Fix bug and tests

tree/readlink.rs

@@ -210,14 +210,25 @@ fn recursive_resolve(starting_path_buf: PathBuf) -> Result<PathBuf, String> {
     loop {
         match fs::read_link(current_path_buf.as_path()) {
             Ok(pa) => {
-                if !encountered_paths.insert(pa.as_os_str().to_owned()) {
+                if pa.is_absolute() {
+                    current_path_buf = pa;
+                } else {
+                    if !current_path_buf.pop() {
+                        return Err(format!(
+                            "Could not remove last path segment from path \"{}\")",
+                            current_path_buf.to_string_lossy()
+                        ));
+                    }
+
+                    current_path_buf.push(pa);
+                }
+
+                if !encountered_paths.insert(current_path_buf.as_os_str().to_owned()) {
                     return Err(format!(
                         "Infinite symbolic link loop detected at \"{}\")",
-                        pa.to_string_lossy()
+                        current_path_buf.to_string_lossy()
                     ));
                 }
-
-                current_path_buf = pa;
             }
             Err(_) => {
                 break;

tree/tests/readlink/mod.rs

@@ -63,7 +63,10 @@ fn test_readlink_non_existent_file() {
 
     run_test(TestPlan {
         cmd: String::from("readlink"),
-        args: vec![non_existent_path.to_str().unwrap().to_string()],
+        args: vec![
+            "-v".to_owned(),
+            non_existent_path.to_str().unwrap().to_string(),
+        ],
         stdin_data: String::new(),
         expected_out: String::new(),
         expected_err: format!(
@@ -84,7 +87,7 @@ fn test_readlink_not_a_symlink() {
 
     run_test(TestPlan {
         cmd: String::from("readlink"),
-        args: vec![file_path.to_str().unwrap().to_string()],
+        args: vec!["-v".to_owned(), file_path.to_str().unwrap().to_string()],
         stdin_data: String::new(),
         expected_out: String::new(),
         expected_err: format!(