feat(build): graduate Rust cargo-lambda support from experimental (#8526)

* feat(build): graduate Rust cargo-lambda support from experimental

Remove the experimental/beta flag requirement for building Rust functions
with the rust-cargolambda build method. Users no longer need to pass
--beta-features or set SAM_CLI_BETA_RUST_CARGO_LAMBDA=1 to build Rust
Lambda functions.

Changes:
- Remove RustCargoLambda from ExperimentalFlag class
- Remove _check_rust_cargo_experimental_flag() method from BuildContext
- Update integration tests to not require beta_features flag
- Update unit tests to remove mock for deleted method

* fix: update unit tests for experimental

* feat: move Rust Cargo Lambda out of experimental

- Add CargoLambda to ExperimentalFlag with persistent=True
- Update is_experimental_enabled() to always return True for persistent flags
- Update unit tests for new flag count and persistent behavior

Author: bnusunny

samcli/commands/_utils/experimental.py

@@ -54,7 +54,6 @@ class ExperimentalFlag:
             "experimentalTerraformSupport", EXPERIMENTAL_ENV_VAR_PREFIX + "TERRAFORM_SUPPORT"
         )
     }
-    RustCargoLambda = ExperimentalEntry("experimentalCargoLambda", EXPERIMENTAL_ENV_VAR_PREFIX + "RUST_CARGO_LAMBDA")
     UvPackageManager = ExperimentalEntry(
         "experimentalUvPackageManager", EXPERIMENTAL_ENV_VAR_PREFIX + "UV_PACKAGE_MANAGER"
     )

samcli/commands/build/build_context.py

@@ -706,7 +706,6 @@ def _check_build_method_experimental_flag(self) -> None:
         Prints warning message and confirms if user wants to use beta feature
         """
         EXPERIMENTAL_BUILD_METHODS = {
-            "rust-cargolambda": ExperimentalFlag.RustCargoLambda,
             "python-uv": ExperimentalFlag.UvPackageManager,
         }
 

tests/integration/buildcmd/build_integ_base.py

@@ -1159,7 +1159,7 @@ def _test_with_rust_cargo_lambda(
         overrides = self.get_override(runtime, code_uri, architecture, handler)
         if binary:
             overrides["Binary"] = binary
-        cmdlist = self.get_command_list(use_container=use_container, parameter_overrides=overrides, beta_features=True)
+        cmdlist = self.get_command_list(use_container=use_container, parameter_overrides=overrides)
 
         newenv = os.environ.copy()
         if build_mode:

tests/unit/commands/_utils/test_experimental.py

@@ -57,16 +57,16 @@ def test_set_experimental(self):
         self.gc_mock.return_value.set_value.assert_called_once_with(config_entry, False, is_flag=True, flush=False)
 
     def test_get_all_experimental(self):
-        self.assertEqual(len(get_all_experimental()), 6)
+        self.assertEqual(len(get_all_experimental()), 5)
 
     def test_get_all_experimental_statues(self):
-        self.assertEqual(len(get_all_experimental_statues()), 6)
+        self.assertEqual(len(get_all_experimental_statues()), 5)
 
     def test_get_all_experimental_env_vars(self):
-        self.assertEqual(len(get_all_experimental_env_vars()), 6)
+        self.assertEqual(len(get_all_experimental_env_vars()), 5)
 
     def test_get_enabled_experimental_flags(self):
-        self.assertEqual(len(get_enabled_experimental_flags()), 6)
+        self.assertEqual(len(get_enabled_experimental_flags()), 5)
 
     @patch("samcli.commands._utils.experimental.set_experimental")
     @patch("samcli.commands._utils.experimental.get_all_experimental")

tests/unit/commands/buildcmd/test_build_context.py

@@ -1266,7 +1266,7 @@ def test_build_in_source_event_sent(
         self,
         mock_track_event,
         mock_builder,
-        mock_rust,
+        mock_experimental,
         mock_warning,
         mock_get_resources,
         mock_is_sam_template,