Extend AccountPublic to allow retrieval of Factory and Filter capabil…

…ities (#153)

Without this, it's very difficult to detect whether a certain capability
is allowed to be retrieved unless you run scripts manually. With helper
methods like this (I'm sure others will be needed), you can borrow and
return details of the filter/factory yourself and then process them
offline

contracts/HybridCustody.cdc

@@ -198,6 +198,8 @@ pub contract HybridCustody {
         pub fun getPublicCapability(path: PublicPath, type: Type): Capability?
         pub fun getPublicCapFromDelegator(type: Type): Capability?
         pub fun getAddress(): Address
+        pub fun getCapabilityFactoryManager(): &{CapabilityFactory.Getter}?
+        pub fun getCapabilityFilter(): &{CapabilityFilter.Filter}?
     }
 
     /// Methods accessible to the designated parent of a ChildAccount
@@ -716,6 +718,18 @@ pub contract HybridCustody {
             self.resources <- {}
         }
 
+        /// Returns a capability to this child account's CapabilityFilter
+        ///
+        pub fun getCapabilityFilter(): &{CapabilityFilter.Filter}? {
+            return self.filter.check() ? self.filter.borrow() : nil
+        }
+
+        /// Returns a capability to this child account's CapabilityFactory
+        ///
+        pub fun getCapabilityFactoryManager(): &{CapabilityFactory.Getter}? {
+            return self.factory.check() ? self.factory.borrow() : nil
+        }
+
         destroy () {
             destroy <- self.resources
         }

scripts/test/can_get_child_factory_and_filter_caps.cdc

@@ -0,0 +1,19 @@
+import "HybridCustody"
+
+// @addr - The address of the child account
+// @parent - The parent account that this child is assigned to
+pub fun main(addr: Address, parent: Address): Bool {
+    let identifier = HybridCustody.getChildAccountIdentifier(parent)
+    let path = PrivatePath(identifier: identifier) ?? panic("invalid public path identifier for parent address")
+
+    let acctPublic = getAuthAccount(addr).getCapability<&HybridCustody.ChildAccount{HybridCustody.AccountPublic}>(path)
+        .borrow() ?? panic("account public not found")
+
+    let factory = acctPublic.getCapabilityFactoryManager()
+    assert(factory != nil, message: "capability factory is not valid")
+
+    let filter = acctPublic.getCapabilityFilter()
+    assert(filter != nil, message: "capability filter is not valid")
+
+    return true
+}

test/HybridCustody_tests.cdc

@@ -797,6 +797,14 @@ pub fun testRemoveParent() {
     txExecutor("hybrid-custody/remove_parent_from_child.cdc", [child], [parent.address], nil, nil)
 }
 
+pub fun testGetChildAccountCapabilityFilterAndFactory() {
+    let child = blockchain.createAccount()
+    let parent = blockchain.createAccount()
+
+    setupChildAndParent_FilterKindAll(child: child, parent: parent)
+    scriptExecutor("test/can_get_child_factory_and_filter_caps.cdc", [child.address, parent.address])
+}
+
 // --------------- End Test Cases ---------------