feat: support Zig build modes

.bazelrc

@@ -2,6 +2,8 @@
 # Take care to document any settings that you expect users to apply.
 # Settings that apply only to CI are in .github/workflows/ci.bazelrc
 
+import %workspace%/.bazelrc.flags
+
 # Deleted packages for integration tests.
 # To update these lines, execute
 # `bazel run @contrib_rules_bazel_integration_test//tools:update_deleted_packages`

.bazelrc.flags

@@ -0,0 +1,6 @@
+# Defines aliases for rules_zig build settings flags,
+# see https://bazel.build/extending/config#using-build-setting-aliases
+# Copy this file into your project and import it into your `.bazelrc` to enable
+# the same aliases.
+
+build --flag_alias=zig_mode=@rules_zig//zig/settings:mode

util/update_filegroups.py

@@ -15,7 +15,7 @@
 import subprocess
 
 # Add exlusions for packages to skip here.
-PACKAGE_PATTERN =  "//... - //docs/... - //util/... - //zig/tests/..."
+PACKAGE_PATTERN =  "//...:* - //docs/...:* - //util/...:* - //zig/tests/...:*"
 
 # Add extra source files to capture here.
 EXTRA_SRCS = {

zig/BUILD.bazel

@@ -58,7 +58,9 @@ filegroup(
         ":defs.bzl",
         ":repositories.bzl",
         ":toolchain.bzl",
+        "//zig/config:all_files",
         "//zig/private:all_files",
+        "//zig/settings:all_files",
     ],
     visibility = ["//:__pkg__"],
 )

zig/config/BUILD.bazel

@@ -0,0 +1,9 @@
+# Execute `bazel run //util:update_filegroups` to update this target.
+filegroup(
+    name = "all_files",
+    srcs = [
+        ":BUILD.bazel",
+        "//zig/config/mode:all_files",
+    ],
+    visibility = ["//zig:__pkg__"],
+)

zig/config/mode/BUILD.bazel

@@ -0,0 +1,34 @@
+config_setting(
+    name = "debug",
+    flag_values = {
+        "//zig/settings:mode": "debug",
+    },
+)
+
+config_setting(
+    name = "release_safe",
+    flag_values = {
+        "//zig/settings:mode": "release_safe",
+    },
+)
+
+config_setting(
+    name = "release_small",
+    flag_values = {
+        "//zig/settings:mode": "release_small",
+    },
+)
+
+config_setting(
+    name = "release_fast",
+    flag_values = {
+        "//zig/settings:mode": "release_fast",
+    },
+)
+
+# Execute `bazel run //util:update_filegroups` to update this target.
+filegroup(
+    name = "all_files",
+    srcs = [":BUILD.bazel"],
+    visibility = ["//zig/config:__pkg__"],
+)

zig/private/BUILD.bazel

@@ -1,46 +1,50 @@
 load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
 
 bzl_library(
-    name = "zig_binary",
-    srcs = ["zig_binary.bzl"],
+    name = "zig_package",
+    srcs = ["zig_package.bzl"],
     visibility = ["//zig:__subpackages__"],
     deps = [
         "//zig/private/common:filetypes",
-        "//zig/private/common:zig_cache",
         "//zig/private/providers:zig_package_info",
     ],
 )
 
 bzl_library(
-    name = "zig_package",
-    srcs = ["zig_package.bzl"],
+    name = "zig_test",
+    # Gazelle removes the srcs attribute for some reason.
+    srcs = ["zig_test.bzl"],  # keep
     visibility = ["//zig:__subpackages__"],
-    deps = [
-        "//zig/private/common:filetypes",
-        "//zig/private/providers:zig_package_info",
-    ],
 )
 
 bzl_library(
-    name = "zig_library",
-    srcs = ["zig_library.bzl"],
+    name = "settings",
+    srcs = ["settings.bzl"],
+    visibility = ["//zig:__subpackages__"],
+    deps = ["@bazel_skylib//rules:common_settings"],
+)
+
+bzl_library(
+    name = "zig_binary",
+    srcs = ["zig_binary.bzl"],
     visibility = ["//zig:__subpackages__"],
     deps = [
         "//zig/private/common:filetypes",
         "//zig/private/common:zig_cache",
         "//zig/private/providers:zig_package_info",
+        "//zig/private/providers:zig_settings_info",
     ],
 )
 
 bzl_library(
-    name = "zig_test",
-    # Gazelle removes the srcs attribute for some reason.
-    srcs = ["zig_test.bzl"],  # keep
+    name = "zig_library",
+    srcs = ["zig_library.bzl"],
     visibility = ["//zig:__subpackages__"],
     deps = [
         "//zig/private/common:filetypes",
         "//zig/private/common:zig_cache",
         "//zig/private/providers:zig_package_info",
+        "//zig/private/providers:zig_settings_info",
     ],
 )
 
@@ -68,6 +72,7 @@ filegroup(
     srcs = [
         ":BUILD.bazel",
         ":resolved_toolchain.bzl",
+        ":settings.bzl",
         ":toolchains_repo.bzl",
         ":versions.bzl",
         ":zig_binary.bzl",

zig/private/providers/BUILD.bazel

@@ -6,12 +6,19 @@ bzl_library(
     visibility = ["//zig:__subpackages__"],
 )
 
+bzl_library(
+    name = "zig_settings_info",
+    srcs = ["zig_settings_info.bzl"],
+    visibility = ["//zig:__subpackages__"],
+)
+
 # Execute `bazel run //util:update_filegroups` to update this target.
 filegroup(
     name = "all_files",
     srcs = [
         ":BUILD.bazel",
         ":zig_package_info.bzl",
+        ":zig_settings_info.bzl",
     ],
     visibility = ["//zig/private:__pkg__"],
 )

zig/private/providers/zig_settings_info.bzl

@@ -0,0 +1,18 @@
+"""Defines providers for the settings rule."""
+
+ZigSettingsInfo = provider(
+    doc = "Collection of all active Zig build settings.",
+    fields = {
+        "mode": "The Zig build mode.",
+        "args": "The collected compiler arguments for all active settings.",
+    },
+)
+
+def zig_settings(*, settings, args):
+    """Set flags for the given Zig build settings.
+
+    Args:
+      settings: ZigSettingsInfo, The active Zig build settings.
+      args: Args; mutable, Append the needed Zig compiler flags to this object.
+    """
+    args.add_all(settings.args)

zig/private/settings.bzl

@@ -0,0 +1,50 @@
+"""Implementation of the settings rule."""
+
+load("@bazel_skylib//rules:common_settings.bzl", "BuildSettingInfo")
+load("//zig/private/providers:zig_settings_info.bzl", "ZigSettingsInfo")
+
+DOC = """\
+"""
+
+ATTRS = {
+    "mode": attr.label(
+        doc = "The build mode setting.",
+        mandatory = True,
+    ),
+}
+
+MODE_ARGS = {
+    "debug": ["-O", "Debug"],
+    "release_safe": ["-O", "ReleaseSafe"],
+    "release_small": ["-O", "ReleaseSmall"],
+    "release_fast": ["-O", "ReleaseFast"],
+}
+
+def _settings_impl(ctx):
+    args = []
+
+    mode = ctx.attr.mode[BuildSettingInfo].value
+    args.extend(MODE_ARGS[mode])
+
+    settings_info = ZigSettingsInfo(
+        mode = mode,
+        args = args,
+    )
+
+    settings_json = ctx.actions.declare_file(ctx.label.name + ".json")
+    ctx.actions.write(settings_json, settings_info.to_json(), is_executable = False)
+
+    default_info = DefaultInfo(
+        files = depset([settings_json]),
+    )
+
+    return [
+        default_info,
+        settings_info,
+    ]
+
+settings = rule(
+    _settings_impl,
+    attrs = ATTRS,
+    doc = DOC,
+)

zig/private/zig_binary.bzl

@@ -7,6 +7,11 @@ load(
     "ZigPackageInfo",
     "zig_package_dependencies",
 )
+load(
+    "//zig/private/providers:zig_settings_info.bzl",
+    "ZigSettingsInfo",
+    "zig_settings",
+)
 
 DOC = """\
 """
@@ -27,6 +32,11 @@ ATTRS = {
         mandatory = False,
         providers = [ZigPackageInfo],
     ),
+    "_settings": attr.label(
+        default = "//zig/settings",
+        doc = "Zig build settings.",
+        providers = [ZigSettingsInfo],
+    ),
 }
 
 def _zig_binary_impl(ctx):
@@ -62,6 +72,11 @@ def _zig_binary_impl(ctx):
         args = args,
     )
 
+    zig_settings(
+        settings = ctx.attr._settings[ZigSettingsInfo],
+        args = args,
+    )
+
     ctx.actions.run(
         outputs = outputs,
         inputs = depset(direct = direct_inputs, transitive = transitive_inputs),

zig/private/zig_library.bzl

@@ -7,6 +7,11 @@ load(
     "ZigPackageInfo",
     "zig_package_dependencies",
 )
+load(
+    "//zig/private/providers:zig_settings_info.bzl",
+    "ZigSettingsInfo",
+    "zig_settings",
+)
 
 DOC = """\
 """
@@ -27,6 +32,11 @@ ATTRS = {
         mandatory = False,
         providers = [ZigPackageInfo],
     ),
+    "_settings": attr.label(
+        default = "//zig/settings",
+        doc = "Zig build settings.",
+        providers = [ZigSettingsInfo],
+    ),
 }
 
 def _zig_library_impl(ctx):
@@ -63,6 +73,11 @@ def _zig_library_impl(ctx):
         args = args,
     )
 
+    zig_settings(
+        settings = ctx.attr._settings[ZigSettingsInfo],
+        args = args,
+    )
+
     ctx.actions.run(
         outputs = outputs,
         inputs = depset(direct = direct_inputs, transitive = transitive_inputs),

zig/private/zig_test.bzl

@@ -7,6 +7,11 @@ load(
     "ZigPackageInfo",
     "zig_package_dependencies",
 )
+load(
+    "//zig/private/providers:zig_settings_info.bzl",
+    "ZigSettingsInfo",
+    "zig_settings",
+)
 
 DOC = """\
 """
@@ -27,6 +32,11 @@ ATTRS = {
         mandatory = False,
         providers = [ZigPackageInfo],
     ),
+    "_settings": attr.label(
+        default = "//zig/settings",
+        doc = "Zig build settings.",
+        providers = [ZigSettingsInfo],
+    ),
 }
 
 def _zig_test_impl(ctx):
@@ -62,6 +72,11 @@ def _zig_test_impl(ctx):
         args = args,
     )
 
+    zig_settings(
+        settings = ctx.attr._settings[ZigSettingsInfo],
+        args = args,
+    )
+
     ctx.actions.run(
         outputs = outputs,
         inputs = depset(direct = direct_inputs, transitive = transitive_inputs),

zig/settings/BUILD.bazel

@@ -0,0 +1,26 @@
+load("@bazel_skylib//rules:common_settings.bzl", "string_flag")
+load("//zig/private:settings.bzl", "settings")
+
+settings(
+    name = "settings",
+    mode = ":mode",
+    visibility = ["//visibility:public"],
+)
+
+string_flag(
+    name = "mode",
+    build_setting_default = "debug",
+    values = [
+        "debug",
+        "release_safe",
+        "release_small",
+        "release_fast",
+    ],
+)
+
+# Execute `bazel run //util:update_filegroups` to update this target.
+filegroup(
+    name = "all_files",
+    srcs = [":BUILD.bazel"],
+    visibility = ["//zig:__pkg__"],
+)

zig/tests/BUILD.bazel

@@ -1,9 +1,12 @@
-load(":rules_test.bzl", "rules_test_suite")
+load(":mode_test.bzl", "mode_test_suite")
 load(":package_info_test.bzl", "package_info_test_suite")
+load(":rules_test.bzl", "rules_test_suite")
 load(":versions_test.bzl", "versions_test_suite")
 
-rules_test_suite(name = "rules_test")
+mode_test_suite(name = "mode_test")
 
 package_info_test_suite(name = "package_info_test")
 
+rules_test_suite(name = "rules_test")
+
 versions_test_suite(name = "versions_test")