From af7afbd08b9c74c0d65ddda9f495e497c4c5e5a1 Mon Sep 17 00:00:00 2001
From: Andrew Kelley <andrew@ziglang.org>
Date: Sun, 16 Jun 2024 19:29:05 -0700
Subject: [PATCH] std.Build.Step: split evalChildProcess into two functions

Now there is `captureChildProcess` which gives access to the
`std.process.Child.RunResult`, which is useful for accessing the stdout.

It also accepts and passes an optional `std.Progress.Node` to the child.
---
 lib/std/Build/Step.zig | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/std/Build/Step.zig b/lib/std/Build/Step.zig
index b6aed17076..c9902220fd 100644
--- a/lib/std/Build/Step.zig
+++ b/lib/std/Build/Step.zig
@@ -269,7 +269,17 @@ const Allocator = std.mem.Allocator;
 const assert = std.debug.assert;
 const builtin = @import("builtin");
 
-pub fn evalChildProcess(s: *Step, argv: []const []const u8) !void {
+pub fn evalChildProcess(s: *Step, argv: []const []const u8) ![]u8 {
+    const run_result = try captureChildProcess(s, std.Progress.Node.none, argv);
+    try handleChildProcessTerm(s, run_result.term, null, argv);
+    return run_result.stdout;
+}
+
+pub fn captureChildProcess(
+    s: *Step,
+    progress_node: std.Progress.Node,
+    argv: []const []const u8,
+) !std.process.Child.RunResult {
     const arena = s.owner.allocator;
 
     try handleChildProcUnsupported(s, null, argv);
@@ -278,13 +288,14 @@ pub fn evalChildProcess(s: *Step, argv: []const []const u8) !void {
     const result = std.process.Child.run(.{
         .allocator = arena,
         .argv = argv,
+        .progress_node = progress_node,
     }) catch |err| return s.fail("unable to spawn {s}: {s}", .{ argv[0], @errorName(err) });
 
     if (result.stderr.len > 0) {
         try s.result_error_msgs.append(arena, result.stderr);
     }
 
-    try handleChildProcessTerm(s, result.term, null, argv);
+    return result;
 }
 
 pub fn fail(step: *Step, comptime fmt: []const u8, args: anytype) error{ OutOfMemory, MakeFailed } {