From 4d3d8189a9c8e341475a80f2d22303a06573bcd3 Mon Sep 17 00:00:00 2001
From: Frederik Deweerdt <fdeweerdt@fastly.com>
Date: Mon, 10 Oct 2016 15:57:21 -0700
Subject: [PATCH 1/2] Add 'Project.provide()' for virtual packages

---
 lib/omnibus/packagers/rpm.rb |  1 +
 lib/omnibus/project.rb       | 26 ++++++++++++++++++++++++++
 resources/deb/control.erb    |  3 +++
 3 files changed, 30 insertions(+)

diff --git a/lib/omnibus/packagers/rpm.rb b/lib/omnibus/packagers/rpm.rb
index 97297e93a..ad890c92d 100644
--- a/lib/omnibus/packagers/rpm.rb
+++ b/lib/omnibus/packagers/rpm.rb
@@ -324,6 +324,7 @@ def write_rpm_spec
           category:        category,
           conflicts:       project.conflicts,
           replaces:        project.replaces,
+          provides:        project.provides,
           dependencies:    project.runtime_dependencies,
           user:            project.package_user,
           group:           project.package_group,
diff --git a/lib/omnibus/project.rb b/lib/omnibus/project.rb
index 3d249b370..1d781d22b 100644
--- a/lib/omnibus/project.rb
+++ b/lib/omnibus/project.rb
@@ -285,6 +285,23 @@ def description(val = NULL)
     end
     expose :description
 
+    #
+    # Add to the list of packages this one provides.
+    #
+    # @example
+    #   provide 'the-virtual-package'
+    #
+    # @param [String] val
+    #   the name of the package to provide
+    #
+    # @return [String]
+    #
+    def provide(val = NULL)
+      provides << val
+      provides.dup
+    end
+    expose :provide
+
     #
     # Add to the list of packages this one replaces.
     #
@@ -897,6 +914,15 @@ def replaces
       @replaces ||= []
     end
 
+    #
+    # The list of things this project provides.
+    #
+    # @return [Array<String>]
+    #
+    def provides
+      @provides ||= []
+    end
+
     #
     # The list of exclusions for this project.
     #
diff --git a/resources/deb/control.erb b/resources/deb/control.erb
index df91e3463..a8d834cb4 100644
--- a/resources/deb/control.erb
+++ b/resources/deb/control.erb
@@ -14,6 +14,9 @@ Conflicts: <%= conflicts.join(', ') %>
 <% unless replaces.empty? -%>
 Replaces: <%= replaces.join(', ') %>
 <% end -%>
+<% unless provides.empty? -%>
+Provides: <%= provides.join(', ') %>
+<% end -%>
 Section: <%= section %>
 Priority: <%= priority %>
 Homepage: <%= homepage %>

From 67f479392700fd7320b4705d85421e61bf37f5e1 Mon Sep 17 00:00:00 2001
From: Frederik Deweerdt <fdeweerdt@fastly.com>
Date: Mon, 10 Oct 2016 16:51:28 -0700
Subject: [PATCH 2/2] Fix unit tests

---
 lib/omnibus/packagers/deb.rb    | 1 +
 spec/unit/packagers/deb_spec.rb | 2 ++
 spec/unit/packagers/rpm_spec.rb | 1 +
 spec/unit/project_spec.rb       | 1 +
 4 files changed, 5 insertions(+)

diff --git a/lib/omnibus/packagers/deb.rb b/lib/omnibus/packagers/deb.rb
index 17525b17f..255b841c5 100644
--- a/lib/omnibus/packagers/deb.rb
+++ b/lib/omnibus/packagers/deb.rb
@@ -214,6 +214,7 @@ def write_control_file
           section:        section,
           conflicts:      project.conflicts,
           replaces:       project.replaces,
+          provides:       project.provides,
           dependencies:   project.runtime_dependencies,
         }
       )
diff --git a/spec/unit/packagers/deb_spec.rb b/spec/unit/packagers/deb_spec.rb
index fbb99bd51..7c80695a0 100644
--- a/spec/unit/packagers/deb_spec.rb
+++ b/spec/unit/packagers/deb_spec.rb
@@ -10,6 +10,7 @@ module Omnibus
         project.build_version("1.2.3")
         project.build_iteration("2")
         project.maintainer("Chef Software")
+        project.provide("chefy-package")
         project.license(project_license) if project_license
       end
     end
@@ -136,6 +137,7 @@ module Omnibus
         expect(contents).to include("Vendor: Omnibus <omnibus@getchef.com>")
         expect(contents).to include("Architecture: amd64")
         expect(contents).to include("Maintainer: Chef Software")
+        expect(contents).to include("Provides: chefy-package")
         expect(contents).to include("Installed-Size: 0")
         expect(contents).to include("Section: misc")
         expect(contents).to include("Priority: extra")
diff --git a/spec/unit/packagers/rpm_spec.rb b/spec/unit/packagers/rpm_spec.rb
index 28489452b..ef5d2c8ff 100644
--- a/spec/unit/packagers/rpm_spec.rb
+++ b/spec/unit/packagers/rpm_spec.rb
@@ -11,6 +11,7 @@ module Omnibus
         project.build_iteration("2")
         project.maintainer("Chef Software")
         project.replace("old-project")
+        project.provide("chefy-package")
         project.license(project_license) if project_license
       end
     end
diff --git a/spec/unit/project_spec.rb b/spec/unit/project_spec.rb
index f090a14db..edb11bec3 100644
--- a/spec/unit/project_spec.rb
+++ b/spec/unit/project_spec.rb
@@ -28,6 +28,7 @@ module Omnibus
     it_behaves_like "a cleanroom setter", :homepage, %{homepage 'https://getchef.com'}
     it_behaves_like "a cleanroom setter", :description, %{description 'Installs the thing'}
     it_behaves_like "a cleanroom setter", :replace, %{replace 'old-chef'}
+    it_behaves_like "a cleanroom setter", :provide, %{provide 'chefy-package'}
     it_behaves_like "a cleanroom setter", :conflict, %{conflict 'puppet'}
     it_behaves_like "a cleanroom setter", :build_version, %{build_version '1.2.3'}
     it_behaves_like "a cleanroom setter", :build_iteration, %{build_iteration 1}