Fix 576 stash apply conflicts (#578)

* unittest that applying with conflicts errors out and prepare for stash apply to allow creating conflicts for later
* mark conflicting items

Author: Stephan Dilly

asyncgit/src/sync/stash.rs

@@ -1,6 +1,9 @@
 use super::{utils::repo, CommitId};
 use crate::error::{Error, Result};
-use git2::{Oid, Repository, StashFlags};
+use git2::{
+    build::CheckoutBuilder, Oid, Repository, StashApplyOptions,
+    StashFlags,
+};
 use scopetime::scope_time;
 
 ///
@@ -45,14 +48,20 @@ pub fn stash_drop(repo_path: &str, stash_id: CommitId) -> Result<()> {
 pub fn stash_apply(
     repo_path: &str,
     stash_id: CommitId,
+    allow_conflicts: bool,
 ) -> Result<()> {
     scope_time!("stash_apply");
 
     let mut repo = repo(repo_path)?;
 
     let index = get_stash_index(&mut repo, stash_id.get_oid())?;
 
-    repo.stash_apply(index, None)?;
+    let mut checkout = CheckoutBuilder::new();
+    checkout.allow_conflicts(allow_conflicts);
+
+    let mut opt = StashApplyOptions::default();
+    opt.checkout_options(checkout);
+    repo.stash_apply(index, Some(&mut opt))?;
 
     Ok(())
 }
@@ -109,7 +118,11 @@ mod tests {
     use super::*;
     use crate::sync::{
         commit, get_commit_files, get_commits_info, stage_add_file,
-        tests::{debug_cmd_print, get_statuses, repo_init},
+        staging::repo_write_file,
+        tests::{
+            debug_cmd_print, get_statuses, repo_init,
+            write_commit_file,
+        },
     };
     use std::{fs::File, io::Write, path::Path};
 
@@ -211,4 +224,66 @@ mod tests {
 
         Ok(())
     }
+
+    #[test]
+    fn test_stash_apply_conflict() {
+        let (_td, repo) = repo_init().unwrap();
+        let root = repo.path().parent().unwrap();
+        let repo_path = root.as_os_str().to_str().unwrap();
+
+        repo_write_file(&repo, "test.txt", "test").unwrap();
+
+        let id =
+            stash_save(repo_path, Some("foo"), true, false).unwrap();
+
+        repo_write_file(&repo, "test.txt", "foo").unwrap();
+
+        let res = stash_apply(repo_path, id, false);
+
+        assert!(res.is_err());
+    }
+
+    #[test]
+    fn test_stash_apply_conflict2() {
+        let (_td, repo) = repo_init().unwrap();
+        let root = repo.path().parent().unwrap();
+        let repo_path = root.as_os_str().to_str().unwrap();
+
+        write_commit_file(&repo, "test.txt", "test", "c1");
+
+        repo_write_file(&repo, "test.txt", "test2").unwrap();
+
+        let id =
+            stash_save(repo_path, Some("foo"), true, false).unwrap();
+
+        repo_write_file(&repo, "test.txt", "test3").unwrap();
+
+        let res = stash_apply(repo_path, id, false);
+
+        assert!(res.is_err());
+    }
+
+    #[test]
+    fn test_stash_apply_creating_conflict() {
+        let (_td, repo) = repo_init().unwrap();
+        let root = repo.path().parent().unwrap();
+        let repo_path = root.as_os_str().to_str().unwrap();
+
+        write_commit_file(&repo, "test.txt", "test", "c1");
+
+        repo_write_file(&repo, "test.txt", "test2").unwrap();
+
+        let id =
+            stash_save(repo_path, Some("foo"), true, false).unwrap();
+
+        repo_write_file(&repo, "test.txt", "test3").unwrap();
+
+        let res = stash_apply(repo_path, id, false);
+
+        assert!(res.is_err());
+
+        let res = stash_apply(repo_path, id, true);
+
+        assert!(res.is_ok());
+    }
 }

asyncgit/src/sync/status.rs

@@ -18,6 +18,8 @@ pub enum StatusItemType {
     Renamed,
     ///
     Typechange,
+    ///
+    Conflicted,
 }
 
 impl From<Status> for StatusItemType {
@@ -30,6 +32,8 @@ impl From<Status> for StatusItemType {
             Self::Renamed
         } else if s.is_index_typechange() || s.is_wt_typechange() {
             Self::Typechange
+        } else if s.is_conflicted() {
+            Self::Conflicted
         } else {
             Self::Modified
         }

src/components/filetree.rs

@@ -142,6 +142,7 @@ impl FileTreeComponent {
             StatusItemType::Deleted => '-',
             StatusItemType::Renamed => 'R',
             StatusItemType::Typechange => ' ',
+            StatusItemType::Conflicted => '!',
         }
     }
 

src/tabs/stashlist.rs

@@ -57,7 +57,7 @@ impl StashList {
 
     fn apply_stash(&mut self) {
         if let Some(e) = self.list.selected_entry() {
-            match sync::stash_apply(CWD, e.id) {
+            match sync::stash_apply(CWD, e.id, false) {
                 Ok(_) => {
                     self.queue
                         .borrow_mut()

src/ui/style.rs

@@ -135,6 +135,9 @@ impl Theme {
             StatusItemType::Renamed => {
                 Style::default().fg(self.diff_file_moved)
             }
+            StatusItemType::Conflicted => Style::default()
+                .fg(self.diff_file_modified)
+                .add_modifier(Modifier::BOLD),
             StatusItemType::Typechange => Style::default(),
         };