tests: current context switching

crates/evm/src/machine.cairo

@@ -67,7 +67,7 @@ impl MachineCurrentContextImpl of MachineCurrentContextTrait {
     /// to divide a unique Stack/Memory simulated by a dict into
     /// multiple sub-structures relative to a single context.
     #[inline(always)]
-    fn set_active_execution_ctx(ref self: Machine, ctx: ExecutionContext) {
+    fn set_current_context(ref self: Machine, ctx: ExecutionContext) {
         self.memory.set_active_segment(ctx.id);
         self.stack.set_active_segment(ctx.id);
         self.current_context = BoxTrait::new(ctx);

crates/evm/src/tests/test_machine.cairo

@@ -1,7 +1,8 @@
 use evm::context::CallContextTrait;
 use evm::machine::{Machine, MachineCurrentContextTrait};
 use evm::tests::test_utils::{
-    evm_address, setup_machine_with_bytecode, setup_machine, starknet_address
+    evm_address, setup_machine_with_bytecode, setup_machine, starknet_address,
+    setup_execution_context
 };
 
 
@@ -16,6 +17,28 @@ fn test_machine_default() {
     assert(!machine.stopped(), 'ctx should not be stopped');
 }
 
+#[test]
+#[available_gas(20000000)]
+fn test_set_current_context() {
+    let mut machine: Machine = Default::default();
+
+    let first_ctx = machine.current_context.unbox();
+    assert(first_ctx.id == 0, 'wrong first id');
+    // We need to re-box the context into the machine, otherwise we have a "Variable Moved" error.
+    machine.current_context = BoxTrait::new(first_ctx);
+    assert(machine.stack.active_segment == 0, 'wrong initial stack segment');
+    assert(machine.memory.active_segment == 0, 'wrong initial memory segment');
+
+    // Create another context with id=1
+    let mut second_ctx = setup_execution_context();
+    second_ctx.id = 1;
+
+    machine.set_current_context(second_ctx);
+    assert(machine.stack.active_segment == 1, 'wrong updated stack segment');
+    assert(machine.memory.active_segment == 1, 'wrong updated stack segment');
+    assert(machine.current_context.unbox().id == 1, 'wrong updated id');
+}
+
 #[test]
 #[available_gas(20000000)]
 fn test_set_pc() {