add test coverage for zig build CLI and options API

test/standalone.zig

@@ -5,6 +5,17 @@ const tests = @import("tests.zig");
 pub fn addCases(cases: *tests.StandaloneContext) void {
     cases.add("test/standalone/hello_world/hello.zig");
     cases.addC("test/standalone/hello_world/hello_libc.zig");
+
+    cases.addBuildFile("test/standalone/options/build.zig", .{
+        .extra_argv = &.{
+            "-Dbool_true",
+            "-Dbool_false=false",
+            "-Dint=1234",
+            "-De=two",
+            "-Dstring=hello",
+        },
+    });
+
     cases.add("test/standalone/cat/main.zig");
     if (builtin.zig_backend == .stage1) { // https://github.com/ziglang/zig/issues/6025
         cases.add("test/standalone/issue_9693/main.zig");

test/standalone/options/build.zig

@@ -0,0 +1,22 @@
+const std = @import("std");
+
+pub fn build(b: *std.build.Builder) void {
+    const target = b.standardTargetOptions(.{});
+    const mode = b.standardReleaseOptions();
+
+    const main = b.addTest("src/main.zig");
+    main.setTarget(target);
+    main.setBuildMode(mode);
+
+    const options = b.addOptions();
+    main.addOptions("build_options", options);
+    options.addOption(bool, "bool_true", b.option(bool, "bool_true", "t").?);
+    options.addOption(bool, "bool_false", b.option(bool, "bool_false", "f").?);
+    options.addOption(u32, "int", b.option(u32, "int", "i").?);
+    const E = enum { one, two, three };
+    options.addOption(E, "e", b.option(E, "e", "e").?);
+    options.addOption([]const u8, "string", b.option([]const u8, "string", "s").?);
+
+    const test_step = b.step("test", "Run unit tests");
+    test_step.dependOn(&main.step);
+}

test/standalone/options/src/main.zig

@@ -0,0 +1,12 @@
+const std = @import("std");
+const assert = std.debug.assert;
+
+const build_options = @import("build_options");
+
+test "build options" {
+    comptime assert(build_options.bool_true);
+    comptime assert(!build_options.bool_false);
+    comptime assert(build_options.int == 1234);
+    comptime assert(build_options.e == .two);
+    comptime assert(std.mem.eql(u8, build_options.string, "hello"));
+}

test/tests.zig

@@ -1043,6 +1043,7 @@ pub const StandaloneContext = struct {
         requires_stage2: bool = false,
         use_emulation: bool = false,
         requires_symlinks: bool = false,
+        extra_argv: []const []const u8 = &.{},
     }) void {
         const b = self.b;
 
@@ -1063,6 +1064,8 @@ pub const StandaloneContext = struct {
         zig_args.append("--build-file") catch unreachable;
         zig_args.append(b.pathFromRoot(build_file)) catch unreachable;
 
+        zig_args.appendSlice(features.extra_argv) catch unreachable;
+
         zig_args.append("test") catch unreachable;
 
         if (b.verbose) {