Fix custom_properties diffing when config uses property_name (#978)

* Initial plan

* Handle alternate custom property name shapes in normalize

* Add explicit object guard in custom property normalization

* Support property_name in custom_properties config entries

* Polish custom properties test descriptions

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

Author: Copilot

lib/plugins/custom_properties.js

@@ -12,12 +12,24 @@ module.exports = class CustomProperties extends Diffable {
 
   // Force all names to lowercase to avoid comparison issues.
   normalizeEntries () {
-    this.entries = this.entries
-      .filter(({ name }) => name != null)
-      .map(({ name, value }) => ({
-        name: name.toLowerCase(),
-        value
-      }))
+    this.entries = this.entries.reduce((normalizedEntries, entry) => {
+      if (!entry || typeof entry !== 'object') {
+        return normalizedEntries
+      }
+
+      const entryName = entry.name || entry.property_name
+
+      if (typeof entryName !== 'string') {
+        return normalizedEntries
+      }
+
+      normalizedEntries.push({
+        name: entryName.toLowerCase(),
+        value: entry.value
+      })
+
+      return normalizedEntries
+    }, [])
   }
 
   async find () {
@@ -40,12 +52,24 @@ module.exports = class CustomProperties extends Diffable {
 
   // Force all names to lowercase to avoid comparison issues.
   normalize (properties) {
-    return properties
-      .filter(({ property_name: propertyName }) => propertyName != null)
-      .map(({ property_name: propertyName, value }) => ({
+    return properties.reduce((normalizedProperties, property) => {
+      if (!property || typeof property !== 'object') {
+        return normalizedProperties
+      }
+
+      const propertyName = property.property_name || property.name
+
+      if (typeof propertyName !== 'string') {
+        return normalizedProperties
+      }
+
+      normalizedProperties.push({
         name: propertyName.toLowerCase(),
-        value
-      }))
+        value: property.value
+      })
+
+      return normalizedProperties
+    }, [])
   }
 
   comparator (existing, attrs) {

test/unit/lib/plugins/custom_properties.test.js

@@ -27,11 +27,16 @@ describe('CustomProperties', () => {
   })
 
   describe('Custom Properties plugin', () => {
-    it('should normalize entries when be instantiated', () => {
+    it('should normalize entries when instantiated', () => {
       const plugin = configure([{ name: 'Test', value: 'test' }])
       expect(plugin.entries).toEqual([{ name: 'test', value: 'test' }])
     })
 
+    it('should normalize entries with property_name when instantiated', () => {
+      const plugin = configure([{ property_name: 'ent-ownership', value: 'expert-services' }])
+      expect(plugin.entries).toEqual([{ name: 'ent-ownership', value: 'expert-services' }])
+    })
+
     it('should fetch and normalize custom properties successfully', async () => {
       const mockResponse = [
         { property_name: 'Test1', value: 'value1' },
@@ -58,6 +63,24 @@ describe('CustomProperties', () => {
       ])
     })
 
+    it('should normalize paginated custom properties when property name shape differs', async () => {
+      const mockResponse = [
+        { name: 'Owner', value: 'My Team' },
+        { property_name: 'Criticality', value: 'High' },
+        { value: 'ignored' }
+      ]
+
+      github.paginate.mockResolvedValue(mockResponse)
+
+      const plugin = configure()
+      const result = await plugin.find()
+
+      expect(result).toEqual([
+        { name: 'owner', value: 'My Team' },
+        { name: 'criticality', value: 'High' }
+      ])
+    })
+
     it('should sync', async () => {
       const mockResponse = [
         { property_name: 'no-change', value: 'no-change' },