fix: treat Windows drive-letter paths as local files

src/core.rs

@@ -16,7 +16,7 @@ use crate::html::{
     has_favicon, html_to_dom, serialize_document, set_base_url, set_charset, set_robots, walk,
 };
 use crate::session::Session;
-use crate::url::{create_data_url, resolve_url};
+use crate::url::{create_data_url, is_windows_drive_path, resolve_url};
 
 #[derive(Debug)]
 pub struct MonolithError {
@@ -167,7 +167,7 @@ pub fn create_monolithic_document_from_data(
     } else {
         // Custom base URL provided
         match Url::parse(&custom_base_url) {
-            Ok(parsed_url) => {
+            Ok(parsed_url) if !is_windows_drive_path(&custom_base_url) => {
                 if parsed_url.scheme() == "file" {
                     // File base URLs can only work with documents saved from filesystem
                     if base_url.scheme() == "file" {
@@ -177,7 +177,7 @@ pub fn create_monolithic_document_from_data(
                     base_url = parsed_url;
                 }
             }
-            Err(_) => {
+            _ => {
                 // Failed to parse given base URL, perhaps it's a filesystem path?
                 if base_url.scheme() == "file" {
                     // Relative paths could work for documents saved from filesystem
@@ -358,7 +358,7 @@ pub fn create_monolithic_document(
 
     let mut target_url = match target.as_str() {
         target_str => match Url::parse(target_str) {
-            Ok(target_url) => match target_url.scheme() {
+            Ok(target_url) if !is_windows_drive_path(target_str) => match target_url.scheme() {
                 "data" | "file" | "http" | "https" => target_url,
                 unsupported_scheme => {
                     return Err(MonolithError::new(&format!(
@@ -367,7 +367,7 @@ pub fn create_monolithic_document(
                     )));
                 }
             },
-            Err(_) => {
+            _ => {
                 // Failed to parse given base URL (perhaps it's a filesystem path?)
                 let path: &Path = Path::new(&target_str);
 

src/url.rs

@@ -147,6 +147,17 @@ pub fn domain_is_within_domain(domain: &str, domain_to_match_against: &str) -> b
     ok
 }
 
+/// Checks if the input is an absolute Windows path (e.g. `C:\dir\page.html` or `C:/dir/page.html`),
+/// which the URL parser would otherwise take for a URL with a one-letter scheme
+pub fn is_windows_drive_path(input: &str) -> bool {
+    let bytes = input.as_bytes();
+
+    bytes.len() >= 3
+        && bytes[0].is_ascii_alphabetic()
+        && bytes[1] == b':'
+        && (bytes[2] == b'\\' || bytes[2] == b'/')
+}
+
 pub fn is_url_and_has_protocol(input: &str) -> bool {
     match Url::parse(input) {
         Ok(parsed_url) => !parsed_url.scheme().is_empty(),

tests/cli/local_files.rs

@@ -127,6 +127,40 @@ document.body.style.color = "red";
         out.assert().code(0);
     }
 
+    #[test]
+    fn local_file_target_input_full_target_path() {
+        let mut cmd = cargo_bin_cmd!(env!("CARGO_PKG_NAME"));
+        // On Windows this is a path that starts with a drive letter, e.g. "C:\...\local-file.html"
+        let path_html = env::current_dir()
+            .unwrap()
+            .join("tests")
+            .join("_data_")
+            .join("basic")
+            .join("local-file.html");
+
+        let out = cmd
+            .arg("-M")
+            .arg("-Ijci")
+            .arg(path_html.as_os_str())
+            .output()
+            .unwrap();
+
+        // STDERR should contain only the target file
+        assert_eq!(
+            String::from_utf8_lossy(&out.stderr),
+            format!(
+                "{file_url_html}\n",
+                file_url_html = Url::from_file_path(fs::canonicalize(&path_html).unwrap()).unwrap(),
+            )
+        );
+
+        // STDOUT should contain HTML from the local file
+        assert!(String::from_utf8_lossy(&out.stdout).contains("<title>Local HTML file</title>"));
+
+        // Exit code should be 0
+        out.assert().code(0);
+    }
+
     #[test]
     fn local_file_url_target_input() {
         let mut cmd = cargo_bin_cmd!(env!("CARGO_PKG_NAME"));

tests/url/is_windows_drive_path.rs

@@ -0,0 +1,69 @@
+//  ██████╗  █████╗ ███████╗███████╗██╗███╗   ██╗ ██████╗
+//  ██╔══██╗██╔══██╗██╔════╝██╔════╝██║████╗  ██║██╔════╝
+//  ██████╔╝███████║███████╗███████╗██║██╔██╗ ██║██║  ███╗
+//  ██╔═══╝ ██╔══██║╚════██║╚════██║██║██║╚██╗██║██║   ██║
+//  ██║     ██║  ██║███████║███████║██║██║ ╚████║╚██████╔╝
+//  ╚═╝     ╚═╝  ╚═╝╚══════╝╚══════╝╚═╝╚═╝  ╚═══╝ ╚═════╝
+
+#[cfg(test)]
+mod passing {
+    use monolith::url;
+
+    #[test]
+    fn backslashes() {
+        assert!(url::is_windows_drive_path(
+            r"C:\Users\Me\Downloads\page.html"
+        ));
+    }
+
+    #[test]
+    fn forward_slashes() {
+        assert!(url::is_windows_drive_path(
+            "C:/Users/Me/Downloads/page.html"
+        ));
+    }
+
+    #[test]
+    fn lowercase_drive_letter() {
+        assert!(url::is_windows_drive_path(r"d:\page.html"));
+    }
+}
+
+//  ███████╗ █████╗ ██╗██╗     ██╗███╗   ██╗ ██████╗
+//  ██╔════╝██╔══██╗██║██║     ██║████╗  ██║██╔════╝
+//  █████╗  ███████║██║██║     ██║██╔██╗ ██║██║  ███╗
+//  ██╔══╝  ██╔══██║██║██║     ██║██║╚██╗██║██║   ██║
+//  ██║     ██║  ██║██║███████╗██║██║ ╚████║╚██████╔╝
+//  ╚═╝     ╚═╝  ╚═╝╚═╝╚══════╝╚═╝╚═╝  ╚═══╝ ╚═════╝
+
+#[cfg(test)]
+mod failing {
+    use monolith::url;
+
+    #[test]
+    fn file_url() {
+        assert!(!url::is_windows_drive_path(
+            "file:///C:/Users/Me/Downloads/page.html"
+        ));
+    }
+
+    #[test]
+    fn http_url() {
+        assert!(!url::is_windows_drive_path("https://example.com/"));
+    }
+
+    #[test]
+    fn unix_path() {
+        assert!(!url::is_windows_drive_path("/home/me/page.html"));
+    }
+
+    #[test]
+    fn relative_path() {
+        assert!(!url::is_windows_drive_path("page.html"));
+    }
+
+    #[test]
+    fn one_letter_scheme() {
+        assert!(!url::is_windows_drive_path("c:page.html"));
+    }
+}

tests/url/mod.rs

@@ -3,5 +3,6 @@ mod create_data_url;
 mod domain_is_within_domain;
 mod get_referer_url;
 mod is_url_and_has_protocol;
+mod is_windows_drive_path;
 mod parse_data_url;
 mod resolve_url;