Sort identical "provides" alphabetically (for backcompat)

- Warn when multiple providers try to provide the same thing

16 files changed, 131 insertions, 107 deletions

diff --git a/lib/chef/chef_class.rb b/lib/chef/chef_class.rb
index f1dd797c04..a0c74f7aec 100644
--- a/lib/chef/chef_class.rb
+++ b/lib/chef/chef_class.rb
@@ -58,7 +58,7 @@ class Chef
     # @return [Array<Class>] Priority Array of Provider Classes to use for the resource_name on the node
     #
     def get_provider_priority_array(resource_name)
-      result = provider_priority_map.get_priority_array(node, resource_name)
+      result = provider_priority_map.get_priority_array(node, resource_name.to_sym)
       result = result.dup if result
       result
     end
@@ -71,7 +71,7 @@ class Chef
     # @return [Array<Class>] Priority Array of Resource Classes to use for the resource_name on the node
     #
     def get_resource_priority_array(resource_name)
-      result = resource_priority_map.get_priority_array(node, resource_name)
+      result = resource_priority_map.get_priority_array(node, resource_name.to_sym)
       result = result.dup if result
       result
     end
@@ -86,7 +86,7 @@ class Chef
     # @return [Array<Class>] Modified Priority Array of Provider Classes to use for the resource_name on the node
     #
     def set_provider_priority_array(resource_name, priority_array, *filter, &block)
-      result = provider_priority_map.set_priority_array(resource_name, priority_array, *filter, &block)
+      result = provider_priority_map.set_priority_array(resource_name.to_sym, priority_array, *filter, &block)
       result = result.dup if result
       result
     end
@@ -101,7 +101,7 @@ class Chef
     # @return [Array<Class>] Modified Priority Array of Resource Classes to use for the resource_name on the node
     #
     def set_resource_priority_array(resource_name, priority_array, *filter, &block)
-      result = resource_priority_map.set_priority_array(resource_name, priority_array, *filter, &block)
+      result = resource_priority_map.set_priority_array(resource_name.to_sym, priority_array, *filter, &block)
       result = result.dup if result
       result
     end
diff --git a/lib/chef/node_map.rb b/lib/chef/node_map.rb
index f547018a38..d5eed7c215 100644
--- a/lib/chef/node_map.rb
+++ b/lib/chef/node_map.rb
@@ -38,30 +38,35 @@ class Chef
     #
     # @return [NodeMap] Returns self for possible chaining
     #
-    def set(key, value, platform: nil, platform_version: nil, platform_family: nil, os: nil, on_platform: nil, on_platforms: nil, canonical: nil, &block)
+    def set(key, value, platform: nil, platform_version: nil, platform_family: nil, os: nil, on_platform: nil, on_platforms: nil, canonical: nil, override: nil, &block)
       Chef::Log.deprecation "The on_platform option to node_map has been deprecated" if on_platform
       Chef::Log.deprecation "The on_platforms option to node_map has been deprecated" if on_platforms
       platform ||= on_platform || on_platforms
-      filters = { platform: platform, platform_version: platform_version, platform_family: platform_family, os: os }
-      new_matcher = { filters: filters, block: block, value: value, canonical: canonical }
-      @map[key] ||= []
-      # Decide where to insert the matcher; the new value is preferred over
-      # anything more specific (see `priority_of`) and is preferred over older
-      # values of the same specificity.  (So all other things being equal,
-      # newest wins.)
+      filters = {}
+      filters[:platform] = platform if platform
+      filters[:platform_version] = platform_version if platform_version
+      filters[:platform_family] = platform_family if platform_family
+      filters[:os] = os if os
+      new_matcher = { value: value, filters: filters }
+      new_matcher[:block] = block if block
+      new_matcher[:canonical] = canonical if canonical
+      new_matcher[:override] = override if override
+
+      # The map is sorted in order of preference already; we just need to find
+      # our place in it (just before the first value with the same preference level).
       insert_at = nil
-      @map[key].each_with_index do |matcher, index|
-        if specificity(new_matcher) >= specificity(matcher)
-          insert_at = index
-          break
-        end
+      @map[key] ||= []
+      @map[key].each_with_index do |matcher,index|
+        cmp = compare_matchers(key, new_matcher, matcher)
+        insert_at ||= index if cmp && cmp <= 0
       end
       if insert_at
         @map[key].insert(insert_at, new_matcher)
       else
         @map[key] << new_matcher
       end
-      self
+      insert_at ||= @map[key].size - 1
+      @map
     end
 
     #
@@ -116,30 +121,7 @@ class Chef
       remaining
     end
 
-    private
-
-    #
-    # Gives a value for "how specific" the matcher is.
-    # Things which specify more specific filters get a higher number
-    # (platform_version > platform > platform_family > os); things
-    # with a block have higher specificity than similar things without
-    # a block.
-    #
-    def specificity(matcher)
-      if matcher[:filters][:platform_version]
-        specificity = 8
-      elsif matcher[:filters][:platform]
-        specificity = 6
-      elsif matcher[:filters][:platform_family]
-        specificity = 4
-      elsif matcher[:filters][:os]
-        specificity = 2
-      else
-        specificity = 0
-      end
-      specificity += 1 if matcher[:block]
-      specificity
-    end
+    protected
 
     #
     # Succeeds if:
@@ -197,5 +179,48 @@ class Chef
       return true if canonical.nil?
       !!canonical == !!matcher[:canonical]
     end
+
+    def compare_matchers(key, new_matcher, matcher)
+      cmp = compare_matcher_properties(new_matcher, matcher) { |m| m[:filters][:block] }
+      return cmp if cmp != 0
+      cmp = compare_matcher_properties(new_matcher, matcher) { |m| m[:filters][:platform_version] }
+      return cmp if cmp != 0
+      cmp = compare_matcher_properties(new_matcher, matcher) { |m| m[:filters][:platform] }
+      return cmp if cmp != 0
+      cmp = compare_matcher_properties(new_matcher, matcher) { |m| m[:filters][:platform_family] }
+      return cmp if cmp != 0
+      cmp = compare_matcher_properties(new_matcher, matcher) { |m| m[:filters][:os] }
+      return cmp if cmp != 0
+      cmp = compare_matcher_properties(new_matcher, matcher) { |m| m[:override] }
+      return cmp if cmp != 0
+      # If all things are identical, return 0
+      0
+    end
+
+    def compare_matcher_properties(new_matcher, matcher)
+      a = yield(new_matcher)
+      b = yield(matcher)
+
+      # Check for blcacklists ('!windows'). Those always come *after* positive
+      # whitelists.
+      a_negated = Array(a).any? { |f| f.is_a?(String) && f.start_with?('!') }
+      b_negated = Array(b).any? { |f| f.is_a?(String) && f.start_with?('!') }
+      if a_negated != b_negated
+        return 1 if a_negated
+        return -1 if b_negated
+      end
+
+      # We treat false / true and nil / not-nil with the same comparison
+      a = nil if a == false
+      b = nil if b == false
+      cmp = a <=> b
+      # This is the case where one is non-nil, and one is nil. The one that is
+      # nil is "greater" (i.e. it should come last).
+      if cmp.nil?
+        return 1 if a.nil?
+        return -1 if b.nil?
+      end
+      cmp
+    end
   end
 end
diff --git a/lib/chef/platform/priority_map.rb b/lib/chef/platform/priority_map.rb
new file mode 100644
index 0000000000..3608975b51
--- /dev/null
+++ b/lib/chef/platform/priority_map.rb
@@ -0,0 +1,50 @@
+require 'chef/node_map'
+
+class Chef
+  class Platform
+    class PriorityMap < Chef::NodeMap
+      # @api private
+      def get_priority_array(node, key)
+        get(node, key)
+      end
+
+      # @api private
+      def set_priority_array(key, priority_array, *filter, &block)
+        priority_array = Array(priority_array)
+        set(key, priority_array, *filter, &block)
+        priority_array
+      end
+
+      # @api private
+      def list_handlers(node, key, **filters)
+        list(node, key, **filters).flatten(1).uniq
+      end
+
+      #
+      # Priority maps have one extra precedence: priority arrays override "provides,"
+      # and "provides" lines with identical filters sort by class name (ascending).
+      #
+      def compare_matchers(key, new_matcher, matcher)
+        # Priority arrays come before "provides"
+        if new_matcher[:value].is_a?(Array) != matcher[:value].is_a?(Array)
+          return new_matcher[:value].is_a?(Array) ? -1 : 1
+        end
+
+        cmp = super
+        if cmp == 0
+          # Sort by class name (ascending) as well, if all other properties
+          # are exactly equal
+          if new_matcher[:value].is_a?(Class) && !new_matcher[:override]
+            cmp = compare_matcher_properties(new_matcher, matcher) { |m| m[:value].name }
+            if cmp < 0
+              Chef::Log.warn "You are overriding #{key} on #{new_matcher[:filters].inspect} with #{new_matcher[:value].inspect}: used to be #{matcher[:value].inspect}. Use override: true if this is what you intended."
+            elsif cmp > 0
+              Chef::Log.warn "You declared a new resource #{new_matcher[:value].inspect} for resource #{key}, but it comes alphabetically after #{matcher[:value].inspect} and has the same filters (#{new_matcher[:filters].inspect}), so it will not be used. Use override: true if you want to use it for #{key}."
+            end
+          end
+        end
+        cmp
+      end
+    end
+  end
+end
diff --git a/lib/chef/platform/provider_mapping.rb b/lib/chef/platform/provider_mapping.rb
index e3a894c8ac..af17d8e1b4 100644
--- a/lib/chef/platform/provider_mapping.rb
+++ b/lib/chef/platform/provider_mapping.rb
@@ -201,8 +201,8 @@ class Chef
 
             begin
               result = Chef::Provider.const_get(class_name)
-              Chef::Log.warn("Class Chef::Provider::#{class_name} does not declare 'provides #{convert_to_snake_case(class_name).to_sym.inspect}'.")
-              Chef::Log.warn("This will no longer work in Chef 13: you must use 'provides' to provide DSL.")
+              Chef::Log.warn("Class Chef::Provider::#{class_name} does not declare 'resource_name #{convert_to_snake_case(class_name).to_sym.inspect}'.")
+              Chef::Log.warn("This will no longer work in Chef 13: you must use 'resource_name' to provide DSL.")
             rescue NameError
             end
           end
diff --git a/lib/chef/platform/provider_priority_map.rb b/lib/chef/platform/provider_priority_map.rb
index 9d703c9178..5599c74c2d 100644
--- a/lib/chef/platform/provider_priority_map.rb
+++ b/lib/chef/platform/provider_priority_map.rb
@@ -1,29 +1,11 @@
 require 'singleton'
+require 'chef/platform/priority_map'
 
 class Chef
   class Platform
-    class ProviderPriorityMap
+    # @api private
+    class ProviderPriorityMap < Chef::Platform::PriorityMap
       include Singleton
-
-      def get_priority_array(node, resource_name)
-        priority_map.get(node, resource_name.to_sym)
-      end
-
-      def set_priority_array(resource_name, priority_array, *filter, &block)
-        priority_map.set(resource_name.to_sym, Array(priority_array), *filter, &block)
-      end
-
-      # @api private
-      def list_handlers(node, resource_name)
-        priority_map.list(node, resource_name.to_sym).flatten(1).uniq
-      end
-
-      private
-
-      def priority_map
-        require 'chef/node_map'
-        @priority_map ||= Chef::NodeMap.new
-      end
     end
   end
 end
diff --git a/lib/chef/platform/resource_priority_map.rb b/lib/chef/platform/resource_priority_map.rb
index fb08debc53..aa57e3ddf0 100644
--- a/lib/chef/platform/resource_priority_map.rb
+++ b/lib/chef/platform/resource_priority_map.rb
@@ -1,34 +1,17 @@
 require 'singleton'
+require 'chef/platform/priority_map'
 
 class Chef
   class Platform
-    class ResourcePriorityMap
+    # @api private
+    class ResourcePriorityMap < Chef::Platform::PriorityMap
       include Singleton
 
-      def get_priority_array(node, resource_name, canonical: nil)
-        priority_map.get(node, resource_name.to_sym, canonical: canonical)
-      end
-
-      def set_priority_array(resource_name, priority_array, *filter, &block)
-        priority_map.set(resource_name.to_sym, Array(priority_array), *filter, &block)
-      end
-
       # @api private
-      def delete_canonical(resource_name, resource_class)
-        priority_map.delete_canonical(resource_name, resource_class)
-      end
-
-      # @api private
-      def list_handlers(*args)
-        priority_map.list(*args).flatten(1).uniq
+      def get_priority_array(node, resource_name, canonical: nil)
+        super(node, resource_name.to_sym, canonical: canonical)
       end
 
-      private
-
-      def priority_map
-        require 'chef/node_map'
-        @priority_map ||= Chef::NodeMap.new
-      end
     end
   end
 end
diff --git a/lib/chef/provider.rb b/lib/chef/provider.rb
index e50e374804..131b72cd23 100644
--- a/lib/chef/provider.rb
+++ b/lib/chef/provider.rb
@@ -176,7 +176,7 @@ class Chef
     end
 
     def self.provides(short_name, opts={}, &block)
-      Chef.set_provider_priority_array(short_name, self, opts, &block)
+      Chef.provider_priority_map.set(short_name, self, opts, &block)
     end
 
     def self.provides?(node, resource)
diff --git a/lib/chef/provider/service/debian.rb b/lib/chef/provider/service/debian.rb
index 01505924cb..c67f3f05da 100644
--- a/lib/chef/provider/service/debian.rb
+++ b/lib/chef/provider/service/debian.rb
@@ -25,8 +25,6 @@ class Chef
         UPDATE_RC_D_ENABLED_MATCHES = /\/rc[\dS].d\/S|not installed/i
         UPDATE_RC_D_PRIORITIES = /\/rc([\dS]).d\/([SK])(\d\d)/i
 
-        provides :service, platform_family: "debian"
-
         def self.provides?(node, resource)
           super && Chef::Platform::ServiceHelpers.service_resource_providers.include?(:debian)
         end
diff --git a/lib/chef/provider/service/insserv.rb b/lib/chef/provider/service/insserv.rb
index 31965a4bc6..4534e33f32 100644
--- a/lib/chef/provider/service/insserv.rb
+++ b/lib/chef/provider/service/insserv.rb
@@ -24,8 +24,6 @@ class Chef
     class Service
       class Insserv < Chef::Provider::Service::Init
 
-        provides :service, os: "linux"
-
         def self.provides?(node, resource)
           super && Chef::Platform::ServiceHelpers.service_resource_providers.include?(:insserv)
         end
diff --git a/lib/chef/provider/service/invokercd.rb b/lib/chef/provider/service/invokercd.rb
index 5ff24e0dbb..fdf4cbc256 100644
--- a/lib/chef/provider/service/invokercd.rb
+++ b/lib/chef/provider/service/invokercd.rb
@@ -23,8 +23,6 @@ class Chef
     class Service
       class Invokercd < Chef::Provider::Service::Init
 
-        provides :service, platform_family: "debian"
-
         def self.provides?(node, resource)
           super && Chef::Platform::ServiceHelpers.service_resource_providers.include?(:invokercd)
         end
diff --git a/lib/chef/provider/service/redhat.rb b/lib/chef/provider/service/redhat.rb
index 850953125e..a8deb13aec 100644
--- a/lib/chef/provider/service/redhat.rb
+++ b/lib/chef/provider/service/redhat.rb
@@ -26,8 +26,6 @@ class Chef
         CHKCONFIG_ON = /\d:on/
         CHKCONFIG_MISSING = /No such/
 
-        provides :service, platform_family: [ "rhel", "fedora", "suse" ]
-
         def self.provides?(node, resource)
           super && Chef::Platform::ServiceHelpers.service_resource_providers.include?(:redhat)
         end
diff --git a/lib/chef/provider/service/upstart.rb b/lib/chef/provider/service/upstart.rb
index 8d4aa41035..d8ce6af649 100644
--- a/lib/chef/provider/service/upstart.rb
+++ b/lib/chef/provider/service/upstart.rb
@@ -27,8 +27,6 @@ class Chef
       class Upstart < Chef::Provider::Service::Simple
         UPSTART_STATE_FORMAT = /\w+ \(?(\w+)\)?[\/ ](\w+)/
 
-        provides :service, os: "linux"
-
         def self.provides?(node, resource)
           super && Chef::Platform::ServiceHelpers.service_resource_providers.include?(:upstart)
         end
diff --git a/lib/chef/provider/user.rb b/lib/chef/provider/user.rb
index ad92a72a0a..244b11db98 100644
--- a/lib/chef/provider/user.rb
+++ b/lib/chef/provider/user.rb
@@ -23,8 +23,6 @@ require 'etc'
 class Chef
   class Provider
     class User < Chef::Provider
-      provides :user
-
       include Chef::Mixin::Command
 
       attr_accessor :user_exists, :locked
diff --git a/lib/chef/resource.rb b/lib/chef/resource.rb
index 10ad184506..418b0dc1ce 100644
--- a/lib/chef/resource.rb
+++ b/lib/chef/resource.rb
@@ -1143,7 +1143,7 @@ class Chef
         remove_canonical_dsl
       end
 
-      result = Chef.set_resource_priority_array(name, self, options, &block)
+      result = Chef.resource_priority_map.set(name, self, options, &block)
       Chef::DSL::Resources.add_resource_dsl(name)
       result
     end
diff --git a/lib/chef/resource/macports_package.rb b/lib/chef/resource/macports_package.rb
index 937839b6e1..5843016897 100644
--- a/lib/chef/resource/macports_package.rb
+++ b/lib/chef/resource/macports_package.rb
@@ -16,10 +16,11 @@
 # limitations under the License.
 #
 
+require 'chef/resource/package'
+
 class Chef
   class Resource
     class MacportsPackage < Chef::Resource::Package
-      provides :package, os: "darwin"
     end
   end
 end
diff --git a/lib/chef/resource/package.rb b/lib/chef/resource/package.rb
index 1c6da75678..5be1c34b89 100644
--- a/lib/chef/resource/package.rb
+++ b/lib/chef/resource/package.rb
@@ -100,8 +100,3 @@ class Chef
     end
   end
 end
-
-require 'chef/chef_class'
-require 'chef/resource/homebrew_package'
-
-Chef.set_resource_priority_array :package, Chef::Resource::HomebrewPackage, os: "darwin"