git: enable libgit2's OpenSSH feature

Cargo.toml

@@ -46,7 +46,9 @@ dirs = "5.0.1"
 dunce = "1.0.5"
 either = "1.13.0"
 futures = "0.3.31"
-git2 = { git = "https://github.com/bnjmnt4n/git2-rs.git", rev = "8614b5d", features = [
+git2 = { git = "https://github.com/bnjmnt4n/git2-rs.git", rev = "8614b5d", default-features = false, features = [
+    "https",
+    "ssh-openssh",
     # Do *not* disable this feature even if you'd like dynamic linking. Instead,
     # set the environment variable `LIBGIT2_NO_VENDOR=1` if dynamic linking must
     # be used (this will override the Cargo feature), and allow static linking

cli/src/command_error.rs

@@ -605,8 +605,8 @@ jj currently does not support partial clones. To use jj with this repository, tr
                  successfully load certificates. Try setting it to the path of a directory that \
                  contains a `.ssh` directory."
             } else {
-                "Jujutsu uses libssh2, which doesn't respect ~/.ssh/config. Does `ssh -F \
-                 /dev/null` to the host work?"
+                "There was an error creating an SSH connection. Does `ssh -F /dev/null` to the \
+                 host work?"
             };
 
             user_error_with_hint(err, hint)

flake.nix

@@ -77,7 +77,7 @@
         [
           openssl
           libgit2
-          libssh2
+          openssh
         ]
         ++ lib.optionals stdenv.isDarwin [
           darwin.apple_sdk.frameworks.Security
@@ -95,7 +95,6 @@
       ];
 
       env = {
-        LIBSSH2_SYS_USE_PKG_CONFIG = "1";
         RUST_BACKTRACE = 1;
       };
     in {