Remove incompatible_test_attr_crate_and_srcs_mutually_exclusive (#2641

)

closes #2324

rust/private/rust.bzl

@@ -300,11 +300,10 @@ def _rust_test_impl(ctx):
     deps = transform_deps(ctx.attr.deps)
     proc_macro_deps = transform_deps(ctx.attr.proc_macro_deps + get_import_macro_deps(ctx))
 
-    if toolchain._incompatible_test_attr_crate_and_srcs_mutually_exclusive:
-        if ctx.attr.crate and ctx.attr.srcs:
-            fail("rust_test.crate and rust_test.srcs are mutually exclusive. Update {} to use only one of these attributes".format(
-                ctx.label,
-            ))
+    if ctx.attr.crate and ctx.attr.srcs:
+        fail("rust_test.crate and rust_test.srcs are mutually exclusive. Update {} to use only one of these attributes".format(
+            ctx.label,
+        ))
 
     if ctx.attr.crate:
         # Target is building the crate in `test` config

rust/settings/BUILD.bazel

@@ -92,13 +92,6 @@ incompatible_flag(
     issue = "https://github.com/bazelbuild/rules_rust/issues/2039",
 )
 
-# A flag to make `rust_test.crate` and `rust_test.srcs` mutually exclusive.
-incompatible_flag(
-    name = "incompatible_test_attr_crate_and_srcs_mutually_exclusive",
-    build_setting_default = True,
-    issue = "https://github.com/bazelbuild/rules_rust/issues/2324",
-)
-
 # A flag to control whether to link libstd dynamically.
 bool_flag(
     name = "experimental_link_std_dylib",

rust/toolchain.bzl

@@ -673,7 +673,6 @@ def _rust_toolchain_impl(ctx):
         _experimental_use_coverage_metadata_files = ctx.attr._experimental_use_coverage_metadata_files[BuildSettingInfo].value,
         _experimental_toolchain_generated_sysroot = ctx.attr._experimental_toolchain_generated_sysroot[IncompatibleFlagInfo].enabled,
         _incompatible_no_rustc_sysroot_env = ctx.attr._incompatible_no_rustc_sysroot_env[IncompatibleFlagInfo].enabled,
-        _incompatible_test_attr_crate_and_srcs_mutually_exclusive = ctx.attr._incompatible_test_attr_crate_and_srcs_mutually_exclusive[IncompatibleFlagInfo].enabled,
         _no_std = no_std,
     )
     return [
@@ -863,9 +862,6 @@ rust_toolchain = rule(
         "_incompatible_no_rustc_sysroot_env": attr.label(
             default = Label("//rust/settings:incompatible_no_rustc_sysroot_env"),
         ),
-        "_incompatible_test_attr_crate_and_srcs_mutually_exclusive": attr.label(
-            default = Label("//rust/settings:incompatible_test_attr_crate_and_srcs_mutually_exclusive"),
-        ),
         "_no_std": attr.label(
             default = Label("//:no_std"),
         ),