Merge pull request #28 from gravitystorm/one_zoom

Fix a bug with single-zoom layers

Author: systemed

.rubocop.yml

@@ -9,3 +9,5 @@ AllCops:
 
 Naming/MethodParameterName:
   AllowedNames: ['op', 'kv', 'k', 'id']
+RSpec/MultipleExpectations:
+  Max: 3

lib/glug/layer.rb

@@ -253,8 +253,8 @@ def to_hash
 
       # Convert zoom level
       if (v = hash['zoom'])
-        hash['minzoom'] = v.is_a?(Range) ? v.first : value
-        hash['maxzoom'] = v.is_a?(Range) ? v.last : value
+        hash['minzoom'] = v.is_a?(Range) ? v.first : v
+        hash['maxzoom'] = v.is_a?(Range) ? v.last : v
         hash.delete('zoom')
       end
 

spec/lib/glug/layer_spec.rb

@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+describe Glug::Layer do
+  describe 'zoom levels' do
+    it 'treats an integer as both min and max' do
+      stylesheet = Glug::Stylesheet.new do
+        source :osm_data, type: 'vector', url: 'http://example.com/osm.tilejson', default: true
+      end
+      l = described_class.new(stylesheet, { zoom: 7 })
+      l.line_width 1
+
+      h = l.to_hash
+      expect(h['minzoom']).to be(7)
+      expect(h['maxzoom']).to be(7)
+    end
+
+    it 'splits a range into min and max' do
+      stylesheet = Glug::Stylesheet.new do
+        source :osm_data, type: 'vector', url: 'http://example.com/osm.tilejson', default: true
+      end
+      l = described_class.new(stylesheet, { zoom: 1..5 })
+      l.line_width 1
+
+      h = l.to_hash
+      expect(h['minzoom']).to be(1)
+      expect(h['maxzoom']).to be(5)
+    end
+  end
+end