.new("apr-util", tags)
     when :libltdl
       tags << :run
       output_deprecation("libtool", tags)
@@ -27,13 +31,13 @@ class DependencyCollector
     Dependency.new(spec.to_s, tags)
   end
 
-  def output_deprecation(dependency, tags)
+  def output_deprecation(dependency, tags, new_dependency = dependency)
     tags_string = if tags.length > 1
       " => [:#{tags.join ", :"}]"
     elsif tags.length == 1
       " => :#{tags.first}"
     end
     odeprecated "'depends_on :#{dependency}'",
-                "'depends_on \"#{dependency}\"#{tags_string}'"
+                "'depends_on \"#{new_dependency}\"#{tags_string}'"
   end
 end

Library/Homebrew/compat/requirements.rb

@@ -8,7 +8,6 @@ GPGRequirement             = GPG2Requirement
 TeXDependency              = TeXRequirement
 MercurialDependency        = MercurialRequirement
 GitDependency              = GitRequirement
-AprDependency              = AprRequirement
 FortranDependency          = FortranRequirement
 JavaDependency             = JavaRequirement
 LanguageModuleDependency   = LanguageModuleRequirement

Library/Homebrew/dependency_collector.rb

@@ -114,7 +114,6 @@ class DependencyCollector
     when :perl       then PerlRequirement.new(tags)
     when :tuntap     then TuntapRequirement.new(tags)
     when :ant        then ant_dep(spec, tags)
-    when :apr        then AprRequirement.new(tags)
     when :emacs      then EmacsRequirement.new(tags)
     # Tiger's ld is too old to properly link some software
     when :ld64       then LD64Dependency.new if MacOS.version < :leopard

Library/Homebrew/dev-cmd/audit.rb

@@ -811,6 +811,10 @@ class FormulaAuditor
       problem ":#{$1} is deprecated. Usage should be \"#{$1}\""
     end
 
+    if line =~ /depends_on :apr/
+      problem ":apr is deprecated. Usage should be \"apr-util\""
+    end
+
     # Commented-out depends_on
     problem "Commented-out dep #{$1}" if line =~ /#\s*depends_on\s+(.+)\s*$/
 

Library/Homebrew/requirements.rb

 require "requirement"
-require "requirements/apr_requirement"
 require "requirements/fortran_requirement"
 require "requirements/gpg2_requirement"
 require "requirements/language_module_requirement"

Library/Homebrew/requirements/apr_requirement.rb

-require "requirement"
-
-class AprRequirement < Requirement
-  fatal true
-  default_formula "apr-util"
-
-  # APR shipped in Tiger is too old, but Leopard+ is usable.
-  # The *-config scripts were removed in Sierra, which is widely breaking.
-  satisfy(build_env: false) do
-    next false if MacOS.version <= :leopard
-    next false if MacOS.version >= :sierra
-    MacOS::CLT.installed? || Formula["apr-util"].installed?
-  end
-
-  env do
-    next if MacOS.version <= :leopard
-    next if MacOS.version >= :sierra
-    next if MacOS::CLT.installed?
-    ENV.prepend_path "PATH", Formula["apr-util"].opt_bin
-    ENV.prepend_path "PATH", Formula["apr"].opt_bin
-    ENV.prepend_path "PKG_CONFIG_PATH", "#{Formula["apr"].opt_libexec}/lib/pkgconfig"
-    ENV.prepend_path "PKG_CONFIG_PATH", "#{Formula["apr-util"].opt_libexec}/lib/pkgconfig"
-  end
-
-  def to_dependency
-    super.extend Module.new {
-      def tags
-        super - [:build]
-      end
-    }
-  end
-end