refactor: add function_runner feature flag and CairoFunctionRunner alias

CHANGELOG.md

@@ -12,6 +12,8 @@ Both branches support Stwo prover opcodes (Blake2s, QM31) since v2.0.0.
 
 #### Upcoming Changes
 
+* refactor: add `function_runner` feature flag and `CairoFunctionRunner` type alias for `CairoRunner` [#2377](https://github.com/starkware-libs/cairo-vm/pull/2377)
+
 * Add Stwo cairo runner API [#2351](https://github.com/lambdaclass/cairo-vm/pull/2351)
 
 * Add union merge strategy for CHANGELOG.md [#2345](https://github.com/lambdaclass/cairo-vm/pull/2345)

vm/Cargo.toml

@@ -21,7 +21,8 @@ cairo-0-secp-hints = []
 cairo-0-data-availability-hints = []
 
 # Note that these features are not retro-compatible with the cairo Python VM.
-test_utils = ["dep:arbitrary", "starknet-types-core/arbitrary", "starknet-types-core/std"] # This feature will reference every test-oriented feature
+function_runner = []
+test_utils = ["function_runner", "dep:arbitrary", "starknet-types-core/arbitrary", "starknet-types-core/std"] # This feature will reference every test-oriented feature
 # Allows extending the set of hints for the current vm run from within a hint.
 # For a usage example checkout vm/src/tests/run_deprecated_contract_class_simplified.rs
 extensive_hints = []

vm/src/vm/runners/function_runner.rs

@@ -1,7 +1,7 @@
 //! Function runner extension methods for [`CairoRunner`].
 //!
 //! Provides a simplified API for executing individual Cairo 0 functions by name or PC.
-//! This entire module is compiled only when the `test_utils` feature is enabled.
+//! Enabled by the `function_runner` feature flag.
 
 use crate::hint_processor::builtin_hint_processor::builtin_hint_processor_definition::BuiltinHintProcessor;
 use crate::hint_processor::hint_processor_definition::HintProcessor;
@@ -18,8 +18,11 @@ use crate::vm::errors::vm_exception::VmException;
 use crate::vm::runners::cairo_runner::{CairoArg, CairoRunner, ORDERED_BUILTIN_LIST};
 use crate::vm::security::verify_secure_runner;
 
+/// Type alias for [`CairoRunner`] with testing methods enabled.
+/// Mirrors the Python `CairoFunctionRunner` class interface.
+pub type CairoFunctionRunner = CairoRunner;
+
 /// Identifies a Cairo function entrypoint either by function name or by program counter.
-#[allow(dead_code)]
 pub enum EntryPoint<'a> {
     Name(&'a str),
     Pc(usize),
@@ -75,7 +78,7 @@ impl CairoRunner {
     /// Resolves the entrypoint, builds the call stack, runs until the function's end PC,
     /// and optionally verifies security constraints.
     #[allow(clippy::result_large_err)]
-    pub(crate) fn run_from_entrypoint(
+    pub fn run_from_entrypoint(
         &mut self,
         entrypoint: EntryPoint<'_>,
         args: &[CairoArg],
@@ -106,7 +109,7 @@ impl CairoRunner {
 
     /// Resolves `__main__.<entrypoint>` to its PC, following alias chains.
     #[allow(clippy::result_large_err)]
-    pub(crate) fn get_function_pc(&self, entrypoint: &str) -> Result<usize, CairoRunError> {
+    pub fn get_function_pc(&self, entrypoint: &str) -> Result<usize, CairoRunError> {
         let full_name = format!("__main__.{entrypoint}");
         let identifier = self
             .program

vm/src/vm/runners/mod.rs

@@ -1,5 +1,5 @@
 pub mod builtin_runner;
 pub mod cairo_pie;
 pub mod cairo_runner;
-#[cfg(feature = "test_utils")]
-pub(crate) mod function_runner;
+#[cfg(feature = "function_runner")]
+pub mod function_runner;