save profile report to file

Author: Shourya742

src/bootstrap/src/utils/exec.rs

@@ -10,9 +10,12 @@
 use std::collections::HashMap;
 use std::ffi::{OsStr, OsString};
 use std::fmt::{Debug, Formatter};
+use std::fs::File;
 use std::hash::Hash;
+use std::io::{BufWriter, Write};
 use std::panic::Location;
 use std::path::Path;
+use std::process;
 use std::process::{
     Child, ChildStderr, ChildStdout, Command, CommandArgs, CommandEnvs, ExitStatus, Output, Stdio,
 };
@@ -100,10 +103,22 @@ impl CommandProfiler {
     }
 
     pub fn report_summary(&self) {
+        let pid = process::id();
+        let filename = format!("bootstrap-profile-{pid}.txt");
+
+        let file = match File::create(&filename) {
+            Ok(f) => f,
+            Err(e) => {
+                eprintln!("Failed to create profiler output file: {e}");
+                return;
+            }
+        };
+
+        let mut writer = BufWriter::new(file);
         let stats = self.stats.lock().unwrap();
 
         for (key, profile) in stats.iter() {
-            println!("\nCommand: {:?}", key.program);
+            writeln!(writer, "Command: {:?}", key.program).unwrap();
 
             let mut hits = 0;
             let mut runs = 0;
@@ -113,25 +128,37 @@ impl CommandProfiler {
                 match trace {
                     ExecutionTrace::CacheHit { timestamp } => {
                         hits += 1;
-                        println!("  - Cache hit at: {timestamp:?}");
+                        writeln!(writer, "  - Cache hit at:   {:?}", timestamp).unwrap();
                     }
                     ExecutionTrace::Executed { duration, timestamp } => {
                         runs += 1;
                         if max_duration.is_none_or(|d| *duration > d) {
                             max_duration = Some(*duration);
                         }
-                        println!("  - Executed at: {timestamp:?}, duration: {duration:.2?}");
+                        writeln!(
+                            writer,
+                            "  - Executed at:    {:?}, duration: {:.2?}",
+                            timestamp, duration
+                        )
+                        .unwrap();
                     }
                 }
             }
 
             let duration_str = match max_duration {
-                Some(d) => format!("{d:.2?}"),
+                Some(d) => format!("{:.2?}", d),
                 None => "-".into(),
             };
 
-            println!("Summary: {runs} run(s), {hits} hit(s), max_duration={duration_str}");
+            writeln!(
+                writer,
+                "Summary: {runs} run(s), {hits} hit(s), max_duration={duration_str}\n"
+            )
+            .unwrap();
         }
+
+        // Print a message to user
+        println!("Command profiler report saved to {filename}");
     }
 }