feat: starting to work on memchr

dotme-path/Cargo.toml

@@ -9,3 +9,4 @@ documentation.workspace = true
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+memchr = "2.7.1"

dotme-path/src/interpolate_env/mod.rs

@@ -3,6 +3,7 @@ mod error;
 #[cfg(test)]
 mod tests;
 
+use memchr;
 use std::{
     ffi::OsStr,
     path::{Path, PathBuf},
@@ -27,5 +28,15 @@ pub fn interpoate_env(path: &Path) -> Result<PathBuf, Error> {
 
 fn interpolate_part(part: &OsStr) -> Result<&[u8], Error> {
     let bytes = part.as_encoded_bytes();
+    let range = 0..bytes.len();
+    let mut sliding_pointer = range.start;
+    while sliding_pointer < range.end {
+        let env_start_pos = match memchr::memchr(b'$', &bytes[sliding_pointer..]) {
+            Some(start_pos) => sliding_pointer + start_pos,
+            None => break,
+        };
+        println!("env variable starting at position {}", env_start_pos);
+        sliding_pointer += 1;
+    }
     Ok(bytes)
 }

dotme-path/src/interpolate_env/tests.rs

@@ -2,8 +2,8 @@ use super::*;
 
 #[test]
 fn it_should_parse_basic_env() {
-    let input = Path::new("$CARGO_PKG_NAME");
+    let input = Path::new("someting/test/$CARGO_PKG_NAME");
     let result = interpoate_env(input).expect("Should parse env variable");
-    let expected = PathBuf::from("dotme-path");
+    let expected = PathBuf::from("something/test/dotme-path");
     assert_eq!(expected, result);
 }