feat: Unknown lookup status of a path in certificate yields error

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 # UNRELEASED
 
+### feat: Updated handling of missing values in state tree certificates
+
+The `Unknown` lookup of a path in a certificate results in an `AgentError` (the IC returns `Absent` for non-existing paths).
+
 ### fix: dfx deploy urls printed for asset canisters
 
 ### chore: --emulator parameter is deprecated and will be discontinued soon

src/dfx/src/lib/state_tree/canister_info.rs

@@ -12,7 +12,7 @@ pub async fn read_state_tree_canister_controllers(
         .read_state_canister_info(canister_id, "controllers")
         .await
     {
-        Err(AgentError::LookupPathUnknown(_) | AgentError::LookupPathAbsent(_)) => {
+        Err(AgentError::LookupPathAbsent(_)) => {
             return Ok(None);
         }
         r => r.with_context(|| format!("Failed to read controllers of canister {canister_id}."))?,
@@ -57,10 +57,7 @@ pub async fn read_state_tree_canister_module_hash(
         .await
     {
         Ok(blob) => Some(blob),
-        // If the canister is empty, this path does not exist.
-        // The replica doesn't support negative lookups, therefore if the canister
-        // is empty, the replica will return lookup_path([], Pruned _) = Unknown
-        Err(AgentError::LookupPathUnknown(_)) | Err(AgentError::LookupPathAbsent(_)) => None,
+        Err(AgentError::LookupPathAbsent(_)) => None,
         Err(x) => bail!(x),
     };