Merge commit '98ed962c7d3eebe12c97588e61245273d265e72f' into master

compiler/rustc_codegen_gcc/build_system/src/fmt.rs

@@ -0,0 +1,35 @@
+use crate::utils::run_command_with_output;
+use std::ffi::OsStr;
+use std::path::Path;
+
+fn show_usage() {
+    println!(
+        r#"
+`fmt` command help:
+
+    --check                : Pass `--check` argument to `cargo fmt` commands
+    --help                 : Show this help"#
+    );
+}
+
+pub fn run() -> Result<(), String> {
+    let mut check = false;
+    // We skip binary name and the `info` command.
+    let mut args = std::env::args().skip(2);
+    while let Some(arg) = args.next() {
+        match arg.as_str() {
+            "--help" => {
+                show_usage();
+                return Ok(());
+            }
+            "--check" => check = true,
+            _ => return Err(format!("Unknown option {}", arg)),
+        }
+    }
+
+    let cmd: &[&dyn AsRef<OsStr>] =
+        if check { &[&"cargo", &"fmt", &"--check"] } else { &[&"cargo", &"fmt"] };
+
+    run_command_with_output(cmd, Some(&Path::new(".")))?;
+    run_command_with_output(cmd, Some(&Path::new("build_system")))
+}