push: respect branch.*.merge when push default is upstream

asyncgit: config add push default strategy config

Author: vlad-anger

asyncgit/src/sync/config.rs

@@ -62,6 +62,54 @@ pub fn untracked_files_config_repo(
 	Ok(ShowUntrackedFilesConfig::All)
 }
 
+// see https://git-scm.com/docs/git-config#Documentation/git-config.txt-pushdefault
+/// represent `push.default` git config
+pub enum PushDefaultStrategyConfig {
+	Nothing,
+	Current,
+	Upstream,
+	Simple,
+	Matching,
+}
+
+impl Default for PushDefaultStrategyConfig {
+	fn default() -> Self {
+		Self::Simple
+	}
+}
+
+impl<'a> TryFrom<&'a str> for PushDefaultStrategyConfig {
+	type Error = crate::Error;
+	fn try_from(
+		value: &'a str,
+	) -> std::result::Result<Self, Self::Error> {
+		match value {
+			"nothing" => Ok(Self::Nothing),
+			"current" => Ok(Self::Current),
+			"upstream" => Ok(Self::Upstream),
+			"simple" => Ok(Self::Simple),
+			"matching" => Ok(Self::Matching),
+			_ => Err(crate::Error::Generic(format!(
+				"{value} is incorrect push.default"
+			))),
+		}
+	}
+}
+
+pub fn push_default_strategy_config_repo(
+	repo: &Repository,
+) -> Result<PushDefaultStrategyConfig> {
+	(get_config_string_repo(repo, "push.default")?).map_or_else(
+		|| Ok(PushDefaultStrategyConfig::default()),
+		|entry_str| {
+			Ok(PushDefaultStrategyConfig::try_from(
+				entry_str.as_str(),
+			)
+			.unwrap_or_default())
+		},
+	)
+}
+
 ///
 pub fn untracked_files_config(
 	repo_path: &RepoPath,

asyncgit/src/sync/remotes/push.rs

@@ -3,7 +3,12 @@ use crate::{
 	progress::ProgressPercent,
 	sync::{
 		branch::branch_set_upstream_after_push,
+		config::{
+			push_default_strategy_config_repo,
+			PushDefaultStrategyConfig,
+		},
 		cred::BasicAuthCredential,
+		get_branch_upstream_merge,
 		remotes::{proxy_auto, Callbacks},
 		repository::repo,
 		CommitId, RepoPath,
@@ -145,6 +150,9 @@ pub fn push_raw(
 	let repo = repo(repo_path)?;
 	let mut remote = repo.find_remote(remote)?;
 
+	let push_default_strategy =
+		push_default_strategy_config_repo(&repo)?;
+
 	let mut options = PushOptions::new();
 	options.proxy_options(proxy_auto());
 
@@ -163,9 +171,23 @@ pub fn push_raw(
 		PushType::Tag => "tags",
 	};
 
-	let branch_name =
+	let mut push_ref =
 		format!("{branch_modifier}refs/{ref_type}/{branch}");
-	remote.push(&[branch_name.as_str()], Some(&mut options))?;
+
+	if !delete
+		&& matches!(
+			push_default_strategy,
+			PushDefaultStrategyConfig::Upstream
+		) {
+		if let Ok(Some(branch_upstream_merge)) =
+			get_branch_upstream_merge(repo_path, branch)
+		{
+			push_ref.push_str(&format!(":{branch_upstream_merge}"));
+		}
+	}
+
+	log::debug!("push to: {push_ref}");
+	remote.push(&[push_ref], Some(&mut options))?;
 
 	if let Some((reference, msg)) =
 		callbacks.get_stats()?.push_rejected_msg