normalize path to relative

Cargo.lock

@@ -974,6 +974,7 @@ dependencies = [
  "notify-debouncer-mini",
  "once_cell",
  "opener",
+ "pathdiff",
  "predicates",
  "pretty_assertions",
  "pulldown-cmark",
@@ -1151,6 +1152,12 @@ dependencies = [
  "windows-targets 0.48.1",
 ]
 
+[[package]]
+name = "pathdiff"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8835116a5c179084a830efb3adc117ab007512b535bc1a21c991d3b32a6b44dd"
+
 [[package]]
 name = "percent-encoding"
 version = "2.3.0"

Cargo.toml

@@ -28,6 +28,7 @@ log = "0.4.17"
 memchr = "2.5.0"
 opener = "0.6.1"
 pulldown-cmark = { version = "0.9.3", default-features = false }
+pathdiff = "0.2.1"
 regex = "1.8.1"
 serde = { version = "1.0.163", features = ["derive"] }
 serde_json = "1.0.96"

src/cmd/watch.rs

@@ -4,6 +4,7 @@ use ignore::gitignore::Gitignore;
 use mdbook::errors::Result;
 use mdbook::utils;
 use mdbook::MDBook;
+use pathdiff::diff_paths;
 use std::env;
 use std::path::{Path, PathBuf};
 use std::sync::mpsc::channel;
@@ -93,11 +94,10 @@ fn filter_ignored_files(ignore: Gitignore, paths: &[PathBuf]) -> Vec<PathBuf> {
     paths
         .iter()
         .filter(|path| {
-            let normalized_path = path
-                .strip_prefix(&current_dir)
-                .expect("Could not normalize path");
+            let relative_path =
+                diff_paths(&current_dir, &path).expect("One of the paths should be an absolute");
             !ignore
-                .matched_path_or_any_parents(normalized_path, normalized_path.is_dir())
+                .matched_path_or_any_parents(&relative_path, relative_path.is_dir())
                 .is_ignore()
         })
         .map(|path| path.to_path_buf())