From 7adee6d62fabae0244d611069f09ab906a459805 Mon Sep 17 00:00:00 2001
From: Shaun Jackman <sjackman@gmail.com>
Date: Fri, 1 Dec 2017 15:00:27 -0800
Subject: [PATCH] Utils.popen_read: Nonexistent program should fail

Ensure that $CHILD_STATUS.success? is false when the command does not exist.
---
 Library/Homebrew/test/utils/popen_spec.rb |  6 ++++++
 Library/Homebrew/utils/popen.rb           | 10 +++++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/Library/Homebrew/test/utils/popen_spec.rb b/Library/Homebrew/test/utils/popen_spec.rb
index 63bbc7b18b..d1ae12d1c9 100644
--- a/Library/Homebrew/test/utils/popen_spec.rb
+++ b/Library/Homebrew/test/utils/popen_spec.rb
@@ -15,6 +15,12 @@ describe Utils do
       ).to eq("success")
       expect($CHILD_STATUS).to be_a_success
     end
+
+    it "fails when the command does not exist" do
+      expect(subject.popen_read("./nonexistent", err: :out))
+        .to eq("brew: command not found: ./nonexistent\n")
+      expect($CHILD_STATUS).to be_a_failure
+    end
   end
 
   describe "::popen_write" do
diff --git a/Library/Homebrew/utils/popen.rb b/Library/Homebrew/utils/popen.rb
index 2fa3ade462..21dceec069 100644
--- a/Library/Homebrew/utils/popen.rb
+++ b/Library/Homebrew/utils/popen.rb
@@ -14,7 +14,15 @@ module Utils
         yield pipe
       else
         options[:err] ||= :close unless ENV["HOMEBREW_STDERR"]
-        exec(*args, options)
+        begin
+          exec(*args, options)
+        rescue Errno::ENOENT
+          $stderr.puts "brew: command not found: #{args[0]}" unless options[:err] == :close
+          exit! 127
+        rescue SystemCallError
+          $stderr.puts "brew: exec failed: #{args[0]}" unless options[:err] == :close
+          exit! 1
+        end
       end
     end
   end