[framework] Add native function to check protocol feature flags in Move

Adds sui::protocol_config::is_feature_enabled() to allow Move code to query
protocol feature flags at runtime. This enables conditional logic and fallbacks
based on protocol version capabilities.

Author: lxfind

crates/sui-framework/docs/sui/protocol_config.md

@@ -0,0 +1,82 @@
+---
+title: Module `sui::protocol_config`
+---
+
+This module provides access to protocol configuration feature flags.
+Feature flags control the availability of various protocol features and
+are enabled/disabled at specific protocol versions during epoch changes.
+
+
+-  [Function `is_feature_enabled`](#sui_protocol_config_is_feature_enabled)
+    -  [Arguments](#@Arguments_0)
+    -  [Returns](#@Returns_1)
+    -  [Aborts](#@Aborts_2)
+    -  [Example (for framework use only)](#@Example_(for_framework_use_only)_3)
+
+
+<pre><code></code></pre>
+
+
+
+<a name="sui_protocol_config_is_feature_enabled"></a>
+
+## Function `is_feature_enabled`
+
+Checks if a specific protocol feature flag is enabled.
+
+Restricted to internal use within the sui-framework package only.
+If we need to use it in sui-system, we can add friend declarations.
+We should never need to expose this to user packages.
+
+
+<a name="@Arguments_0"></a>
+
+### Arguments
+
+* <code>feature_flag_name</code> - The name of the feature flag as bytes (e.g., b"enable_vdf")
+
+
+<a name="@Returns_1"></a>
+
+### Returns
+
+* <code><b>true</b></code> if the feature is enabled in the current protocol version
+* <code><b>false</b></code> if the feature is disabled
+
+
+<a name="@Aborts_2"></a>
+
+### Aborts
+
+* Error code 0: Feature flag name not found
+* Error code 1: Invalid feature flag name (not valid UTF-8)
+
+
+<a name="@Example_(for_framework_use_only)_3"></a>
+
+### Example (for framework use only)
+
+```move
+use sui::protocol_config;
+
+if (protocol_config::is_feature_enabled(b"enable_accumulators")) {
+// Accumulators are available
+};
+```
+
+
+<pre><code><b>public</b>(<a href="../sui/package.md#sui_package">package</a>) <b>fun</b> <a href="../sui/protocol_config.md#sui_protocol_config_is_feature_enabled">is_feature_enabled</a>(feature_flag_name: &vector&lt;u8&gt;): bool
+</code></pre>
+
+
+
+<details>
+<summary>Implementation</summary>
+
+
+<pre><code><b>public</b>(<a href="../sui/package.md#sui_package">package</a>) <b>native</b> <b>fun</b> <a href="../sui/protocol_config.md#sui_protocol_config_is_feature_enabled">is_feature_enabled</a>(feature_flag_name: &vector&lt;u8&gt;): bool;
+</code></pre>
+
+
+
+</details>

crates/sui-framework/packages/sui-framework/sources/protocol_config.move

@@ -0,0 +1,35 @@
+// Copyright (c) Mysten Labs, Inc.
+// SPDX-License-Identifier: Apache-2.0
+
+/// This module provides access to protocol configuration feature flags.
+/// Feature flags control the availability of various protocol features and
+/// are enabled/disabled at specific protocol versions during epoch changes.
+
+module sui::protocol_config;
+
+/// Checks if a specific protocol feature flag is enabled.
+///
+/// Restricted to internal use within the sui-framework package only.
+/// If we need to use it in sui-system, we can add friend declarations.
+/// We should never need to expose this to user packages.
+///
+/// # Arguments
+/// * `feature_flag_name` - The name of the feature flag as bytes (e.g., b"enable_vdf")
+///
+/// # Returns
+/// * `true` if the feature is enabled in the current protocol version
+/// * `false` if the feature is disabled
+///
+/// # Aborts
+/// * Error code 0: Feature flag name not found
+/// * Error code 1: Invalid feature flag name (not valid UTF-8)
+///
+/// # Example (for framework use only)
+/// ```move
+/// use sui::protocol_config;
+///
+/// if (protocol_config::is_feature_enabled(b"enable_accumulators")) {
+///     // Accumulators are available
+/// };
+/// ```
+public(package) native fun is_feature_enabled(feature_flag_name: &vector<u8>): bool;

crates/sui-framework/packages/sui-framework/tests/protocol_config_tests.move

@@ -0,0 +1,33 @@
+// Copyright (c) Mysten Labs, Inc.
+// SPDX-License-Identifier: Apache-2.0
+
+#[test_only]
+module sui::protocol_config_tests;
+
+use sui::protocol_config;
+
+#[test]
+fun test_is_feature_enabled_true() {
+    let is_enabled = protocol_config::is_feature_enabled(b"advance_epoch_start_time_in_safe_mode");
+    assert!(is_enabled, 1);
+}
+
+#[test]
+fun test_is_feature_enabled_false() {
+    let is_enabled = protocol_config::is_feature_enabled(b"per_command_shared_object_transfer_rules");
+    assert!(!is_enabled, 1);
+}
+
+#[test]
+#[expected_failure(abort_code = 0)]
+fun test_is_feature_enabled_invalid_flag() {
+    protocol_config::is_feature_enabled(b"nonexistent_feature_flag_xyz");
+}
+
+#[test]
+#[expected_failure(abort_code = 1)]
+fun test_is_feature_enabled_invalid_utf8() {
+    // Invalid UTF-8 sequence: 0xFF is not valid UTF-8
+    let invalid_utf8 = vector[0xFF, 0xFE, 0xFD];
+    protocol_config::is_feature_enabled(&invalid_utf8);
+}

crates/sui-framework/packages_compiled/sui-framework

@@ -1105,6 +1105,9 @@ ecvrf_verify
 ed25519_verify
 	public fun
 	0x2::ed25519
+is_feature_enabled
+	public(package) fun
+	0x2::protocol_config
 hash_to_input
 	public fun
 	0x2::vdf

crates/sui-framework/published_api.txt

@@ -82,6 +82,7 @@ pub mod event;
 mod funds_accumulator;
 mod object;
 pub mod object_runtime;
+mod protocol_config;
 mod random;
 pub mod test_scenario;
 mod test_utils;
@@ -1245,6 +1246,11 @@ pub fn all_natives(silent: bool, protocol_config: &ProtocolConfig) -> NativeFunc
             "poseidon_bn254_internal",
             make_native!(poseidon::poseidon_bn254_internal),
         ),
+        (
+            "protocol_config",
+            "is_feature_enabled",
+            make_native!(protocol_config::is_feature_enabled),
+        ),
         (
             "vdf",
             "vdf_verify_internal",

sui-execution/latest/sui-move-natives/src/lib.rs

@@ -0,0 +1,73 @@
+// Copyright (c) Mysten Labs, Inc.
+// SPDX-License-Identifier: Apache-2.0
+
+use crate::get_extension;
+use crate::object_runtime::ObjectRuntime;
+use move_binary_format::errors::PartialVMResult;
+use move_vm_runtime::native_functions::NativeContext;
+use move_vm_types::{
+    loaded_data::runtime_types::Type,
+    natives::function::NativeResult,
+    pop_arg,
+    values::{Value, VectorRef},
+};
+use smallvec::smallvec;
+use std::collections::VecDeque;
+
+pub const FEATURE_FLAG_NOT_FOUND_ERROR: u64 = 0;
+pub const INVALID_FEATURE_FLAG_NAME_ERROR: u64 = 1;
+
+/***************************************************************************************************
+ * native fun is_feature_enabled
+ *
+ * Implementation of the Move native function `protocol_config::is_feature_enabled(
+ *      feature_flag_name: &vector<u8>): bool`
+ *
+ * Checks if a protocol feature flag is enabled in the current protocol version.
+ * Takes raw bytes for simplicity since this is internal framework use only.
+ *
+ * Gas cost: 0 (zero cost for framework-internal use)
+ **************************************************************************************************/
+pub fn is_feature_enabled(
+    context: &mut NativeContext,
+    ty_args: Vec<Type>,
+    mut args: VecDeque<Value>,
+) -> PartialVMResult<NativeResult> {
+    debug_assert!(ty_args.is_empty());
+    debug_assert!(args.len() == 1);
+
+    // Get the bytes directly - Move passes raw vector<u8>
+    let feature_flag_name_bytes = pop_arg!(args, VectorRef);
+    let bytes = feature_flag_name_bytes.as_bytes_ref();
+
+    // Validate that the feature flag name is valid UTF-8
+    let feature_flag_name = match String::from_utf8(bytes.to_vec()) {
+        Ok(s) => s,
+        Err(_) => {
+            // Invalid UTF-8 in feature flag name - abort with error
+            return Ok(NativeResult::err(
+                context.gas_used(),
+                INVALID_FEATURE_FLAG_NAME_ERROR,
+            ));
+        }
+    };
+
+    let protocol_config = &get_extension!(context, ObjectRuntime)?.protocol_config;
+
+    // Use the auto-generated lookup_feature method to find the feature flag
+    let is_enabled = match protocol_config.lookup_feature(feature_flag_name) {
+        Some(value) => value,
+        None => {
+            // Feature flag not found - abort with error
+            return Ok(NativeResult::err(
+                context.gas_used(),
+                FEATURE_FLAG_NOT_FOUND_ERROR,
+            ));
+        }
+    };
+
+    Ok(NativeResult::ok(
+        context.gas_used(),
+        smallvec![Value::bool(is_enabled)],
+    ))
+}