From 0acb3505ffe71718cb3b6b0e957cc921ea9ce880 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michael=20Mur=C3=A9?= <batolettre@gmail.com>
Date: Sun, 27 Sep 2020 23:14:51 +0200
Subject: [PATCH] repo: implement GetCoreEditor for go-git

---
 repository/gogit.go | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/repository/gogit.go b/repository/gogit.go
index 6d3aede91ea7ffb4b26d49b81693546f97ad3c7e..aac89d4bd626ef1aa52e86543e5ed7d49933366e 100644
--- a/repository/gogit.go
+++ b/repository/gogit.go
@@ -208,8 +208,30 @@ func (repo *GoGitRepo) GetUserEmail() (string, error) {
 
 // GetCoreEditor returns the name of the editor that the user has used to configure git.
 func (repo *GoGitRepo) GetCoreEditor() (string, error) {
+	// See https://git-scm.com/docs/git-var
+	// The order of preference is the $GIT_EDITOR environment variable, then core.editor configuration, then $VISUAL, then $EDITOR, and then the default chosen at compile time, which is usually vi.
 
-	panic("implement me")
+	if val, ok := os.LookupEnv("GIT_EDITOR"); ok {
+		return val, nil
+	}
+
+	val, err := repo.AnyConfig().ReadString("core.editor")
+	if err == nil && val != "" {
+		return val, nil
+	}
+	if err != nil && err != ErrNoConfigEntry {
+		return "", err
+	}
+
+	if val, ok := os.LookupEnv("VISUAL"); ok {
+		return val, nil
+	}
+
+	if val, ok := os.LookupEnv("EDITOR"); ok {
+		return val, nil
+	}
+
+	return "vi", nil
 }
 
 // GetRemotes returns the configured remotes repositories.