emacs_requirement: allow no version

see Homebrew/homebrew-emacs#29

Closes Homebrew/homebrew#45426.

Signed-off-by: Alex Dunn <dunn.alex@gmail.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/Library/Homebrew/requirements/emacs_requirement.rb b/Library/Homebrew/requirements/emacs_requirement.rb
index 1da3ecd04..811810f07 100644
--- a/Library/Homebrew/requirements/emacs_requirement.rb
+++ b/Library/Homebrew/requirements/emacs_requirement.rb
@@ -4,12 +4,12 @@ class EmacsRequirement < Requirement
 
   def initialize(tags)
     @version = tags.shift if /\d+\.*\d*/ === tags.first
-    raise "Specify a version for EmacsRequirement" unless @version
     super
   end
 
   satisfy :build_env => false do
-    next unless which "emacs"
+    next false unless which "emacs"
+    next true unless @version
     emacs_version = Utils.popen_read("emacs", "--batch", "--eval", "(princ emacs-version)")
     Version.new(emacs_version) >= Version.new(@version)
   end
@@ -19,7 +19,11 @@ class EmacsRequirement < Requirement
   end
 
   def message
-    s = "Emacs #{@version} or later is required."
+    if @version
+      s = "Emacs #{@version} or later is required."
+    else
+      s = "Emacs is required."
+    end
     s += super
     s
   end