feat: add Repository::blob_merge_options() to obtain options for merging blobs and Repository::diff_algorithm()

Author: Byron

gix/src/repository/config/mod.rs

@@ -120,6 +120,14 @@ impl crate::Repository {
     pub fn object_hash(&self) -> gix_hash::Kind {
         self.config.object_hash
     }
+
+    /// Return the algorithm to perform diffs or merges with.
+    ///
+    /// In case of merges, a diff is performed under the hood in order to learn which hunks need merging.
+    #[cfg(feature = "blob-diff")]
+    pub fn diff_algorithm(&self) -> Result<gix_diff::blob::Algorithm, config::diff::algorithm::Error> {
+        self.config.diff_algorithm()
+    }
 }
 
 mod branch;

gix/src/repository/merge.rs

@@ -1,7 +1,8 @@
 use crate::config::cache::util::ApplyLeniencyDefault;
 use crate::config::tree;
-use crate::repository::merge_resource_cache;
+use crate::repository::{blob_merge_options, merge_resource_cache};
 use crate::Repository;
+use gix_merge::blob::builtin_driver::text;
 use std::borrow::Cow;
 
 /// Merge-utilities
@@ -53,4 +54,29 @@ impl Repository {
         let drivers = self.config.merge_drivers()?;
         Ok(gix_merge::blob::Platform::new(filter, mode, attrs, drivers, options))
     }
+
+    /// Return options for use with [`gix_merge::blob::PlatformRef::merge()`].
+    pub fn blob_merge_options(&self) -> Result<gix_merge::blob::platform::merge::Options, blob_merge_options::Error> {
+        Ok(gix_merge::blob::platform::merge::Options {
+            is_virtual_ancestor: false,
+            resolve_binary_with: None,
+            text: gix_merge::blob::builtin_driver::text::Options {
+                diff_algorithm: self.config.diff_algorithm()?,
+                conflict: text::Conflict::Keep {
+                    style: self
+                        .config
+                        .resolved
+                        .string(&tree::Merge::CONFLICT_STYLE)
+                        .map(|value| {
+                            tree::Merge::CONFLICT_STYLE
+                                .try_into_conflict_style(value)
+                                .with_lenient_default(self.config.lenient_config)
+                        })
+                        .transpose()?
+                        .unwrap_or_default(),
+                    marker_size: text::Conflict::DEFAULT_MARKER_SIZE,
+                },
+            },
+        })
+    }
 }

gix/src/repository/mod.rs

@@ -58,6 +58,20 @@ mod submodule;
 mod thread_safe;
 mod worktree;
 
+///
+#[cfg(feature = "blob-merge")]
+pub mod blob_merge_options {
+    /// The error returned by [Repository::blob_merge_options()](crate::Repository::blob_merge_options()).
+    #[derive(Debug, thiserror::Error)]
+    #[allow(missing_docs)]
+    pub enum Error {
+        #[error(transparent)]
+        DiffAlgorithm(#[from] crate::config::diff::algorithm::Error),
+        #[error(transparent)]
+        ConflictStyle(#[from] crate::config::key::GenericErrorWithValue),
+    }
+}
+
 ///
 #[cfg(feature = "blob-merge")]
 pub mod merge_resource_cache {