Move all settings flags into `//rust/settings` (#2870)

Aliases are still in place for backward compatibility and intended for
public use.

BUILD.bazel

@@ -1,58 +1,36 @@
-load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
-load("@bazel_skylib//rules:common_settings.bzl", "string_flag")
-load(
-    "//rust:defs.bzl",
-    "capture_clippy_output",
-    "clippy_flag",
-    "clippy_flags",
-    "error_format",
-    "extra_exec_rustc_flag",
-    "extra_exec_rustc_flags",
-    "extra_rustc_flag",
-    "extra_rustc_flags",
-    "no_std",
-    "per_crate_rustc_flag",
-    "rustc_output_diagnostics",
-)
-
 exports_files([
+    ".clippy.toml",
+    ".rustfmt.toml",
     "LICENSE",
     "MODULE.bazel",
+    "version.bzl",
 ])
 
-bzl_library(
-    name = "bzl_lib",
-    srcs = [
-        ":version.bzl",
-    ],
-    visibility = ["//visibility:public"],
-)
-
 # This setting may be changed from the command line to generate machine readable errors.
-error_format(
+alias(
     name = "error_format",
-    build_setting_default = "human",
+    actual = "//rust/settings:error_format",
     visibility = ["//visibility:public"],
 )
 
 # This setting may be changed from the command line to generate rustc diagnostics.
-rustc_output_diagnostics(
+alias(
     name = "rustc_output_diagnostics",
-    build_setting_default = False,
+    actual = "//rust/settings:rustc_output_diagnostics",
     visibility = ["//visibility:public"],
 )
 
 # This setting may be used to pass extra options to clippy from the command line.
 # It applies across all targets.
-clippy_flags(
+alias(
     name = "clippy_flags",
-    build_setting_default = [],
+    actual = "//rust/settings:clippy_flags",
     visibility = ["//visibility:public"],
 )
 
-clippy_flag(
+alias(
     name = "clippy_flag",
-    build_setting_default = "",
+    actual = "//rust/settings:clippy_flag",
     visibility = ["//visibility:public"],
 )
 
@@ -60,15 +38,15 @@ clippy_flag(
 # in non-exec configuration.
 # It applies across all targets whereas the rustc_flags option on targets applies only
 # to that target. This can be useful for passing build-wide options such as LTO.
-extra_rustc_flags(
+alias(
     name = "extra_rustc_flags",
-    build_setting_default = [],
+    actual = "//rust/settings:extra_rustc_flags",
     visibility = ["//visibility:public"],
 )
 
-extra_rustc_flag(
+alias(
     name = "extra_rustc_flag",
-    build_setting_default = "",
+    actual = "//rust/settings:extra_rustc_flag",
     visibility = ["//visibility:public"],
 )
 
@@ -76,35 +54,33 @@ extra_rustc_flag(
 # in exec configuration.
 # It applies across all targets whereas the rustc_flags option on targets applies only
 # to that target. This can be useful for passing build-wide options such as LTO.
-extra_exec_rustc_flags(
+alias(
     name = "extra_exec_rustc_flags",
-    build_setting_default = [],
+    actual = "//rust/settings:extra_exec_rustc_flags",
     visibility = ["//visibility:public"],
 )
 
-extra_exec_rustc_flag(
+alias(
     name = "extra_exec_rustc_flag",
-    build_setting_default = "",
+    actual = "//rust/settings:extra_exec_rustc_flag",
     visibility = ["//visibility:public"],
 )
 
-per_crate_rustc_flag(
+alias(
     name = "experimental_per_crate_rustc_flag",
-    build_setting_default = "",
+    actual = "//rust/settings:experimental_per_crate_rustc_flag",
     visibility = ["//visibility:public"],
 )
 
-# This setting is used by the clippy rules. See https://bazelbuild.github.io/rules_rust/rust_clippy.html
-label_flag(
+alias(
     name = "clippy.toml",
-    build_setting_default = "//tools/clippy:clippy.toml",
+    actual = "//rust/settings:clippy.toml",
     visibility = ["//visibility:public"],
 )
 
-# This setting is used by the rustfmt rules. See https://bazelbuild.github.io/rules_rust/rust_fmt.html
-label_flag(
+alias(
     name = "rustfmt.toml",
-    build_setting_default = "//tools/rustfmt:rustfmt.toml",
+    actual = "//rust/settings:rustfmt.toml",
     visibility = ["//visibility:public"],
 )
 
@@ -114,35 +90,20 @@ alias(
     visibility = ["//visibility:public"],
 )
 
-capture_clippy_output(
+alias(
     name = "capture_clippy_output",
-    build_setting_default = False,
+    actual = "//rust/settings:capture_clippy_output",
     visibility = ["//visibility:public"],
 )
 
-# This setting may be used to enable builds without the standard library.
-# Currently only no_std + alloc is supported, which can be enabled with setting the value to "alloc".
-# In the future we could add support for additional modes, e.g "core", "alloc,collections".
-string_flag(
+alias(
     name = "no_std",
-    build_setting_default = "off",
-    values = [
-        "alloc",
-        "off",
-    ],
+    actual = "//rust/settings:no_std",
     visibility = ["//visibility:public"],
 )
 
-# A hack target to allow as to only apply the no_std mode in target config.
-no_std(
-    name = "build_target_in_no_std",
-)
-
-# A config setting for setting conditional `cargo_features`, `deps`, based on the `:no_std` value.
-config_setting(
+alias(
     name = "is_no_std",
-    flag_values = {
-        ":build_target_in_no_std": "alloc",
-    },
+    actual = "//rust/settings:is_no_std",
     visibility = ["//visibility:public"],
 )

docs/BUILD.bazel

@@ -26,7 +26,6 @@ bzl_library(
     name = "all_docs",
     deps = [
         ":docs_deps",
-        "@rules_rust//:bzl_lib",
         "@rules_rust//bindgen:bzl_lib",
         "@rules_rust//cargo:bzl_lib",
         "@rules_rust//crate_universe:bzl_lib",

rust/settings/.clippy.toml

@@ -0,0 +1 @@
+# clippy options: https://rust-lang.github.io/rust-clippy/

rust/settings/BUILD.bazel

@@ -1,13 +1,31 @@
 load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
 load("@bazel_skylib//rules:common_settings.bzl", "bool_flag", "string_flag")
+load(
+    "//rust:defs.bzl",
+    "capture_clippy_output",
+    "clippy_flag",
+    "clippy_flags",
+    "error_format",
+    "extra_exec_rustc_flag",
+    "extra_exec_rustc_flags",
+    "extra_rustc_flag",
+    "extra_rustc_flags",
+    "no_std",
+    "per_crate_rustc_flag",
+    "rustc_output_diagnostics",
+)
 load("//rust/private:unpretty.bzl", "rust_unpretty_flag")
 load(":incompatible.bzl", "incompatible_flag")
 
-package(default_visibility = ["//visibility:public"])
+exports_files([
+    ".clippy.toml",
+    ".rustfmt.toml",
+])
 
 bzl_library(
     name = "bzl_lib",
     srcs = glob(["**/*.bzl"]),
+    visibility = ["//visibility:public"],
 )
 
 rust_unpretty_flag(
@@ -27,6 +45,7 @@ rust_unpretty_flag(
         "mir",
         "normal",
     ],
+    visibility = ["//visibility:public"],
 )
 
 # A flag controlling whether to rename first-party crates such that their names
@@ -37,6 +56,7 @@ rust_unpretty_flag(
 bool_flag(
     name = "rename_first_party_crates",
     build_setting_default = False,
+    visibility = ["//visibility:public"],
 )
 
 # A flag specifying the location of vendored third-party rust crates within this
@@ -46,6 +66,7 @@ bool_flag(
 string_flag(
     name = "third_party_dir",
     build_setting_default = "//third_party/rust",
+    visibility = ["//visibility:public"],
 )
 
 # A flag to control whether rust_library and rust_binary targets should
@@ -53,6 +74,7 @@ string_flag(
 bool_flag(
     name = "use_real_import_macro",
     build_setting_default = False,
+    visibility = ["//visibility:public"],
 )
 
 # When set, this flag causes rustc to emit .rmeta files and use them for rlib -> rlib dependencies.
@@ -61,6 +83,7 @@ bool_flag(
 bool_flag(
     name = "pipelined_compilation",
     build_setting_default = False,
+    visibility = ["//visibility:public"],
 )
 
 # A flag to control whether to link rust_binary and rust_test targets using
@@ -68,6 +91,7 @@ bool_flag(
 bool_flag(
     name = "experimental_use_cc_common_link",
     build_setting_default = False,
+    visibility = ["//visibility:public"],
 )
 
 # A flag to indicate that a global allocator is in use when using --@rules_rust//rust/settings:experimental_use_cc_common_link
@@ -76,6 +100,7 @@ bool_flag(
 bool_flag(
     name = "experimental_use_global_allocator",
     build_setting_default = False,
+    visibility = ["//visibility:public"],
 )
 
 # A flag to have coverage tooling added as `coverage_common.instrumented_files_info.metadata_files` instead of
@@ -83,12 +108,14 @@ bool_flag(
 bool_flag(
     name = "experimental_use_coverage_metadata_files",
     build_setting_default = True,
+    visibility = ["//visibility:public"],
 )
 
 # A flag to set rustc --sysroot flag to the sysroot generated by rust_toolchain.
 bool_flag(
     name = "toolchain_generated_sysroot",
     build_setting_default = True,
+    visibility = ["//visibility:public"],
 )
 
 # A flag to put rust_test compilation outputs in the same directory as the rust_library compilation outputs.
@@ -96,12 +123,14 @@ incompatible_flag(
     name = "incompatible_change_rust_test_compilation_output_directory",
     build_setting_default = False,
     issue = "https://github.com/bazelbuild/rules_rust/issues/2827",
+    visibility = ["//visibility:public"],
 )
 
 # A flag to control whether to link libstd dynamically.
 bool_flag(
     name = "experimental_link_std_dylib",
     build_setting_default = False,
+    visibility = ["//visibility:public"],
 )
 
 # A flag to control whether the shell path from a shell toolchain (`@bazel_tools//tools/sh:toolchain_type`)
@@ -109,4 +138,118 @@ bool_flag(
 bool_flag(
     name = "experimental_use_sh_toolchain_for_bootstrap_process_wrapper",
     build_setting_default = False,
+    visibility = ["//visibility:public"],
+)
+
+# This setting is used by the clippy rules. See https://bazelbuild.github.io/rules_rust/rust_clippy.html
+label_flag(
+    name = "clippy.toml",
+    build_setting_default = ".clippy.toml",
+    visibility = ["//visibility:public"],
+)
+
+# This setting is used by the rustfmt rules. See https://bazelbuild.github.io/rules_rust/rust_fmt.html
+label_flag(
+    name = "rustfmt.toml",
+    build_setting_default = ".rustfmt.toml",
+    visibility = ["//visibility:public"],
+)
+
+capture_clippy_output(
+    name = "capture_clippy_output",
+    build_setting_default = False,
+    visibility = ["//visibility:public"],
+)
+
+# This setting may be used to enable builds without the standard library.
+# Currently only no_std + alloc is supported, which can be enabled with setting the value to "alloc".
+# In the future we could add support for additional modes, e.g "core", "alloc,collections".
+string_flag(
+    name = "no_std",
+    build_setting_default = "off",
+    values = [
+        "alloc",
+        "off",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+# A hack target to allow as to only apply the no_std mode in target config.
+no_std(
+    name = "build_target_in_no_std",
+)
+
+# A config setting for setting conditional `cargo_features`, `deps`, based on the `:no_std` value.
+config_setting(
+    name = "is_no_std",
+    flag_values = {
+        ":build_target_in_no_std": "alloc",
+    },
+    visibility = ["//visibility:public"],
+)
+
+# This setting may be changed from the command line to generate machine readable errors.
+error_format(
+    name = "error_format",
+    build_setting_default = "human",
+    visibility = ["//visibility:public"],
+)
+
+# This setting may be changed from the command line to generate rustc diagnostics.
+rustc_output_diagnostics(
+    name = "rustc_output_diagnostics",
+    build_setting_default = False,
+    visibility = ["//visibility:public"],
+)
+
+# This setting may be used to pass extra options to clippy from the command line.
+# It applies across all targets.
+clippy_flags(
+    name = "clippy_flags",
+    build_setting_default = [],
+    visibility = ["//visibility:public"],
+)
+
+clippy_flag(
+    name = "clippy_flag",
+    build_setting_default = "",
+    visibility = ["//visibility:public"],
+)
+
+# This setting may be used to pass extra options to rustc from the command line
+# in non-exec configuration.
+# It applies across all targets whereas the rustc_flags option on targets applies only
+# to that target. This can be useful for passing build-wide options such as LTO.
+extra_rustc_flags(
+    name = "extra_rustc_flags",
+    build_setting_default = [],
+    visibility = ["//visibility:public"],
+)
+
+extra_rustc_flag(
+    name = "extra_rustc_flag",
+    build_setting_default = "",
+    visibility = ["//visibility:public"],
+)
+
+# This setting may be used to pass extra options to rustc from the command line
+# in exec configuration.
+# It applies across all targets whereas the rustc_flags option on targets applies only
+# to that target. This can be useful for passing build-wide options such as LTO.
+extra_exec_rustc_flags(
+    name = "extra_exec_rustc_flags",
+    build_setting_default = [],
+    visibility = ["//visibility:public"],
+)
+
+extra_exec_rustc_flag(
+    name = "extra_exec_rustc_flag",
+    build_setting_default = "",
+    visibility = ["//visibility:public"],
+)
+
+per_crate_rustc_flag(
+    name = "experimental_per_crate_rustc_flag",
+    build_setting_default = "",
+    visibility = ["//visibility:public"],
 )