Fix Rent exempt check (#145)

Author: deanmlittle

harness/src/lib.rs

@@ -492,8 +492,8 @@ pub struct Mollusk {
     pub sysvars: Sysvars,
 
     /// The callback which can be used to inspect invoke_context
-    /// and extract low-level information such as bpf traces, transaction context,
-    /// detailed timings, etc.
+    /// and extract low-level information such as bpf traces, transaction
+    /// context, detailed timings, etc.
     #[cfg(feature = "invocation-inspect-callback")]
     pub invocation_inspect_callback: Box<dyn InvocationInspectCallback>,
 
@@ -524,13 +524,7 @@ pub struct EmptyInvocationInspectCallback;
 
 #[cfg(feature = "invocation-inspect-callback")]
 impl InvocationInspectCallback for EmptyInvocationInspectCallback {
-    fn before_invocation(
-        &self,
-        _: &Pubkey,
-        _: &[u8],
-        _: &[InstructionAccount],
-        _: &InvokeContext,
-    ) {
+    fn before_invocation(&self, _: &Pubkey, _: &[u8], _: &[InstructionAccount], _: &InvokeContext) {
     }
 
     fn after_invocation(&self, _: &InvokeContext) {}
@@ -577,8 +571,9 @@ impl Default for Mollusk {
 }
 
 impl CheckContext for Mollusk {
-    fn is_rent_exempt(&self, lamports: u64, space: usize) -> bool {
-        self.sysvars.rent.is_exempt(lamports, space)
+    fn is_rent_exempt(&self, lamports: u64, space: usize, owner: Pubkey) -> bool {
+        owner.eq(&Pubkey::default()) && lamports == 0
+            || self.sysvars.rent.is_exempt(lamports, space)
     }
 }
 

harness/tests/bpf_program.rs

@@ -471,8 +471,8 @@ fn test_account_checks_rent_exemption() {
     }
 
     impl CheckContext for TestCheckContext<'_> {
-        fn is_rent_exempt(&self, lamports: u64, space: usize) -> bool {
-            self.rent.is_exempt(lamports, space)
+        fn is_rent_exempt(&self, lamports: u64, space: usize, owner: Pubkey) -> bool {
+            owner.eq(&Pubkey::default()) && lamports == 0 || self.rent.is_exempt(lamports, space)
         }
     }
 

result/src/check.rs

@@ -253,7 +253,8 @@ impl InstructionResult {
                                     true,
                                     context.is_rent_exempt(
                                         resulting_account.lamports,
-                                        resulting_account.data.len()
+                                        resulting_account.data.len(),
+                                        resulting_account.owner,
                                     ),
                                 );
                             }
@@ -280,8 +281,11 @@ impl InstructionResult {
                 }
                 CheckType::AllRentExempt => {
                     for (pubkey, account) in &self.resulting_accounts {
-                        let is_rent_exempt =
-                            context.is_rent_exempt(account.lamports(), account.data().len());
+                        let is_rent_exempt = context.is_rent_exempt(
+                            account.lamports(),
+                            account.data().len(),
+                            account.owner,
+                        );
                         if !is_rent_exempt {
                             pass &= throw!(
                                 c,

result/src/config.rs

@@ -1,6 +1,6 @@
 //! Configuration and context for result validation.
 
-use solana_rent::Rent;
+use {solana_pubkey::Pubkey, solana_rent::Rent};
 
 pub struct Config {
     pub panic: bool,
@@ -24,8 +24,8 @@ impl Default for Config {
 /// one may wish to evaluate resulting account lamports with a custom `Rent`
 /// configuration. This trait allows such customization.
 pub trait CheckContext {
-    fn is_rent_exempt(&self, lamports: u64, space: usize) -> bool {
-        Rent::default().is_exempt(lamports, space)
+    fn is_rent_exempt(&self, lamports: u64, space: usize, owner: Pubkey) -> bool {
+        owner.eq(&Pubkey::default()) && lamports == 0 || Rent::default().is_exempt(lamports, space)
     }
 }