feat!: empty pathspecs with prefix now are optionally matching the prefix.

Otherwise it's not possible to have the 'no pattern matches everything' case
which is important in conjunction with prefixes and the requirement to
still see everything outside of the prefix.

Author: Byron

gix/src/dirwalk.rs

@@ -17,7 +17,7 @@ pub struct Options {
     emit_empty_directories: bool,
     classify_untracked_bare_repositories: bool,
     emit_collapsed: Option<CollapsedEntriesEmissionMode>,
-    pub(crate) use_prefix: bool,
+    pub(crate) empty_patterns_match_prefix: bool,
 }
 
 /// Construction
@@ -35,7 +35,7 @@ impl Options {
             emit_empty_directories: false,
             classify_untracked_bare_repositories: false,
             emit_collapsed: None,
-            use_prefix: false,
+            empty_patterns_match_prefix: false,
         }
     }
 }
@@ -59,12 +59,13 @@ impl From<Options> for gix_dir::walk::Options {
 }
 
 impl Options {
-    /// If `true`, default `false`, pathspecs and the directory walk itself will be setup to use the [prefix](crate::Repository::prefix).
+    /// If `true`, default `false`, pathspecs and the directory walk itself will be setup to use the [prefix](crate::Repository::prefix)
+    /// if patterns are empty.
     ///
     /// This means that the directory walk will be limited to only what's inside the [repository prefix](crate::Repository::prefix).
     /// By default, the directory walk will see everything.
-    pub fn use_prefix(mut self, toggle: bool) -> Self {
-        self.use_prefix = toggle;
+    pub fn empty_patterns_match_prefix(mut self, toggle: bool) -> Self {
+        self.empty_patterns_match_prefix = toggle;
         self
     }
     /// If `toggle` is `true`, we will stop figuring out if any directory that is a candidate for recursion is also a nested repository,

gix/src/pathspec.rs

@@ -32,13 +32,16 @@ impl<'repo> Pathspec<'repo> {
     /// be used to control where attributes are coming from.
     /// If `inherit_ignore_case` is `true`, the pathspecs may have their ignore-case default overridden to be case-insensitive by default.
     /// This only works towards turning ignore-case for pathspecs on, but won't ever turn that setting off if.
+    /// If `empty_patterns_match_prefix` is `true`, then even empty patterns will match only what's inside of the prefix. Otherwise
+    /// they will match everything.
     ///
     /// ### Deviation
     ///
     /// Pathspecs can declare to be case-insensitive as part of their elements, which is a setting that is now respected for attribute
     /// queries as well.
     pub fn new(
         repo: &'repo Repository,
+        empty_patterns_match_prefix: bool,
         patterns: impl IntoIterator<Item = impl AsRef<BStr>>,
         inherit_ignore_case: bool,
         make_attributes: impl FnOnce() -> Result<gix_worktree::Stack, Box<dyn std::error::Error + Send + Sync + 'static>>,
@@ -49,9 +52,14 @@ impl<'repo> Pathspec<'repo> {
             .map(move |p| parse(p.as_ref(), defaults))
             .collect::<Result<Vec<_>, _>>()?;
         let needs_cache = patterns.iter().any(|p| !p.attributes.is_empty());
+        let prefix = if patterns.is_empty() && !empty_patterns_match_prefix {
+            None
+        } else {
+            repo.prefix()?
+        };
         let search = Search::from_specs(
             patterns,
-            repo.prefix()?,
+            prefix,
             &gix_path::realpath_opts(
                 repo.work_dir().unwrap_or_else(|| repo.git_dir()),
                 repo.options.current_dir_or_empty(),

gix/src/repository/dirwalk.rs

@@ -64,6 +64,7 @@ impl Repository {
             crate::worktree::stack::state::ignore::Source::WorktreeThenIdMappingIfNotSkipped,
         )?;
         let mut pathspec = self.pathspec(
+            options.empty_patterns_match_prefix, /* empty patterns match prefix */
             patterns,
             true, /* inherit ignore case */
             index,
@@ -99,7 +100,7 @@ impl Repository {
                 },
                 excludes: Some(&mut excludes.inner),
                 objects: &self.objects,
-                explicit_traversal_root: (!options.use_prefix).then_some(workdir),
+                explicit_traversal_root: (!options.empty_patterns_match_prefix).then_some(workdir),
             },
             options.into(),
             delegate,

gix/src/repository/pathspec.rs

@@ -8,18 +8,21 @@ impl Repository {
     /// (but also note that `git` does not do that).
     /// `index` may be needed to load attributes which is required only if `patterns` refer to attributes via `:(attr:…)` syntax.
     /// In the same vein, `attributes_source` affects where `.gitattributes` files are read from if pathspecs need to match against attributes.
+    /// If `empty_patterns_match_prefix` is `true`, then even empty patterns will match only what's inside of the prefix. Otherwise
+    /// they will match everything.
     ///
     /// It will be initialized exactly how it would, and attribute matching will be conducted by reading the worktree first if available.
     /// If that is not desirable, consider calling [`Pathspec::new()`] directly.
     #[doc(alias = "Pathspec", alias = "git2")]
     pub fn pathspec(
         &self,
+        empty_patterns_match_prefix: bool,
         patterns: impl IntoIterator<Item = impl AsRef<BStr>>,
         inherit_ignore_case: bool,
         index: &gix_index::State,
         attributes_source: gix_worktree::stack::state::attributes::Source,
     ) -> Result<Pathspec<'_>, crate::pathspec::init::Error> {
-        Pathspec::new(self, patterns, inherit_ignore_case, || {
+        Pathspec::new(self, empty_patterns_match_prefix, patterns, inherit_ignore_case, || {
             self.attributes_only(index, attributes_source)
                 .map(AttributeStack::detach)
                 .map_err(Into::into)

gix/src/worktree/mod.rs

@@ -219,6 +219,8 @@ pub mod pathspec {
         /// Configure pathspecs `patterns` to be matched against, with pathspec attributes read from the worktree and then from the index
         /// if needed.
         ///
+        /// Note that the `empty_patterns_match_prefix` flag of the [parent method](crate::Repository::pathspec()) defaults to `true`.
+        ///
         /// ### Deviation
         ///
         /// Pathspec attributes match case-insensitively by default if the underlying filesystem is configured that way.
@@ -244,6 +246,7 @@ pub mod pathspec {
                 .map_err(|err| Error::Init(crate::pathspec::init::Error::Defaults(err.into())))?
                 .unwrap_or(gitoxide::Pathspec::INHERIT_IGNORE_CASE_DEFAULT);
             Ok(self.parent.pathspec(
+                true, /* empty patterns match prefix */
                 patterns,
                 inherit_ignore_case,
                 &index,

gix/tests/repository/pathspec.rs

@@ -9,7 +9,9 @@ fn defaults_are_taken_from_repo_config() -> crate::Result {
     repo.config_snapshot_mut()
         .set_value(&gitoxide::Pathspec::ICASE, "true")?;
     let inherit_ignore_case = true;
+    let empty_pathspecs_match_prefix = true;
     let mut pathspec = repo.pathspec(
+        empty_pathspecs_match_prefix,
         [
             "hi",
             ":!hip",