From 7080ad5ebc58a472c6159c3218c273ee047a3d39 Mon Sep 17 00:00:00 2001
From: Maxim Belkin <maxim.belkin@gmail.com>
Date: Tue, 21 Jul 2020 12:50:22 +0000
Subject: [PATCH] formula.rb: update missing libs feature

1. Raise an exception on macOS.
2. Verify that the missing libraries are specified either as Strings or
   Regular Expressions.

Signed-off-by: Maxim Belkin <maxim.belkin@gmail.com>
---
 Library/Homebrew/extend/os/linux/formula.rb | 12 +++++++++---
 Library/Homebrew/formula.rb                 |  4 ++++
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/Library/Homebrew/extend/os/linux/formula.rb b/Library/Homebrew/extend/os/linux/formula.rb
index 12b28db2a0..f633b52416 100644
--- a/Library/Homebrew/extend/os/linux/formula.rb
+++ b/Library/Homebrew/extend/os/linux/formula.rb
@@ -19,7 +19,7 @@ class Formula
       when Regexp
         x.match? lib
       when String
-        lib.include? x
+        lib.to_s.include? x
       end
     end
   end
@@ -31,9 +31,15 @@ class Formula
       yield
     end
 
+    undef ignore_missing_libraries
+
     def ignore_missing_libraries(*libs)
-      libs.flatten!
-      allowed_missing_libraries.merge(libs)
+      libraries = libs.flatten
+      unless libraries.all? { |x| x.is_a?(String) || x.is_a?(Regexp) }
+        raise FormulaSpecificationError, "#{__method__} can handle Strings and Regular Expressions only"
+      end
+
+      allowed_missing_libraries.merge(libraries)
     end
 
     # @private
diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 06084522f6..834b6ab4ea 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -2763,6 +2763,10 @@ class Formula
     def link_overwrite_paths
       @link_overwrite_paths ||= Set.new
     end
+
+    def ignore_missing_libraries(*)
+      raise FormulaSpecificationError, "#{__method__} is available on Linux only"
+    end
   end
 end