Minor ProgramTest improvements (backport #20051) (#20054)

* Add stable_log output when a program is loaded as native code instead of BPF

(cherry picked from commit 34f5020457)

* Add ProgramTest::add_builtin_program()

This permits the unit testing of builtin programs in the ProgramTest environment

(cherry picked from commit 830ca369f1)

Co-authored-by: Michael Vines <mvines@gmail.com>

program-test/src/lib.rs

@@ -103,6 +103,9 @@ pub fn builtin_process_instruction(
 ) -> Result<(), InstructionError> {
     set_invoke_context(invoke_context);
 
+    let logger = invoke_context.get_logger();
+    stable_log::program_invoke(&logger, program_id, invoke_context.invoke_depth());
+
     let keyed_accounts = invoke_context.get_keyed_accounts()?;
 
     // Copy all the accounts into a HashMap to ensure there are no duplicates
@@ -151,7 +154,12 @@ pub fn builtin_process_instruction(
         .collect();
 
     // Execute the program
-    process_instruction(program_id, &account_infos, input).map_err(u64::from)?;
+    process_instruction(program_id, &account_infos, input).map_err(|err| {
+        let err = u64::from(err);
+        stable_log::program_failure(&logger, program_id, &err.into());
+        err
+    })?;
+    stable_log::program_success(&logger, program_id);
 
     // Commit AccountInfo changes back into KeyedAccounts
     for keyed_account in keyed_accounts {
@@ -706,6 +714,20 @@ impl ProgramTest {
         }
     }
 
+    /// Add a builtin program to the test environment.
+    ///
+    /// Note that builtin programs are responsible for their own `stable_log` output.
+    pub fn add_builtin_program(
+        &mut self,
+        program_name: &str,
+        program_id: Pubkey,
+        process_instruction: ProcessInstructionWithContext,
+    ) {
+        info!("\"{}\" builtin program", program_name);
+        self.builtins
+            .push(Builtin::new(program_name, program_id, process_instruction));
+    }
+
     fn setup_bank(
         &self,
     ) -> (