Handle scenario where no value found in the update

Also add a pile of specs

Signed-off-by: Tim Smith <tsmith@chef.io>

2 files changed, 32 insertions, 2 deletions

diff --git a/lib/chef/resource/build_essential.rb b/lib/chef/resource/build_essential.rb
index 7b423b1412..cb54e45dd6 100644
--- a/lib/chef/resource/build_essential.rb
+++ b/lib/chef/resource/build_essential.rb
@@ -186,7 +186,7 @@ class Chef
           label_match = available_updates.stdout.match(/^\s*\* (?:Label: )?(Command Line Tools.*)/)
 
           # this will return the match or nil
-          label_match&.first
+          label_match[1] unless label_match.nil?
         end
       end
 
diff --git a/spec/unit/resource/build_essential_spec.rb b/spec/unit/resource/build_essential_spec.rb
index 8b412c94c2..62d7963ea2 100644
--- a/spec/unit/resource/build_essential_spec.rb
+++ b/spec/unit/resource/build_essential_spec.rb
@@ -1,5 +1,5 @@
 #
-# Copyright:: Copyright 2018, Chef Software, Inc.
+# Copyright:: Copyright 2018-2020, Chef Software, Inc.
 # License:: Apache License, Version 2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -25,6 +25,18 @@ describe Chef::Resource::BuildEssential do
   let(:resource) { Chef::Resource::BuildEssential.new("foo", run_context) }
   let(:provider) { resource.provider_for_action(:install) }
 
+  let(:softwareupdate_catalina_and_later) do
+    double("shell_out", exitstatus: 0, error!: nil, stdout: "Software Update Tool\n\nFinding available software\nSoftware Update found the following new or updated software:\n* Label: Command Line Tools for Xcode-11.0\n\tTitle: Command Line Tools for Xcode, Version: 11.0, Size: 224868K, Recommended: YES, \n")
+  end
+
+  let(:softwareupdate_catalina_and_later_no_cli) do
+    double("shell_out", exitstatus: 0, error!: nil, stdout: "Software Update Tool\n\nFinding available software\nSoftware Update found the following new or updated software:\n* Label: Chef Infra Client\n\tTitle: Chef Infra Client, Version: 17.0.208, Size: 224868K, Recommended: YES, \n")
+  end
+
+  let(:softwareupdate_pre_catalina) do
+    double("shell_out", exitstatus: 0, error!: nil, stdout: "Software Update Tool\n\nFinding available software\nSoftware Update found the following new or updated software:\n   * Command Line Tools (macOS High Sierra version 10.13) for Xcode-10.0\n")
+  end
+
   it "has a resource name of :build_essential" do
     expect(resource.resource_name).to eql(:build_essential)
   end
@@ -56,4 +68,22 @@ describe Chef::Resource::BuildEssential do
       expect(provider.xcode_cli_installed?).to eql(false)
     end
   end
+
+  describe "#xcode_cli_package_label" do
+    it "returns a package name on macOS < 10.15" do
+      allow(provider).to receive(:shell_out).with("softwareupdate", "--list").and_return(softwareupdate_pre_catalina)
+      expect(provider.xcode_cli_package_label).to eql("Command Line Tools (macOS High Sierra version 10.13) for Xcode-10.0")
+    end
+
+    it "returns a package name on macOS 10.15+" do
+      allow(provider).to receive(:shell_out).with("softwareupdate", "--list").and_return(softwareupdate_catalina_and_later)
+      expect(provider.xcode_cli_package_label).to eql("Command Line Tools for Xcode-11.0")
+    end
+
+    it "returns nil if no update is listed" do
+      allow(provider).to receive(:shell_out).with("softwareupdate", "--list").and_return(softwareupdate_catalina_and_later_no_cli)
+      expect(provider.xcode_cli_package_label).to be_nil
+    end
+
+  end
 end