Merge pull request #11633 from SpexGuy

Remove `std.testing.zig_exe_path` in favor of `ZIG_EXE` environment variable

build.zig

@@ -40,7 +40,7 @@ pub fn build(b: *Builder) !void {
     const docs_step = b.step("docs", "Build documentation");
     docs_step.dependOn(&docgen_cmd.step);
 
-    var test_cases = b.addTest("src/test.zig");
+    const test_cases = b.addTest("src/test.zig");
     test_cases.stack_size = stack_size;
     test_cases.setBuildMode(mode);
     test_cases.addPackagePath("test_cases", "test/cases.zig");

lib/std/process.zig

@@ -822,7 +822,6 @@ test "args iterator" {
     const given_suffix = std.fs.path.basename(prog_name);
 
     try testing.expect(mem.eql(u8, expected_suffix, given_suffix));
-    try testing.expect(it.skip()); // Skip over zig_exe_path, passed to the test runner
     try testing.expect(it.next() == null);
     try testing.expect(!it.skip());
 }

lib/std/testing.zig

@@ -22,10 +22,6 @@ pub var base_allocator_instance = std.heap.FixedBufferAllocator.init("");
 /// TODO https://github.com/ziglang/zig/issues/5738
 pub var log_level = std.log.Level.warn;
 
-/// This is available to any test that wants to execute Zig in a child process.
-/// It will be the same executable that is running `zig test`.
-pub var zig_exe_path: []const u8 = undefined;
-
 /// This function is intended to be used only in tests. It prints diagnostics to stderr
 /// and then returns a test failure error when actual_error_union is not expected_error.
 pub fn expectError(expected_error: anyerror, actual_error_union: anytype) !void {

lib/test_runner.zig

@@ -6,29 +6,12 @@ pub const io_mode: io.Mode = builtin.test_io_mode;
 
 var log_err_count: usize = 0;
 
-var args_buffer: [std.fs.MAX_PATH_BYTES + std.mem.page_size]u8 = undefined;
-var args_allocator = std.heap.FixedBufferAllocator.init(&args_buffer);
-
-fn processArgs() void {
-    const args = std.process.argsAlloc(args_allocator.allocator()) catch {
-        @panic("Too many bytes passed over the CLI to the test runner");
-    };
-    if (args.len != 2) {
-        const self_name = if (args.len >= 1) args[0] else if (builtin.os.tag == .windows) "test.exe" else "test";
-        const zig_ext = if (builtin.os.tag == .windows) ".exe" else "";
-        std.debug.print("Usage: {s} path/to/zig{s}\n", .{ self_name, zig_ext });
-        @panic("Wrong number of command line arguments");
-    }
-    std.testing.zig_exe_path = args[1];
-}
-
 pub fn main() void {
     if (builtin.zig_backend != .stage1 and
         (builtin.zig_backend != .stage2_llvm or builtin.cpu.arch == .wasm32))
     {
         return main2() catch @panic("test failure");
     }
-    processArgs();
     const test_fn_list = builtin.test_functions;
     var ok_count: usize = 0;
     var skip_count: usize = 0;

src/main.zig

@@ -3253,40 +3253,29 @@ fn runOrTest(
     defer argv.deinit();
 
     if (test_exec_args.len == 0) {
-        // when testing pass the zig_exe_path to argv
-        if (arg_mode == .zig_test)
-            try argv.appendSlice(&[_][]const u8{
-                exe_path, self_exe_path,
-            })
-            // when running just pass the current exe
-        else
-            try argv.appendSlice(&[_][]const u8{
-                exe_path,
-            });
+        try argv.append(exe_path);
     } else {
         for (test_exec_args) |arg| {
-            if (arg) |a| {
-                try argv.append(a);
-            } else {
-                try argv.appendSlice(&[_][]const u8{
-                    exe_path, self_exe_path,
-                });
-            }
+            try argv.append(arg orelse exe_path);
         }
     }
     if (runtime_args_start) |i| {
         try argv.appendSlice(all_args[i..]);
     }
+    var env_map = try std.process.getEnvMap(arena);
+    try env_map.put("ZIG_EXE", self_exe_path);
+
     // We do not execve for tests because if the test fails we want to print
     // the error message and invocation below.
     if (std.process.can_execv and arg_mode == .run and !watch) {
         // execv releases the locks; no need to destroy the Compilation here.
-        const err = std.process.execv(gpa, argv.items);
+        const err = std.process.execve(gpa, argv.items, &env_map);
         try warnAboutForeignBinaries(arena, arg_mode, target_info, link_libc);
         const cmd = try std.mem.join(arena, " ", argv.items);
         fatal("the following command failed to execve with '{s}':\n{s}", .{ @errorName(err), cmd });
     } else if (std.process.can_spawn) {
         var child = std.ChildProcess.init(argv.items, gpa);
+        child.env_map = &env_map;
         child.stdin_behavior = .Inherit;
         child.stdout_behavior = .Inherit;
         child.stderr_behavior = .Inherit;

src/test.zig

@@ -1214,6 +1214,7 @@ pub const TestContext = struct {
 
     fn run(self: *TestContext) !void {
         const host = try std.zig.system.NativeTargetInfo.detect(.{});
+        const zig_exe_path = try std.process.getEnvVarOwned(self.arena, "ZIG_EXE");
 
         var progress = std.Progress{};
         const root_node = progress.start("compiler", self.cases.items.len);
@@ -1272,6 +1273,7 @@ pub const TestContext = struct {
                     &prg_node,
                     case.*,
                     zig_lib_directory,
+                    zig_exe_path,
                     &aux_thread_pool,
                     global_cache_directory,
                     host,
@@ -1298,6 +1300,7 @@ pub const TestContext = struct {
         root_node: *std.Progress.Node,
         case: Case,
         zig_lib_directory: Compilation.Directory,
+        zig_exe_path: []const u8,
         thread_pool: *ThreadPool,
         global_cache_directory: Compilation.Directory,
         host: std.zig.system.NativeTargetInfo,
@@ -1351,7 +1354,7 @@ pub const TestContext = struct {
             try tmp.dir.writeFile(tmp_src_path, update.src);
 
             var zig_args = std.ArrayList([]const u8).init(arena);
-            try zig_args.append(std.testing.zig_exe_path);
+            try zig_args.append(zig_exe_path);
 
             if (case.is_test) {
                 try zig_args.append("test");
@@ -1545,7 +1548,7 @@ pub const TestContext = struct {
             .link_libc = case.link_libc,
             .use_llvm = use_llvm,
             .use_stage1 = null, // We already handled stage1 tests
-            .self_exe_path = std.testing.zig_exe_path,
+            .self_exe_path = zig_exe_path,
             // TODO instead of turning off color, pass in a std.Progress.Node
             .color = .off,
             // TODO: force self-hosted linkers with stage2 backend to avoid LLD creeping in
@@ -1795,7 +1798,7 @@ pub const TestContext = struct {
                                 continue :update; // Pass test.
                             }
                             try argv.appendSlice(&[_][]const u8{
-                                std.testing.zig_exe_path,
+                                zig_exe_path,
                                 "run",
                                 "-cflags",
                                 "-std=c99",