brew doctor now checks pkg-config search path

Homebrew's pkg-config didn't originally add X11 to its search path.
This causes problems for long-time Homebrew users brewing software
that depends on X11-related packages, such as Cairo.

1 files changed, 30 insertions, 2 deletions

diff --git a/Library/Homebrew/brew_doctor.rb b/Library/Homebrew/brew_doctor.rb
index 146755d49..37ab588f7 100644
--- a/Library/Homebrew/brew_doctor.rb
+++ b/Library/Homebrew/brew_doctor.rb
@@ -156,7 +156,7 @@ def check_user_path
   end
 end
 
-def check_pkg_config
+def check_which_pkg_config
   binary = `which pkg-config`.chomp
   return if binary.empty?
 
@@ -172,6 +172,33 @@ def check_pkg_config
   end
 end
 
+def check_pkg_config_paths
+  binary = `which pkg-config`.chomp
+  return if binary.empty?
+
+  # Use the debug output to determine which paths are searched
+  pkg_config_paths = []
+
+  debug_output = `pkg-config --debug 2>&1`
+  debug_output.split("\n").each do |line|
+    line =~ /Scanning directory '(.*)'/
+    pkg_config_paths << $1 if $1
+  end
+
+  # Check that all expected paths are being searched
+  unless pkg_config_paths.include? "/usr/X11/lib/pkgconfig"
+    puts <<-EOS.undent
+      Your pkg-config is not checking "/usr/X11/lib/pkgconfig" for packages.
+      Earlier versions of the pkg-config formula did not add this path
+      to the search path, which means that other formula may not be able
+      to find certain dependencies.
+
+      To resolve this issue, re-brew pkg-config with:
+        brew rm pkg-config && brew install pkg-config
+    EOS
+  end
+end
+
 def brew_doctor
   read, write = IO.pipe
 
@@ -187,7 +214,8 @@ def brew_doctor
     check_for_x11
     check_share_locale
     check_user_path
-    check_pkg_config
+    check_which_pkg_config
+    check_pkg_config_paths
 
     exit! 0
   else