# probe_and_replicate: a new leader probes a follower carrying a DIVERGENT, uncommitted log tail and
# overwrites the conflicting entry (Raft §5.3 truncation). Elect n1 and commit one command; isolate
# n1 and let it append an uncommitted entry "a" at index 3 that no one else sees; meanwhile {2,3}
# elect n2 at term 2, whose election no-op lands at index 3 (term 2) — so index 3 now DIVERGES
# (n1 has a@t1, the others have the no-op@t2). On recovery n1 adopts the higher term, rejects the
# conflicting append, and the leader probes back and overwrites n1's stale tail into agreement.
add-nodes 3 voters=(1,2,3)
----
n1: created voters={1,2,3} term=0 commit=0 last=0
n2: created voters={1,2,3} term=0 commit=0 last=0
n3: created voters={1,2,3} term=0 commit=0 last=0

campaign 1
----
n1 candidate term=1
RequestVote term=1 last=0/0 prevote=false
RequestVote term=1 last=0/0 prevote=false

stabilize
----
> n2 recv RequestVote term=1 last=0/0 prevote=false
> n3 recv RequestVote term=1 last=0/0 prevote=false
> n2 ready
  VoteResponse term=1 prevote=false reject=false
> n3 ready
  VoteResponse term=1 prevote=false reject=false
> n1 recv VoteResponse term=1 prevote=false reject=false
> n1 recv VoteResponse term=1 prevote=false reject=false
> n1 ready
  Heartbeat term=1 commit=0
  Heartbeat term=1 commit=0
  AppendEntries term=1 prev=0/0 commit=0 entries=[1/1 empty]
  AppendEntries term=1 prev=0/0 commit=0 entries=[1/1 empty]
  n1 leader-changed term=1 lead=1
> n2 recv Heartbeat term=1 commit=0
> n3 recv Heartbeat term=1 commit=0
> n2 recv AppendEntries term=1 prev=0/0 commit=0 entries=[1/1 empty]
> n3 recv AppendEntries term=1 prev=0/0 commit=0 entries=[1/1 empty]
> n2 ready
  HeartbeatResponse term=1
  AppendResponse term=1 match=1
  n2 leader-changed term=1 lead=1
> n3 ready
  HeartbeatResponse term=1
  AppendResponse term=1 match=1
  n3 leader-changed term=1 lead=1
> n1 recv HeartbeatResponse term=1
> n1 recv AppendResponse term=1 match=1
> n1 recv HeartbeatResponse term=1
> n1 recv AppendResponse term=1 match=1
> n1 ready
  AppendEntries term=1 prev=0/0 commit=0 entries=[1/1 empty]
  AppendEntries term=1 prev=1/1 commit=1 entries=[]
  AppendEntries term=1 prev=0/0 commit=1 entries=[1/1 empty]
  AppendEntries term=1 prev=1/1 commit=1 entries=[]
> n2 recv AppendEntries term=1 prev=0/0 commit=0 entries=[1/1 empty]
> n2 recv AppendEntries term=1 prev=1/1 commit=1 entries=[]
> n3 recv AppendEntries term=1 prev=0/0 commit=1 entries=[1/1 empty]
> n3 recv AppendEntries term=1 prev=1/1 commit=1 entries=[]
> n2 ready
  AppendResponse term=1 match=1
  AppendResponse term=1 match=1
> n3 ready
  AppendResponse term=1 match=1
  AppendResponse term=1 match=1
> n1 recv AppendResponse term=1 match=1
> n1 recv AppendResponse term=1 match=1
> n1 recv AppendResponse term=1 match=1
> n1 recv AppendResponse term=1 match=1

propose 1 x
----
AppendEntries term=1 prev=1/1 commit=1 entries=[1/2 normal 0x010000000000000078]
AppendEntries term=1 prev=1/1 commit=1 entries=[1/2 normal 0x010000000000000078]

stabilize
----
> n2 recv AppendEntries term=1 prev=1/1 commit=1 entries=[1/2 normal 0x010000000000000078]
> n3 recv AppendEntries term=1 prev=1/1 commit=1 entries=[1/2 normal 0x010000000000000078]
> n2 ready
  AppendResponse term=1 match=2
> n3 ready
  AppendResponse term=1 match=2
> n1 recv AppendResponse term=1 match=2
> n1 recv AppendResponse term=1 match=2
> n1 ready
  AppendEntries term=1 prev=1/2 commit=2 entries=[]
  AppendEntries term=1 prev=1/2 commit=2 entries=[]
  n1 applied index=2
> n2 recv AppendEntries term=1 prev=1/2 commit=2 entries=[]
> n3 recv AppendEntries term=1 prev=1/2 commit=2 entries=[]
> n2 ready
  AppendResponse term=1 match=2
  n2 applied index=2
> n3 ready
  AppendResponse term=1 match=2
  n3 applied index=2
> n1 recv AppendResponse term=1 match=2
> n1 recv AppendResponse term=1 match=2

isolate 1
----
n1 isolated

propose 1 a
----
ok

campaign 2
----
n2 candidate term=2
RequestVote term=2 last=1/2 prevote=false
n2 leader-changed term=2 lead=none

stabilize
----
> n3 recv RequestVote term=2 last=1/2 prevote=false
> n3 ready
  VoteResponse term=2 prevote=false reject=false
  n3 leader-changed term=2 lead=none
> n2 recv VoteResponse term=2 prevote=false reject=false
> n2 ready
  Heartbeat term=2 commit=0
  AppendEntries term=2 prev=1/2 commit=2 entries=[2/3 empty]
  n2 leader-changed term=2 lead=2
> n3 recv Heartbeat term=2 commit=0
> n3 recv AppendEntries term=2 prev=1/2 commit=2 entries=[2/3 empty]
> n3 ready
  HeartbeatResponse term=2
  AppendResponse term=2 match=3
  n3 leader-changed term=2 lead=2
> n2 recv HeartbeatResponse term=2
> n2 recv AppendResponse term=2 match=3
> n2 ready
  AppendEntries term=2 prev=1/2 commit=2 entries=[2/3 empty]
  AppendEntries term=2 prev=2/3 commit=3 entries=[]
> n3 recv AppendEntries term=2 prev=1/2 commit=2 entries=[2/3 empty]
> n3 recv AppendEntries term=2 prev=2/3 commit=3 entries=[]
> n3 ready
  AppendResponse term=2 match=3
  AppendResponse term=2 match=3
> n2 recv AppendResponse term=2 match=3
> n2 recv AppendResponse term=2 match=3

raft-log 1
----
n1: commit=2 applied=2 last=3
  1/1 empty
  1/2 normal 0x010000000000000078
  1/3 normal 0x010000000000000061

raft-log 2
----
n2: commit=3 applied=3 last=3
  1/1 empty
  1/2 normal 0x010000000000000078
  2/3 empty

recover 1
----
n1 recovered

tick-heartbeat 2
----
Heartbeat term=2 commit=0
Heartbeat term=2 commit=3

stabilize
----
> n1 recv Heartbeat term=2 commit=0
> n3 recv Heartbeat term=2 commit=3
> n1 ready
  HeartbeatResponse term=2
  n1 leader-changed term=2 lead=none
  n1 leader-changed term=2 lead=2
> n3 ready
  HeartbeatResponse term=2
> n2 recv HeartbeatResponse term=2
> n2 recv HeartbeatResponse term=2
> n2 ready
  AppendEntries term=2 prev=1/2 commit=3 entries=[2/3 empty]
  AppendEntries term=2 prev=2/3 commit=3 entries=[]
> n1 recv AppendEntries term=2 prev=1/2 commit=3 entries=[2/3 empty]
> n3 recv AppendEntries term=2 prev=2/3 commit=3 entries=[]
> n1 ready
  AppendResponse term=2 match=3
> n3 ready
  AppendResponse term=2 match=3
> n2 recv AppendResponse term=2 match=3
> n2 recv AppendResponse term=2 match=3
> n2 ready
  AppendEntries term=2 prev=2/3 commit=3 entries=[]
> n1 recv AppendEntries term=2 prev=2/3 commit=3 entries=[]
> n1 ready
  AppendResponse term=2 match=3
> n2 recv AppendResponse term=2 match=3

raft-log 1
----
n1: commit=3 applied=3 last=3
  1/1 empty
  1/2 normal 0x010000000000000078
  2/3 empty

