unify git command preperation

Due to #125954, we had to modify git invocations with
certain flags in #126255. However, because there are so many
instances of `Command::new("git")` in bootstrap, it is difficult to apply these solutions to all of
them.

This PR creates a helper function that unifies the git usage in bootstrap. Meaning, whenever special flags
or hacks are needed, we can apply them to this single function which makes things much simpler for the bootstrap team.

Signed-off-by: onur-ozkan <[email protected]>

src/bootstrap/src/core/build_steps/format.rs

@@ -1,7 +1,7 @@
 //! Runs rustfmt on the repository.
 
 use crate::core::builder::Builder;
-use crate::utils::helpers::{output, program_out_of_date, t};
+use crate::utils::helpers::{self, output, program_out_of_date, t};
 use build_helper::ci::CiEnv;
 use build_helper::git::get_git_modified_files;
 use ignore::WalkBuilder;
@@ -160,7 +160,7 @@ pub fn format(build: &Builder<'_>, check: bool, all: bool, paths: &[PathBuf]) {
             override_builder.add(&format!("!{ignore}")).expect(&ignore);
         }
     }
-    let git_available = match Command::new("git")
+    let git_available = match helpers::git(None)
         .arg("--version")
         .stdout(Stdio::null())
         .stderr(Stdio::null())
@@ -172,9 +172,7 @@ pub fn format(build: &Builder<'_>, check: bool, all: bool, paths: &[PathBuf]) {
 
     let mut adjective = None;
     if git_available {
-        let in_working_tree = match build
-            .config
-            .git()
+        let in_working_tree = match helpers::git(Some(&build.src))
             .arg("rev-parse")
             .arg("--is-inside-work-tree")
             .stdout(Stdio::null())
@@ -186,9 +184,7 @@ pub fn format(build: &Builder<'_>, check: bool, all: bool, paths: &[PathBuf]) {
         };
         if in_working_tree {
             let untracked_paths_output = output(
-                build
-                    .config
-                    .git()
+                helpers::git(Some(&build.src))
                     .arg("status")
                     .arg("--porcelain")
                     .arg("-z")

src/bootstrap/src/core/build_steps/llvm.rs

@@ -159,7 +159,7 @@ pub(crate) fn detect_llvm_sha(config: &Config, is_git: bool) -> String {
         // in that case.
         let closest_upstream = get_git_merge_base(&config.git_config(), Some(&config.src))
             .unwrap_or_else(|_| "HEAD".into());
-        let mut rev_list = config.git();
+        let mut rev_list = helpers::git(Some(&config.src));
         rev_list.args(&[
             PathBuf::from("rev-list"),
             format!("--author={}", config.stage0_metadata.config.git_merge_commit_email).into(),
@@ -252,7 +252,7 @@ pub(crate) fn is_ci_llvm_modified(config: &Config) -> bool {
         // We assume we have access to git, so it's okay to unconditionally pass
         // `true` here.
         let llvm_sha = detect_llvm_sha(config, true);
-        let head_sha = output(config.git().arg("rev-parse").arg("HEAD"));
+        let head_sha = output(helpers::git(Some(&config.src)).arg("rev-parse").arg("HEAD"));
         let head_sha = head_sha.trim();
         llvm_sha == head_sha
     }

src/bootstrap/src/core/build_steps/setup.rs

@@ -8,7 +8,7 @@
 use crate::core::builder::{Builder, RunConfig, ShouldRun, Step};
 use crate::t;
 use crate::utils::change_tracker::CONFIG_CHANGE_HISTORY;
-use crate::utils::helpers::hex_encode;
+use crate::utils::helpers::{self, hex_encode};
 use crate::Config;
 use sha2::Digest;
 use std::env::consts::EXE_SUFFIX;
@@ -482,10 +482,13 @@ impl Step for Hook {
 
 // install a git hook to automatically run tidy, if they want
 fn install_git_hook_maybe(config: &Config) -> io::Result<()> {
-    let git = config.git().args(["rev-parse", "--git-common-dir"]).output().map(|output| {
-        assert!(output.status.success(), "failed to run `git`");
-        PathBuf::from(t!(String::from_utf8(output.stdout)).trim())
-    })?;
+    let git = helpers::git(Some(&config.src))
+        .args(["rev-parse", "--git-common-dir"])
+        .output()
+        .map(|output| {
+            assert!(output.status.success(), "failed to run `git`");
+            PathBuf::from(t!(String::from_utf8(output.stdout)).trim())
+        })?;
     let hooks_dir = git.join("hooks");
     let dst = hooks_dir.join("pre-push");
     if dst.exists() {

src/bootstrap/src/core/build_steps/toolstate.rs

@@ -5,15 +5,14 @@
 //! [Toolstate]: https://forge.rust-lang.org/infra/toolstate.html
 
 use crate::core::builder::{Builder, RunConfig, ShouldRun, Step};
-use crate::utils::helpers::t;
+use crate::utils::helpers::{self, t};
 use serde_derive::{Deserialize, Serialize};
 use std::collections::HashMap;
 use std::env;
 use std::fmt;
 use std::fs;
 use std::io::{Seek, SeekFrom};
 use std::path::{Path, PathBuf};
-use std::process::Command;
 use std::time;
 
 // Each cycle is 42 days long (6 weeks); the last week is 35..=42 then.
@@ -102,12 +101,8 @@ fn print_error(tool: &str, submodule: &str) {
 
 fn check_changed_files(toolstates: &HashMap<Box<str>, ToolState>) {
     // Changed files
-    let output = std::process::Command::new("git")
-        .arg("diff")
-        .arg("--name-status")
-        .arg("HEAD")
-        .arg("HEAD^")
-        .output();
+    let output =
+        helpers::git(None).arg("diff").arg("--name-status").arg("HEAD").arg("HEAD^").output();
     let output = match output {
         Ok(o) => o,
         Err(e) => {
@@ -324,7 +319,7 @@ fn checkout_toolstate_repo() {
         t!(fs::remove_dir_all(TOOLSTATE_DIR));
     }
 
-    let status = Command::new("git")
+    let status = helpers::git(None)
         .arg("clone")
         .arg("--depth=1")
         .arg(toolstate_repo())
@@ -342,7 +337,7 @@ fn checkout_toolstate_repo() {
 /// Sets up config and authentication for modifying the toolstate repo.
 fn prepare_toolstate_config(token: &str) {
     fn git_config(key: &str, value: &str) {
-        let status = Command::new("git").arg("config").arg("--global").arg(key).arg(value).status();
+        let status = helpers::git(None).arg("config").arg("--global").arg(key).arg(value).status();
         let success = match status {
             Ok(s) => s.success(),
             Err(_) => false,
@@ -406,8 +401,7 @@ fn commit_toolstate_change(current_toolstate: &ToolstateData) {
         publish_test_results(current_toolstate);
 
         // `git commit` failing means nothing to commit.
-        let status = t!(Command::new("git")
-            .current_dir(TOOLSTATE_DIR)
+        let status = t!(helpers::git(Some(Path::new(TOOLSTATE_DIR)))
             .arg("commit")
             .arg("-a")
             .arg("-m")
@@ -418,8 +412,7 @@ fn commit_toolstate_change(current_toolstate: &ToolstateData) {
             break;
         }
 
-        let status = t!(Command::new("git")
-            .current_dir(TOOLSTATE_DIR)
+        let status = t!(helpers::git(Some(Path::new(TOOLSTATE_DIR)))
             .arg("push")
             .arg("origin")
             .arg("master")
@@ -431,15 +424,13 @@ fn commit_toolstate_change(current_toolstate: &ToolstateData) {
         }
         eprintln!("Sleeping for 3 seconds before retrying push");
         std::thread::sleep(std::time::Duration::from_secs(3));
-        let status = t!(Command::new("git")
-            .current_dir(TOOLSTATE_DIR)
+        let status = t!(helpers::git(Some(Path::new(TOOLSTATE_DIR)))
             .arg("fetch")
             .arg("origin")
             .arg("master")
             .status());
         assert!(status.success());
-        let status = t!(Command::new("git")
-            .current_dir(TOOLSTATE_DIR)
+        let status = t!(helpers::git(Some(Path::new(TOOLSTATE_DIR)))
             .arg("reset")
             .arg("--hard")
             .arg("origin/master")
@@ -458,7 +449,7 @@ fn commit_toolstate_change(current_toolstate: &ToolstateData) {
 /// `publish_toolstate.py` script if the PR passes all tests and is merged to
 /// master.
 fn publish_test_results(current_toolstate: &ToolstateData) {
-    let commit = t!(std::process::Command::new("git").arg("rev-parse").arg("HEAD").output());
+    let commit = t!(helpers::git(None).arg("rev-parse").arg("HEAD").output());
     let commit = t!(String::from_utf8(commit.stdout));
 
     let toolstate_serialized = t!(serde_json::to_string(&current_toolstate));

src/bootstrap/src/core/config/config.rs

@@ -20,7 +20,7 @@ use crate::core::build_steps::llvm;
 use crate::core::config::flags::{Color, Flags, Warnings};
 use crate::utils::cache::{Interned, INTERNER};
 use crate::utils::channel::{self, GitInfo};
-use crate::utils::helpers::{exe, output, t};
+use crate::utils::helpers::{self, exe, output, t};
 use build_helper::exit;
 use serde::{Deserialize, Deserializer};
 use serde_derive::Deserialize;
@@ -1248,7 +1248,7 @@ impl Config {
 
         // Infer the source directory. This is non-trivial because we want to support a downloaded bootstrap binary,
         // running on a completely different machine from where it was compiled.
-        let mut cmd = Command::new("git");
+        let mut cmd = helpers::git(None);
         // NOTE: we cannot support running from outside the repository because the only other path we have available
         // is set at compile time, which can be wrong if bootstrap was downloaded rather than compiled locally.
         // We still support running outside the repository if we find we aren't in a git directory.
@@ -2090,15 +2090,6 @@ impl Config {
         build_helper::util::try_run(cmd, self.is_verbose())
     }
 
-    /// A git invocation which runs inside the source directory.
-    ///
-    /// Use this rather than `Command::new("git")` in order to support out-of-tree builds.
-    pub(crate) fn git(&self) -> Command {
-        let mut git = Command::new("git");
-        git.current_dir(&self.src);
-        git
-    }
-
     pub(crate) fn test_args(&self) -> Vec<&str> {
         let mut test_args = match self.cmd {
             Subcommand::Test { ref test_args, .. }
@@ -2130,7 +2121,7 @@ impl Config {
             "`Config::read_file_by_commit` is not supported in non-git sources."
         );
 
-        let mut git = self.git();
+        let mut git = helpers::git(Some(&self.src));
         git.arg("show").arg(format!("{commit}:{}", file.to_str().unwrap()));
         output(&mut git)
     }
@@ -2436,15 +2427,16 @@ impl Config {
         };
 
         // Handle running from a directory other than the top level
-        let top_level = output(self.git().args(["rev-parse", "--show-toplevel"]));
+        let top_level =
+            output(helpers::git(Some(&self.src)).args(["rev-parse", "--show-toplevel"]));
         let top_level = top_level.trim_end();
         let compiler = format!("{top_level}/compiler/");
         let library = format!("{top_level}/library/");
 
         // Look for a version to compare to based on the current commit.
         // Only commits merged by bors will have CI artifacts.
         let merge_base = output(
-            self.git()
+            helpers::git(Some(&self.src))
                 .arg("rev-list")
                 .arg(format!("--author={}", self.stage0_metadata.config.git_merge_commit_email))
                 .args(["-n1", "--first-parent", "HEAD"]),
@@ -2459,8 +2451,7 @@ impl Config {
         }
 
         // Warn if there were changes to the compiler or standard library since the ancestor commit.
-        let has_changes = !t!(self
-            .git()
+        let has_changes = !t!(helpers::git(Some(&self.src))
             .args(["diff-index", "--quiet", commit, "--", &compiler, &library])
             .status())
         .success();
@@ -2533,13 +2524,14 @@ impl Config {
         if_unchanged: bool,
     ) -> Option<String> {
         // Handle running from a directory other than the top level
-        let top_level = output(self.git().args(["rev-parse", "--show-toplevel"]));
+        let top_level =
+            output(helpers::git(Some(&self.src)).args(["rev-parse", "--show-toplevel"]));
         let top_level = top_level.trim_end();
 
         // Look for a version to compare to based on the current commit.
         // Only commits merged by bors will have CI artifacts.
         let merge_base = output(
-            self.git()
+            helpers::git(Some(&self.src))
                 .arg("rev-list")
                 .arg(format!("--author={}", self.stage0_metadata.config.git_merge_commit_email))
                 .args(["-n1", "--first-parent", "HEAD"]),
@@ -2554,7 +2546,7 @@ impl Config {
         }
 
         // Warn if there were changes to the compiler or standard library since the ancestor commit.
-        let mut git = self.git();
+        let mut git = helpers::git(Some(&self.src));
         git.args(["diff-index", "--quiet", commit, "--"]);
 
         for path in modified_paths {