fix hg status path relativization in tests on Windows

Summary:
Fix the `test_status()` function to properly canonicalize the input paths, so
that it works successfully on Windows.  Previously this function would fail on
Windows as some paths would end up as UNC-style paths and some would be plain
paths, causing the equality comparison to fail even though the paths were
equivalent.  This canonicalizes the repo path so that they both use the same
format.

Reviewed By: quark-zju

Differential Revision: D20662921

fbshipit-source-id: fdd36bac755f9694b4a482615d3dca43ff21e05e

Author: simpkins

eden/scm/lib/edenfs-client/src/path_relativizer.rs

@@ -86,6 +86,12 @@ pub struct PathRelativizer {
 
 /// Utility for computing a relativized path for a file in an Hg repository given the user's cwd
 /// and specified value for --repository/-R, if any.
+///
+/// Note: the caller is responsible for normalizing the repo_root and cwd parameters ahead of time.
+/// If these are specified in different formats (e.g., on Windows one is a UNC path and the other
+/// is not), then this function will not produce expected results.  Unfortunately the Rust library
+/// does not provide a mechanism for normalizing paths.  The best thing for callers to do for now
+/// is probably to call Path::canonicalize() if they expect that the paths do exist on disk.
 impl PathRelativizer {
     /// `cwd` corresponds to getcwd(2) while `repo_root` is the absolute path specified via
     /// --repository/-R, or failing that, the Hg repo that contains `cwd`.
@@ -95,7 +101,7 @@ impl PathRelativizer {
 
     fn new_impl(cwd: &Path, repo_root: &Path) -> PathRelativizer {
         use self::PathRelativizerConfig::*;
-        let config = if cwd.starts_with(repo_root) {
+        let config = if cwd.starts_with(&repo_root) {
             CwdUnderRepo {
                 relative_cwd: relativize(repo_root, cwd),
             }
@@ -144,6 +150,14 @@ mod test {
         check("/foo/bar/baz", "/foo/BAR/BAZ", "../../BAR/BAZ");
     }
 
+    #[test]
+    fn relativize_platform_absolute_paths() {
+        // This test with Windows-style absolute paths on Windows, and Unix-style path on Unix
+        let cwd = Path::new(".").canonicalize().unwrap();
+        let result = relativize(&cwd, &cwd.join("a").join("b"));
+        assert_eq!(result, Path::new("a").join("b"));
+    }
+
     #[test]
     fn relativize_path_from_repo_when_cwd_is_repo_root() {
         let repo_root = Path::new("/home/zuck/tfb");

eden/scm/lib/edenfs-client/src/status.rs

@@ -813,6 +813,7 @@ mod test {
     /// focuses on exercising the display logic under various scenarios.
     fn test_status(test_case: StatusTestCase<'_>) {
         let repo_root = generate_fixture(test_case.files);
+        let repo_root_path = repo_root.path().canonicalize().unwrap();
         let mut all_args: Vec<String> = vec![
             "--cwd".to_owned(),
             repo_root.path().to_str().unwrap().to_string(),
@@ -835,7 +836,7 @@ mod test {
 
         let relativizer = HgStatusPathRelativizer::new(
             print_config.root_relative,
-            PathRelativizer::new(hg_args.cwd, repo_root.path()),
+            PathRelativizer::new(hg_args.cwd, repo_root_path),
         );
         let tin = "".as_bytes();
         let tout = Vec::new();