formula_versions: add version_attributes_map.

This allows querying multiple attributes in the same way as
`revision_map` did but without duplicating code or repeatedly traversing
history.

1 files changed, 13 insertions, 5 deletions

diff --git a/Library/Homebrew/formula_versions.rb b/Library/Homebrew/formula_versions.rb
index 13cb8ac8c..2c5aae8f5 100644
--- a/Library/Homebrew/formula_versions.rb
+++ b/Library/Homebrew/formula_versions.rb
@@ -60,14 +60,22 @@ class FormulaVersions
     map
   end
 
-  def revision_map(branch)
-    map = Hash.new { |h, k| h[k] = [] }
+  def version_attributes_map(attributes, branch)
+    attributes_map = {}
+    return attributes_map if attributes.empty?
+    attributes.each do |attribute|
+      attributes_map[attribute] = Hash.new { |h, k| h[k] = [] }
+    end
+
     rev_list(branch) do |rev|
       formula_at_revision(rev) do |f|
-        map[f.stable.version] << f.revision if f.stable
-        map[f.devel.version] << f.revision if f.devel
+        attributes.each do |attribute|
+          map = attributes_map[attribute]
+          map[f.stable.version] << f.send(attribute) if f.stable
+          map[f.devel.version] << f.send(attribute) if f.devel
+        end
       end
     end
-    map
+    attributes_map
   end
 end