audit: whitelist unstable versions already in core

also allow higher stable versions with the same version prefix

Library/Homebrew/dev-cmd/audit.rb

@@ -678,11 +678,47 @@ class FormulaAuditor
       end
     end
 
+    unstable_whitelist = %w[
+      aalib 1.4rc5
+      automysqlbackup 3.0-rc6
+      aview 1.3.0rc1
+      distcc 3.2rc1
+      elm-format 0.5.2-alpha
+      ftgl 2.1.3-rc5
+      hidapi 0.8.0-rc1
+      libcaca 0.99b19
+      premake 4.4-beta5
+      pwnat 0.3-beta
+      pxz 4.999.9
+      recode 3.7-beta2
+      speexdsp 1.2rc3
+      sqoop 1.4.6
+      tcptraceroute 1.5beta7
+      testssl 2.8rc3
+      tiny-fugue 5.0b8
+      vbindiff 3.0_beta4
+    ].each_slice(2).to_a.map do |formula, version|
+      [formula, version.sub(/\d+$/, "")]
+    end
+
+    gnome_devel_whitelist = %w[
+      gtk-doc 1.25
+      libart 2.3.21
+      pygtkglext 1.1.0
+    ].each_slice(2).to_a.map do |formula, version|
+      [formula, version.split(".")[0..1].join(".")]
+    end
+
     stable = formula.stable
     case stable && stable.url
     when /[\d\._-](alpha|beta|rc\d)/
-      problem "Stable version URLs should not contain #{$1}"
+      matched = $1
+      version_prefix = stable.version.to_s.sub(/\d+$/, "")
+      return if unstable_whitelist.include?([formula.name, version_prefix])
+      problem "Stable version URLs should not contain #{matched}"
     when %r{download\.gnome\.org/sources}, %r{ftp\.gnome\.org/pub/GNOME/sources}i
+      version_prefix = stable.version.to_s.split(".")[0..1].join(".")
+      return if gnome_devel_whitelist.include?([formula.name, version_prefix])
       version = Version.parse(stable.url)
       if version >= Version.create("1.0")
         minor_version = version.to_s.split(".", 3)[1].to_i