From c335f3e60d9fd79a930303ef9a341c913dd4091b Mon Sep 17 00:00:00 2001
From: Nikita Galaiko <nikita@galaiko.rocks>
Date: Tue, 25 Jul 2023 14:26:15 +0200
Subject: [PATCH] smarter defautl branch name

---
 src-tauri/src/dedup.rs                | 43 +++++++++++++++++++++++++++
 src-tauri/src/lib.rs                  |  1 +
 src-tauri/src/main.rs                 |  1 +
 src-tauri/src/virtual_branches/mod.rs | 11 ++++++-
 4 files changed, 55 insertions(+), 1 deletion(-)
 create mode 100644 src-tauri/src/dedup.rs

diff --git a/src-tauri/src/dedup.rs b/src-tauri/src/dedup.rs
new file mode 100644
index 000000000..503b6f3b7
--- /dev/null
+++ b/src-tauri/src/dedup.rs
@@ -0,0 +1,43 @@
+use std::collections::HashSet;
+
+// dedup makes sure that _new_ is not in _existing_ by adding a number to it.
+// the number is increased until the name is unique.
+pub fn dedup(existing: &[&str], new: &str) -> String {
+    let used_numbers = existing
+        .iter()
+        .filter(|x| x.starts_with(new))
+        .filter_map(|x| {
+            x.strip_prefix(new)
+                .map(|x| x.trim_start())
+                .map(|x| x.parse::<i32>().unwrap_or(-1))
+        })
+        .collect::<HashSet<_>>();
+    if used_numbers.is_empty() || !used_numbers.contains(&-1) {
+        new.to_string()
+    } else {
+        // pick first unused number
+        let mut number = 1;
+        while used_numbers.contains(&number) {
+            number += 1;
+        }
+        format!("{} {}", new, number)
+    }
+}
+
+#[test]
+fn test_dedup() {
+    vec![
+        (vec!["foo", "foo 2"], "foo", "foo 1"),
+        (vec!["foo", "foo 1", "foo 2"], "foo", "foo 3"),
+        (vec!["foo", "foo 1", "foo 2"], "foo 1", "foo 1 1"),
+        (vec!["foo", "foo 1", "foo 2"], "foo 2", "foo 2 1"),
+        (vec!["foo", "foo 1", "foo 2"], "foo 3", "foo 3"),
+        (vec!["foo 2"], "foo", "foo"),
+        (vec!["foo", "foo 1", "foo 2", "foo 4"], "foo", "foo 3"),
+    ]
+    .iter()
+    .enumerate()
+    .for_each(|(i, (existing, new, expected))| {
+        assert_eq!(dedup(existing, new), expected.to_string(), "test {}", i + 1);
+    });
+}
diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index 84b717f7a..ce1e116c8 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -4,6 +4,7 @@ extern crate scopeguard;
 pub mod app;
 pub mod bookmarks;
 pub mod database;
+pub mod dedup;
 pub mod deltas;
 pub mod events;
 pub mod files;
diff --git a/src-tauri/src/main.rs b/src-tauri/src/main.rs
index 90a2b1d90..b5a673d15 100644
--- a/src-tauri/src/main.rs
+++ b/src-tauri/src/main.rs
@@ -1,6 +1,7 @@
 #[macro_use(defer)]
 extern crate scopeguard;
 
+mod dedup;
 mod app;
 mod assets;
 mod bookmarks;
diff --git a/src-tauri/src/virtual_branches/mod.rs b/src-tauri/src/virtual_branches/mod.rs
index 32f88d769..274537143 100644
--- a/src-tauri/src/virtual_branches/mod.rs
+++ b/src-tauri/src/virtual_branches/mod.rs
@@ -21,6 +21,7 @@ pub use iterator::BranchIterator as Iterator;
 use uuid::Uuid;
 
 use crate::{
+    dedup::dedup,
     gb_repository,
     project_repository::{self, conflicts, diff},
     reader, sessions,
@@ -1137,7 +1138,15 @@ pub fn create_virtual_branch(
         .name
         .as_ref()
         .map(|name| name.to_string())
-        .unwrap_or_else(|| format!("Virtual branch {}", all_virtual_branches.len() + 1));
+        .unwrap_or_else(|| {
+            dedup(
+                &all_virtual_branches
+                    .iter()
+                    .map(|b| b.name.as_str())
+                    .collect::<Vec<_>>(),
+                "Virtual branch",
+            )
+        });
 
     let mut branch = Branch {
         id: Uuid::new_v4().to_string(),