process(), finished part 1

src/main.rs

@@ -5,7 +5,6 @@ fn read_lines(filename: &str) -> Vec<String> {
 
     for line in read_to_string(filename).unwrap().lines() {
         result.push(line.to_string())
-        // result.push(line);
     }
 
     result
@@ -34,13 +33,24 @@ fn parse_line(line: &str) -> i32 {
     j
 }
 
+fn process(lines: Vec<String>) -> i32 {
+    let sum: i32 = lines.iter().fold(0, |acc, line| {
+        let line_str: &str = line.as_str();
+        let val = parse_line(line_str);
+        acc + val
+    });
+    sum
+}
+
 fn main() {
-    println!("Hello, world!");
+    let lines: Vec<String> = read_lines("input.txt");
+    let sum = process(lines);
+    println!("{}", sum);
 }
 
 #[cfg(test)]
 mod tests {
-    use crate::parse_line;
+    use crate::{parse_line, process};
 
     #[test]
     fn test_parse_line_1() {
@@ -89,4 +99,20 @@ mod tests {
         // assert
         assert_eq!(calib_val, 77);
     }
+
+    #[test]
+    fn test_process() {
+        // arrange
+        let mut v: Vec<String> = Vec::new();
+        v.push(String::from("1abc2"));
+        v.push(String::from("pqr3stu8vwx"));
+        v.push(String::from("a1b2c3d4e5f"));
+        v.push(String::from("treb7uchet"));
+
+        // act
+        let sum: i32 = process(v);
+
+        // assert
+        assert_eq!(sum, 142);
+    }
 }