Added signs replacement (homedir and previous command) and reformatted

src/main.rs

@@ -121,22 +121,34 @@ fn print_history() -> Result<(), std::io::Error> {
 fn get_hist_from_number(number: &i32) -> Option<String> {
     //Returns a command from its number in hist file
     let filepath = dirs::home_dir().unwrap().join("history.rshell");
-    if filepath.exists() {
-        let file = File::open(filepath).expect("Error opening history file, should NOT happen");
-        let mut reader = BufReader::new(file).lines();
-        for line in reader {
-            let current_line = line.expect("Empty history file ? Please rm it");
-            let mut s = current_line.split_whitespace();
-            let n: i32 = s.next().expect("Error reading a line in hist file").parse().unwrap();
-            let c = s.next().expect("No command!");
-            if &n == number {
-                return Some(String::from(c));
-            }
-        }
-        return None;
-    } else {
+
+    if filepath.exists() == false {
         return None;
     }
+
+    let file = File::open(filepath)
+        .expect("Error opening history file...");
+
+    if file.metadata().unwrap().len() < 1 {
+        return None;
+    }
+
+    let mut reader = BufReader::new(file).lines();
+
+    for line in reader {
+        let current_line = line
+            .expect("Empty history file ? Please rm it");
+        let mut s = current_line.split_whitespace();
+        let n: i32 = s.next()
+            .expect("Error reading a line in hist file")
+            .parse()
+            .unwrap();
+        let c = s.next().expect("No command!");
+        if &n == number {
+            return Some(String::from(c));
+        }
+    }
+    return None;
 }
 
 fn treat_history_callback(line: &str) -> Option<String> {
@@ -181,30 +193,48 @@ fn build_prompt() -> String {
     return prompt;
 }
 
+fn replace_signs(line: String) -> String {
+    let mut ayo = String::from(&line);
+    if ayo.contains('~') {
+        let homedir = dirs::home_dir().unwrap().into_os_string().into_string().unwrap();
+        let result = str::replace(&ayo, "~", &homedir);
+        ayo = String::from(result);
+    }
+    
+    if ayo.contains("!!") {
+        let prev_comm = get_hist_from_number(&get_history_number().unwrap()).unwrap();
+        let result = str::replace(&ayo, "!!", &prev_comm);
+        ayo = String::from(result);
+    }
+
+    return ayo;
+}
 
 fn main(){
     loop {
         print!("{}", build_prompt());
         stdout().flush();
-
         let mut input = String::new();
         let bytes = stdin().read_line(&mut input).unwrap();
-        if (bytes > 0) && (input != String::from("\n"))  {
-            if input.starts_with("!") {
-                let command_found = treat_history_callback(&input);
-                match command_found {
-                    Some(c) => {
-                        write_to_history(&c);
-                        process_line(c);
+        input = replace_signs(input);
+
+        //history callback
+        if (bytes > 0) && (input != String::from("\n")) && (input.starts_with('!'))  {
+            let command_found = treat_history_callback(&input);
+            match command_found {
+                Some(c) => {
+                    write_to_history(&c);
+                    process_line(c);
                     },
-                    None => ()
-                };
-            } else {
-                write_to_history(&input);
-                if process_line(input) {
-                    return
-                }
+                None => ()
+            };
+        //Regular command
+        } else if (bytes > 0) && (input != String::from("\n")) {
+            write_to_history(&input);
+            if process_line(input) {
+                return
             }
+        //Nothing
         } else {
             //Command was empty, new line
             continue;
@@ -220,16 +250,17 @@ mod tests {
 
     fn inittests() {
         let filepath = dirs::home_dir().unwrap().join("history.rshell");
-        //if the file exists, new will truncate it
+
         let file = File::create(&filepath).expect("Could not create test history");
         writeln!(&file, "1 ls");
+        writeln!(&file, "2 pwd");
     }
 
     #[test]
     fn test_gethistnumber() {
         inittests();
         let mynumber = get_history_number().unwrap();
-        assert_eq!(mynumber, 1);
+        assert_eq!(mynumber, 2);
     }
 
     #[test]
@@ -239,6 +270,20 @@ mod tests {
         assert_eq!(mycmd, String::from("ls"));
     }
 
+    #[test]
+    fn test_history_callback() {
+        inittests();
+        let expected = String::from("ls");
+        assert_eq!(treat_history_callback("!1"), Some(expected));
+    }
+
+    #[test]
+    fn test_replace_signs() {
+        inittests();
+        let homedir = dirs::home_dir().unwrap().into_os_string().into_string().unwrap();
+        assert_eq!(replace_signs(String::from("ls ~ && echo !!")), String::from(format!("ls {} && echo pwd", homedir)));
+    }
+
     #[test]
     fn test_writehistline() {
         inittests();
@@ -250,18 +295,11 @@ mod tests {
         let file = File::open(filepath).expect("Error");
         let mut reader = BufReader::new(file).lines();
         let myline = String::from(reader.last().unwrap().expect("Error"));
-        let expected = String::from("2 pwd");
+        let expected = String::from("3 pwd");
 
         assert_eq!(myline.trim(), expected.trim()); 
     }
 
-    #[test]
-    fn test_history_callback() {
-        inittests();
-        let expected = String::from("ls");
-        assert_eq!(treat_history_callback("!1"), Some(expected));
-    }
-
 
 }