cli: test delegate convergence

If a delegate is in a diverged state from the canonical head, ensure
that they can easily reset to another delegate's head to converge
again.

Signed-off-by: Fintan Halpenny <fintan.halpenny@gmail.com>
X-Clacks-Overhead: GNU Terry Pratchett

radicle-cli/examples/git/git-push-converge.md

@@ -0,0 +1,111 @@
+In this scenario we check that we can easily reset our canonical head to the
+head of another delegate when there is divergence between the 3 delegates.
+
+First we add our new delegates, Bob & Eve, to our repo, while also setting the
+`threshold` to `2`:
+
+``` ~alice
+$ rad id update --title "Add Bob & Eve" --description "" --delegate did:key:z6Mkt67GdsW7715MEfRuP4pSZxJRJh6kj6Y48WRqVv4N1tRk --delegate did:key:z6Mkux1aUQD2voWWukVb5nNUR7thrHveQG4pDQua8nVhib7Z --threshold 2 --repo rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji -q
+73bd6ea3f88eb0687afd13ee13bfb31a9eb0ccd2
+```
+
+Bob and Eve will fetch the changes to ensure they hear about their delegate
+responsibilities:
+
+``` ~bob
+$ rad sync --fetch
+✓ Fetching rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji from z6MknSL…StBU8Vi..
+✓ Fetching rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji from z6Mkux1…nVhib7Z..
+✓ Fetched repository from 2 seed(s)
+```
+
+``` ~eve
+$ rad sync --fetch
+✓ Fetching rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji from z6Mkt67…v4N1tRk..
+✓ Fetching rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji from z6MknSL…StBU8Vi..
+✓ Fetched repository from 2 seed(s)
+```
+
+To demonstrate the divergence, Alice, Bob, and Eve will all create a new change,
+pushing to their `rad` remote -- but they won't sync to the network just yet:
+
+``` ~alice
+$ git commit -m "Alice's commit" --allow-empty -q
+$ git push rad -o no-sync
+$ git ls-remote rad
+f2de534b5e81d7c6e2dcaf58c3dd91573c0a0354	refs/heads/master
+```
+
+``` ~bob
+$ git commit -m "Bob's commit" --allow-empty -q
+$ git push rad -o no-sync
+$ git ls-remote rad
+f2de534b5e81d7c6e2dcaf58c3dd91573c0a0354	refs/heads/master
+```
+
+``` ~eve
+$ git commit -m "Eve's commit" --allow-empty -q
+$ git push rad -o no-sync
+$ git ls-remote rad
+f2de534b5e81d7c6e2dcaf58c3dd91573c0a0354	refs/heads/master
+```
+
+Alice adds Bob and Eve as remotes and starts to notice that the `no quorum was
+found` error is showing up:
+
+``` ~alice
+$ rad remote add did:key:z6Mkt67GdsW7715MEfRuP4pSZxJRJh6kj6Y48WRqVv4N1tRk --name bob
+✓ Follow policy updated for z6Mkt67GdsW7715MEfRuP4pSZxJRJh6kj6Y48WRqVv4N1tRk (bob)
+✓ Fetching rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji from z6Mkt67…v4N1tRk..
+✗ Fetching rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji from z6Mkux1…nVhib7Z.. error: no quorum was found
+✓ Remote bob added
+✓ Remote-tracking branch bob/master created for z6Mkt67…v4N1tRk
+$ rad remote add did:key:z6Mkux1aUQD2voWWukVb5nNUR7thrHveQG4pDQua8nVhib7Z --name eve
+✓ Follow policy updated for z6Mkux1aUQD2voWWukVb5nNUR7thrHveQG4pDQua8nVhib7Z (eve)
+✗ Fetching rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji from z6Mkt67…v4N1tRk.. error: no quorum was found
+✗ Fetching rad:z42hL2jL4XNk6K8oHQaSWfMgCL7ji from z6Mkux1…nVhib7Z.. error: no quorum was found
+✓ Remote eve added
+✓ Remote-tracking branch eve/master created for z6Mkux1…nVhib7Z
+```
+
+Alice does indeed have Bob and Eve's references, however, a new canonical
+`refs/heads/master` cannot be decided while they're out of quorum. This can be
+remedied by the delegates agreeing upon which way to move forward. In this case,
+Alice resets her `master` to `bob/master`:
+
+``` ~alice
+$ git reset bob/master --hard
+HEAD is now at 0801f02 Bob's commit
+```
+
+She can then force push to update the canonical head to the new agreed upon
+commit:
+
+``` ~alice (stderr)
+$ git push rad -f
+✓ Canonical head updated to 0801f020f11a08ec7a96d1710ec24e5e005499d1
+✓ Synced with 2 node(s)
+To rad://z42hL2jL4XNk6K8oHQaSWfMgCL7ji/z6MknSLrJoTcukLrE435hVNQT4JUhbvWLX4kUzqkEStBU8Vi
+ + d09e634...0801f02 master -> master (forced update)
+```
+
+We can convince ourselves that the canonical branch has indeed changed by using
+`git ls-remote` for each of the delegates:
+
+``` ~alice
+$ git ls-remote rad
+0801f020f11a08ec7a96d1710ec24e5e005499d1	refs/heads/master
+```
+
+``` ~bob
+$ git ls-remote rad
+0801f020f11a08ec7a96d1710ec24e5e005499d1	refs/heads/master
+```
+
+``` ~eve
+$ git ls-remote rad
+0801f020f11a08ec7a96d1710ec24e5e005499d1	refs/heads/master
+```
+
+
+

radicle-cli/tests/commands.rs

@@ -2441,6 +2441,57 @@ fn git_push_diverge() {
         .unwrap();
 }
 
+#[test]
+fn git_push_converge() {
+    let mut environment = Environment::new();
+    let alice = environment.node(Config::test(Alias::new("alice")));
+    let bob = environment.node(Config::test(Alias::new("bob")));
+    let eve = environment.node(Config::test(Alias::new("eve")));
+    let working = environment.tmp().join("working");
+    let acme = RepoId::from_str("z42hL2jL4XNk6K8oHQaSWfMgCL7ji").unwrap();
+
+    fixtures::repository(working.join("alice"));
+
+    test(
+        "examples/rad-init.md",
+        working.join("alice"),
+        Some(&alice.home),
+        [],
+    )
+    .unwrap();
+
+    let alice = alice.spawn();
+    let mut bob = bob.spawn();
+    let mut eve = eve.spawn();
+
+    bob.connect(&alice).connect(&eve).converge([&alice]);
+    eve.connect(&alice).converge([&alice]);
+    bob.fork(acme, working.join("bob")).unwrap();
+    eve.fork(acme, working.join("eve")).unwrap();
+    alice.has_remote_of(&acme, &bob.id);
+    alice.has_remote_of(&acme, &eve.id);
+
+    formula(&environment.tmp(), "examples/git/git-push-converge.md")
+        .unwrap()
+        .home(
+            "alice",
+            working.join("alice"),
+            [("RAD_HOME", alice.home.path().display())],
+        )
+        .home(
+            "bob",
+            working.join("bob").join("heartwood"),
+            [("RAD_HOME", bob.home.path().display())],
+        )
+        .home(
+            "eve",
+            working.join("eve").join("heartwood"),
+            [("RAD_HOME", eve.home.path().display())],
+        )
+        .run()
+        .unwrap();
+}
+
 #[test]
 fn rad_push_and_pull_patches() {
     let mut environment = Environment::new();