From df544cace97b57b318dba439d4e67a3953388477 Mon Sep 17 00:00:00 2001
From: iddev5 <ayushbardhan5@gmail.com>
Date: Fri, 18 Mar 2022 13:10:41 +0530
Subject: [PATCH 1/3] std: explicitly handle error.UnexpectedExitCode in
 build_runner

RunStep on unexpected exit code used to return error.UncleanExit, which
was confusing and unclear. When it was changed, the error handling code
in build_runner was not modified, which produced an error trace.

This commit explicitly handles error.UnexpectedExitCode in build_runner
so that the behavior now matches that of zig 0.8.1 after which it was
regressed.
---
 lib/std/special/build_runner.zig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/std/special/build_runner.zig b/lib/std/special/build_runner.zig
index eb83ef8fcd..bdc2d0457e 100644
--- a/lib/std/special/build_runner.zig
+++ b/lib/std/special/build_runner.zig
@@ -205,7 +205,7 @@ pub fn main() !void {
             error.InvalidStepName => {
                 return usageAndErr(builder, true, stderr_stream);
             },
-            error.UncleanExit => process.exit(1),
+            error.UnexpectedExitCode, error.UncleanExit => process.exit(1),
             else => return err,
         }
     };

From 8d3e7aa5e0a7b3956a5ba8cf2c85d756ab581465 Mon Sep 17 00:00:00 2001
From: iddev5 <ayushbardhan5@gmail.com>
Date: Mon, 4 Apr 2022 18:33:47 +0530
Subject: [PATCH 2/3] std.testing: add function zigBuild for running zig build
 runner commands

---
 lib/std/testing.zig | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/lib/std/testing.zig b/lib/std/testing.zig
index 4146e033b4..c979a555b8 100644
--- a/lib/std/testing.zig
+++ b/lib/std/testing.zig
@@ -450,6 +450,36 @@ pub fn buildExe(zigexec: []const u8, zigfile: []const u8, binfile: []const u8) !
     try expectEqual(ret_val, .{ .Exited = 0 });
 }
 
+/// Spawns a zig build runner process 'zigexec build subcmd' and
+/// expects success
+/// If specified, runs zig build in the cwd path
+/// If specified, uses the specified lib_dir for zig standard library
+/// instead of compiler's default library directory
+pub fn runZigBuild(zigexec: []const u8, options: struct {
+    subcmd: ?[]const u8 = null,
+    cwd: ?[]const u8 = null,
+    lib_dir: ?[]const u8 = null,
+}) !std.ChildProcess.ExecResult {
+    var args = std.ArrayList([]const u8).init(allocator);
+    defer args.deinit();
+
+    try args.appendSlice(&.{ zigexec, "build" });
+    if (options.subcmd) |subcmd| try args.append(subcmd);
+    if (options.lib_dir) |lib_dir| try args.append(lib_dir);
+
+    var result = try std.ChildProcess.exec(.{
+        .allocator = allocator,
+        .argv = args.items,
+        .cwd = if (options.cwd) |c| c else null,
+    });
+    errdefer {
+        allocator.free(result.stdout);
+        allocator.free(result.stderr);
+    }
+
+    return result;
+}
+
 test "expectEqual nested array" {
     const a = [2][2]f32{
         [_]f32{ 1.0, 0.0 },

From d9f9948b6536339747322b8a04431116b698892e Mon Sep 17 00:00:00 2001
From: iddev5 <ayushbardhan5@gmail.com>
Date: Mon, 4 Apr 2022 18:34:19 +0530
Subject: [PATCH 3/3] std.build: add test for issue 10381

---
 lib/std/build.zig | 55 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/lib/std/build.zig b/lib/std/build.zig
index f1287c7be5..902849a379 100644
--- a/lib/std/build.zig
+++ b/lib/std/build.zig
@@ -3492,3 +3492,58 @@ test "LibExeObjStep.addPackage" {
     const dupe = exe.packages.items[0];
     try std.testing.expectEqualStrings(pkg_top.name, dupe.name);
 }
+
+test "build_runner issue 10381" {
+    if (builtin.os.tag == .wasi) return error.SkipZigTest;
+
+    const progstr =
+        \\ pub fn main() u8 {
+        \\     return 1;
+        \\ }
+    ;
+
+    const buildstr =
+        \\ const std = @import("std");
+        \\ pub fn build(b: *std.build.Builder) void {
+        \\     const exe = b.addExecutable("source", "source.zig");
+        \\     exe.install();
+        \\     const run_cmd = exe.run();
+        \\     run_cmd.step.dependOn(b.getInstallStep());
+        \\     const run_step = b.step("run", "Run");
+        \\     run_step.dependOn(&run_cmd.step);
+        \\ }
+    ;
+
+    const testing = std.testing;
+    const allocator = testing.allocator;
+
+    var it = try std.process.argsWithAllocator(allocator);
+    defer it.deinit();
+    const testargs = try testing.getTestArgs(&it);
+
+    var tmpdir = testing.tmpDir(.{ .no_follow = true });
+    defer tmpdir.cleanup();
+    const tmpdir_path = try tmpdir.getFullPath(allocator);
+    defer allocator.free(tmpdir_path);
+
+    try tmpdir.dir.writeFile("source.zig", progstr);
+    try tmpdir.dir.writeFile("build.zig", buildstr);
+
+    const cwd_path = try std.process.getCwdAlloc(allocator);
+    defer allocator.free(cwd_path);
+    const lib_dir = try std.fs.path.join(allocator, &.{ cwd_path, "lib" });
+    defer allocator.free(lib_dir);
+
+    const result = try testing.runZigBuild(testargs.zigexec, .{
+        .subcmd = "run",
+        .cwd = tmpdir_path,
+        .lib_dir = lib_dir,
+    });
+    defer {
+        allocator.free(result.stdout);
+        allocator.free(result.stderr);
+    }
+
+    try testing.expectEqual(result.term, .{ .Exited = 1 });
+    try testing.expect(std.mem.indexOf(u8, result.stderr, "error: UnexpectedExitCode") == null);
+}