fix(status): rudimentary support for filenames with spaces

The regex in `StatusEntry::try_from()` was mistaken parsing status lines for
files with spaces in such a way to discard the first word in the path name.
This attempts to make that less likely by making the regex more specific, but
I don't think it's really unavoidable without completely reworking this part
of the code to be less flexible. eg if we parsed each of the 1/2/u statuses
separately, then we could be more specific about how many fields we need to
match/capture for each option.

I suspect that this issue was already rare, and that this fix will make it even
moreso. Given that, I feel like a more robust/complex fix probably isn't
warranted. With this fix, files like "r101 project.txt" or "Coffee notes.txt"
will work, but "R101 project.txt" or "coffee notes.txt" ("R101" looks like a
"change score", and "coffee" is a valid hex value.)

The options that come to mind to tighten this up further:
- parse each 1/2/u status separately, making field counts and patterns more
  discrete
- require a minimum number of chars in an object ID (on my Mac, the longest
  "hex word" in /usr/share/dict/words is 7 chars, so requiring at least 8 chars
  in an OID would eliminate "coffee"-style false positives)

CHANGELOG.md

@@ -18,6 +18,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - BREAKING (#1128) Arguments/revsets passed to `git sync` are now resolved to their respective stacks.
   - This allows `git sync my-branch` to work as expected, instead of needing to use `git sync 'stack(my-branch)'`. The behavior of `git sync` when called without arguments is not affected by this change. If you rely on the previous behavior, please use `git move -x <commit(s)/revset> -d 'main()'` instead.
 
+### Fixed
+
+- (#1127) Improved support for files with spaces in their name.
+
 
 ## [v0.8.0] - 2023-08-27
 

git-branchless-lib/src/git/status.rs

@@ -200,7 +200,8 @@ impl TryFrom<&[u8]> for StatusEntry {
                 r#"[\w.]+ "#,                                                // Submodule state.
                 r#"(\d{6} ){2,3}(?P<working_copy_filemode>\d{6}) "#,         // HEAD, Index, and Working Copy file modes;
                                                                              // or stage1, stage2, stage3, and working copy file modes.
-                r#"([\w\d]+ ){2,3}"#,                                        // HEAD and Index object IDs, and optionally the rename/copy score.
+                r#"([a-f\d]+ ){2,3}([CR]\d{1,3} )?"#,                        // HEAD and Index object IDs, and optionally the rename/copy score;
+                                                                             // or stage1, stage2, and stage3 object IDs.
                 r#"(?P<path>[^\x00]+)(\x00(?P<orig_path>[^\x00]+))?$"#       // Path and original path (for renames/copies).
             ))
             .expect("porcelain v2 status line regex");

git-branchless-lib/tests/test_status.rs

@@ -20,6 +20,19 @@ fn test_parse_status_line() {
             }
         );
 
+    assert_eq!(
+            StatusEntry::try_from(
+                "1 .M N... 100644 100644 100644 51fcbe2362663a19d132767b69c2c7829023f3da 51fcbe2362663a19d132767b69c2c7829023f3da filename with spaces.rs".as_bytes(),
+            ).unwrap(),
+            StatusEntry {
+                index_status: FileStatus::Unmodified,
+                working_copy_status: FileStatus::Modified,
+                path: "filename with spaces.rs".into(),
+                orig_path: None,
+                working_copy_file_mode: FileMode::Blob,
+            }
+        );
+
     assert_eq!(
             StatusEntry::try_from(
                 "1 A. N... 100755 100755 100755 51fcbe2362663a19d132767b69c2c7829023f3da 51fcbe2362663a19d132767b69c2c7829023f3da repo.rs".as_bytes(),
@@ -33,6 +46,19 @@ fn test_parse_status_line() {
             }
         );
 
+    assert_eq!(
+            StatusEntry::try_from(
+                "1 A. N... 100755 100755 100755 51fcbe2362663a19d132767b69c2c7829023f3da 51fcbe2362663a19d132767b69c2c7829023f3da filename with spaces.rs".as_bytes(),
+            ).unwrap(),
+            StatusEntry {
+                index_status: FileStatus::Added,
+                working_copy_status: FileStatus::Unmodified,
+                path: "filename with spaces.rs".into(),
+                orig_path: None,
+                working_copy_file_mode: FileMode::BlobExecutable,
+            }
+        );
+
     let entry: StatusEntry = StatusEntry::try_from(
             "2 RD N... 100644 100644 100644 9daeafb9864cf43055ae93beb0afd6c7d144bfa4 9daeafb9864cf43055ae93beb0afd6c7d144bfa4 R100 new_file.rs\x00old_file.rs".as_bytes(),
         ).unwrap();
@@ -63,6 +89,19 @@ fn test_parse_status_line() {
                 working_copy_file_mode: FileMode::BlobExecutable,
             }
         );
+
+    assert_eq!(
+            StatusEntry::try_from(
+                "u A. N... 100755 100755 100755 100755 51fcbe2362663a19d132767b69c2c7829023f3da 51fcbe2362663a19d132767b69c2c7829023f3da 9daeafb9864cf43055ae93beb0afd6c7d144bfa4 filename with spaces.rs".as_bytes(),
+            ).unwrap(),
+            StatusEntry {
+                index_status: FileStatus::Unmerged,
+                working_copy_status: FileStatus::Unmodified,
+                path: "filename with spaces.rs".into(),
+                orig_path: None,
+                working_copy_file_mode: FileMode::BlobExecutable,
+            }
+        );
 }
 
 #[test]

git-branchless/tests/test_amend.rs

@@ -412,6 +412,39 @@ fn test_amend_head() -> eyre::Result<()> {
     Ok(())
 }
 
+#[test]
+fn test_amend_head_with_file_with_space() -> eyre::Result<()> {
+    let git = make_git()?;
+
+    if !git.supports_committer_date_is_author_date()? {
+        return Ok(());
+    }
+
+    git.init_repo()?;
+    git.detach_head()?;
+    git.commit_file("test file with space", 1)?;
+    git.write_file_txt("test file with space", "updated contents")?;
+
+    {
+        let (stdout, _stderr) = git.branchless("amend", &[])?;
+        insta::assert_snapshot!(stdout, @r###"
+        branchless: running command: <git-executable> reset 5ccdda3c1e0dca9aa58634b37cfa9cac09e3975b
+        Amended with 1 uncommitted change.
+        "###);
+    }
+
+    {
+        let stdout = git.smartlog()?;
+        insta::assert_snapshot!(stdout, @r###"
+        O f777ecc (master) create initial.txt
+        |
+        @ 5ccdda3 create test file with space.txt
+        "###);
+    }
+
+    Ok(())
+}
+
 #[test]
 #[cfg(unix)]
 fn test_amend_executable() -> eyre::Result<()> {