Auto merge of #127321 - Kobzol:bootstrap-cmd-refactor-4, r=onur-ozkan

Bootstrap command refactoring: quality-of-life improvements (step 4)

Continuation of #127120.

This PR simply introduce two new functions (`BootstrapCommand:run` and `command`) that make it a bit easier to use commands in bootstrap. It also adds several `#[must_use]` annotations. This shouldn't (hopefully) have any effect on behavior.

Especially the first commit IMO makes any code that runs commands more readable, and allows using the API in a fluent way, without needing to jump back and forth between the command and the `Build(er)`.

Tracking issue: #126819

r? `@onur-ozkan`

src/bootstrap/src/core/build_steps/clean.rs

@@ -85,7 +85,7 @@ macro_rules! clean_crate_tree {
 
                 // NOTE: doesn't use `run_cargo` because we don't want to save a stamp file,
                 // and doesn't use `stream_cargo` to avoid passing `--message-format` which `clean` doesn't accept.
-                builder.run(cargo);
+                cargo.run(builder);
             }
         }
     )+ }

src/bootstrap/src/core/build_steps/compile.rs

@@ -27,7 +27,7 @@ use crate::core::builder::crate_description;
 use crate::core::builder::Cargo;
 use crate::core::builder::{Builder, Kind, PathSet, RunConfig, ShouldRun, Step, TaskPath};
 use crate::core::config::{DebuginfoLevel, LlvmLibunwind, RustcLto, TargetSelection};
-use crate::utils::exec::BootstrapCommand;
+use crate::utils::exec::command;
 use crate::utils::helpers::{
     exe, get_clang_cl_resource_dir, is_debug_info, is_dylib, symlink_dir, t, up_to_date,
 };
@@ -773,20 +773,19 @@ impl Step for StartupObjects {
             let src_file = &src_dir.join(file.to_string() + ".rs");
             let dst_file = &dst_dir.join(file.to_string() + ".o");
             if !up_to_date(src_file, dst_file) {
-                let mut cmd = BootstrapCommand::new(&builder.initial_rustc);
+                let mut cmd = command(&builder.initial_rustc);
                 cmd.env("RUSTC_BOOTSTRAP", "1");
                 if !builder.local_rebuild {
                     // a local_rebuild compiler already has stage1 features
                     cmd.arg("--cfg").arg("bootstrap");
                 }
-                builder.run(
-                    cmd.arg("--target")
-                        .arg(target.rustc_target_arg())
-                        .arg("--emit=obj")
-                        .arg("-o")
-                        .arg(dst_file)
-                        .arg(src_file),
-                );
+                cmd.arg("--target")
+                    .arg(target.rustc_target_arg())
+                    .arg("--emit=obj")
+                    .arg("-o")
+                    .arg(dst_file)
+                    .arg(src_file)
+                    .run(builder);
             }
 
             let target = sysroot_dir.join((*file).to_string() + ".o");
@@ -1488,10 +1487,10 @@ pub fn compiler_file(
     if builder.config.dry_run() {
         return PathBuf::new();
     }
-    let mut cmd = BootstrapCommand::new(compiler);
+    let mut cmd = command(compiler);
     cmd.args(builder.cflags(target, GitRepo::Rustc, c));
     cmd.arg(format!("-print-file-name={file}"));
-    let out = builder.run(cmd.capture_stdout()).stdout();
+    let out = cmd.capture_stdout().run(builder).stdout();
     PathBuf::from(out.trim())
 }
 
@@ -1836,9 +1835,8 @@ impl Step for Assemble {
             let llvm::LlvmResult { llvm_config, .. } =
                 builder.ensure(llvm::Llvm { target: target_compiler.host });
             if !builder.config.dry_run() && builder.config.llvm_tools_enabled {
-                let llvm_bin_dir = builder
-                    .run(BootstrapCommand::new(llvm_config).capture_stdout().arg("--bindir"))
-                    .stdout();
+                let llvm_bin_dir =
+                    command(llvm_config).capture_stdout().arg("--bindir").run(builder).stdout();
                 let llvm_bin_dir = Path::new(llvm_bin_dir.trim());
 
                 // Since we've already built the LLVM tools, install them to the sysroot.
@@ -2163,7 +2161,7 @@ pub fn strip_debug(builder: &Builder<'_>, target: TargetSelection, path: &Path)
     }
 
     let previous_mtime = FileTime::from_last_modification_time(&path.metadata().unwrap());
-    builder.run(BootstrapCommand::new("strip").capture().arg("--strip-debug").arg(path));
+    command("strip").capture().arg("--strip-debug").arg(path).run(builder);
 
     // After running `strip`, we have to set the file modification time to what it was before,
     // otherwise we risk Cargo invalidating its fingerprint and rebuilding the world next time