Accept coercion as a way to accept nil values

2 files changed, 12 insertions, 1 deletions

diff --git a/lib/chef/property.rb b/lib/chef/property.rb
index c1207d9132..e97d8f9607 100644
--- a/lib/chef/property.rb
+++ b/lib/chef/property.rb
@@ -479,6 +479,8 @@ class Chef
     # A type accepts nil explicitly if "is" allows nil, it validates as nil, *and* is not simply
     # an empty type.
     #
+    # A type is presumed to accept nil if it does coercion (which must handle nil).
+    #
     # These examples accept nil explicitly:
     # ```ruby
     # property :a, [ String, nil ]
@@ -510,7 +512,8 @@ class Chef
     #
     # @api private
     def explicitly_accepts_nil?(resource)
-      options.has_key?(:is) && resource.send(:_pv_is, { name => nil }, name, options[:is], raise_error: false)
+      options.has_key?(:coerce) ||
+      (options.has_key?(:is) && resource.send(:_pv_is, { name => nil }, name, options[:is], raise_error: false))
     end
 
     def get_value(resource)
diff --git a/spec/unit/property_spec.rb b/spec/unit/property_spec.rb
index 9ecf7a4cde..dc06cb3326 100644
--- a/spec/unit/property_spec.rb
+++ b/spec/unit/property_spec.rb
@@ -921,6 +921,9 @@ describe "Chef::Resource.property" do
         expect(resource.x 10).to eq "101"
         expect(Namer.current_index).to eq 1
       end
+      it "does not emit a deprecation warning if set to nil" do
+        expect(resource.x nil).to eq "1"
+      end
       it "coercion sets the value (and coercion does not run on get)" do
         expect(resource.x 10).to eq "101"
         expect(resource.x).to eq "101"
@@ -933,6 +936,11 @@ describe "Chef::Resource.property" do
         expect(Namer.current_index).to eq 2
       end
     end
+    with_property ':x, coerce: proc { |x| x }' do
+      it "does not emit a deprecation warning if set to nil" do
+        expect(resource.x nil).to be_nil
+      end
+    end
     with_property ':x, coerce: proc { |x| Namer.next_index; raise "hi" if x == 10; x }, is: proc { |x| Namer.next_index; x != 10 }' do
       it "failed coercion fails to set the value" do
         resource.x 20