raft: generate MsgApp in TestHandleMsgApp

Epic: none
Release note: none

Author: pav-kv

pkg/raft/log_test.go

@@ -999,27 +999,30 @@ func (i index) terms(terms ...uint64) []pb.Entry {
 	return entries
 }
 
-// append generates a valid LeadSlice of entries appended after the given entry
-// ID, at indices [id.index+1, id.index+len(terms)], with the given terms of
-// each entry. Terms must be >= id.term, and non-decreasing.
-func (id entryID) append(terms ...uint64) LeadSlice {
-	term := id.term
-	if ln := len(terms); ln != 0 {
-		term = terms[ln-1]
-	}
-	ls := LeadSlice{
-		term: term,
-		LogSlice: LogSlice{
-			prev:    id,
-			entries: index(id.index + 1).terms(terms...),
-		},
+// terms generates a LogSlice of entries with the given terms appended after the
+// given entry ID.
+func (id entryID) terms(terms ...uint64) LogSlice {
+	ls := LogSlice{
+		prev:    id,
+		entries: index(id.index + 1).terms(terms...),
 	}
 	if err := ls.valid(); err != nil {
 		panic(err)
 	}
 	return ls
 }
 
+// append generates a valid LeadSlice of entries appended after the given entry
+// ID, at indices [id.index+1, id.index+len(terms)], with the given terms of
+// each entry. Terms must be >= id.term, and non-decreasing.
+func (id entryID) append(terms ...uint64) LeadSlice {
+	ls := id.terms(terms...)
+	return LeadSlice{
+		term:     ls.lastEntryID().term,
+		LogSlice: ls,
+	}
+}
+
 // intRange returns a slice containing integers in [from, to) interval.
 func intRange[T constraints.Integer](from, to T) []T {
 	slice := make([]T, to-from)

pkg/raft/raft_test.go

@@ -1375,42 +1375,52 @@ func TestStepIgnoreOldTermMsg(t *testing.T) {
 //     delete the existing entry and all that follow it; append any new entries not already in the log.
 //  3. If leaderCommit > commitIndex, set commitIndex = min(leaderCommit, index of last new entry).
 func TestHandleMsgApp(t *testing.T) {
-	tests := []struct {
+	const term = 2
+	init := index(1).terms(1, 2) // the initial log
+
+	msgApp := func(term uint64, ls LogSlice, commit uint64) pb.Message {
+		return pb.Message{
+			From: 2, To: 1, Type: pb.MsgApp, Term: term,
+			Index: ls.prev.index, LogTerm: ls.prev.term, Entries: ls.Entries(),
+			Commit: commit,
+		}
+	}
+	for _, tt := range []struct {
 		m       pb.Message
 		wIndex  uint64
 		wCommit uint64
 		wReject bool
 	}{
 		// Ensure 1
-		{pb.Message{Type: pb.MsgApp, Term: 3, LogTerm: 3, Index: 2, Commit: 3}, 2, 0, true}, // previous log mismatch
-		{pb.Message{Type: pb.MsgApp, Term: 3, LogTerm: 3, Index: 3, Commit: 3}, 2, 0, true}, // previous log non-exist
+		{m: msgApp(3, entryID{index: 2, term: 3}.terms(), 3), wIndex: 2, wReject: true}, // previous log mismatch
+		{m: msgApp(3, entryID{index: 3, term: 3}.terms(), 3), wIndex: 2, wReject: true}, // previous log non-exist
 
 		// Ensure 2
-		{pb.Message{Type: pb.MsgApp, Term: 2, LogTerm: 1, Index: 1, Commit: 1}, 2, 1, false},
-		{pb.Message{Type: pb.MsgApp, Term: 3, LogTerm: 0, Index: 0, Commit: 1, Entries: []pb.Entry{{Index: 1, Term: 3}}}, 1, 1, false},
-		{pb.Message{Type: pb.MsgApp, Term: 2, LogTerm: 2, Index: 2, Commit: 3, Entries: []pb.Entry{{Index: 3, Term: 2}, {Index: 4, Term: 2}}}, 4, 3, false},
-		{pb.Message{Type: pb.MsgApp, Term: 2, LogTerm: 2, Index: 2, Commit: 4, Entries: []pb.Entry{{Index: 3, Term: 2}}}, 3, 3, false},
-		{pb.Message{Type: pb.MsgApp, Term: 2, LogTerm: 1, Index: 1, Commit: 4, Entries: []pb.Entry{{Index: 2, Term: 2}}}, 2, 2, false},
+		{m: msgApp(2, entryID{index: 1, term: 1}.terms(), 1), wIndex: 2, wCommit: 1},
+		{m: msgApp(3, entryID{}.terms(3), 1), wIndex: 1, wCommit: 1},
+		{m: msgApp(2, entryID{index: 2, term: 2}.terms(2, 2), 3), wIndex: 4, wCommit: 3},
+		{m: msgApp(2, entryID{index: 2, term: 2}.terms(2), 3), wIndex: 3, wCommit: 3},
+		{m: msgApp(2, entryID{index: 1, term: 1}.terms(2), 4), wIndex: 2, wCommit: 2},
 
 		// Ensure 3
-		{pb.Message{Type: pb.MsgApp, Term: 1, LogTerm: 1, Index: 1, Commit: 3}, 2, 1, false},                                           // match entry 1, commit up to last new entry 1
-		{pb.Message{Type: pb.MsgApp, Term: 2, LogTerm: 1, Index: 1, Commit: 3, Entries: []pb.Entry{{Index: 2, Term: 2}}}, 2, 2, false}, // match entry 1, commit up to last new entry 2
-		{pb.Message{Type: pb.MsgApp, Term: 2, LogTerm: 2, Index: 2, Commit: 3}, 2, 2, false},                                           // match entry 2, commit up to last new entry 2
-		{pb.Message{Type: pb.MsgApp, Term: 2, LogTerm: 2, Index: 2, Commit: 4}, 2, 2, false},                                           // commit up to log.last()
-	}
-
-	for i, tt := range tests {
-		storage := newTestMemoryStorage(withPeers(1))
-		require.NoError(t, storage.Append(index(1).terms(1, 2)))
-		sm := newTestRaft(1, 10, 1, storage)
-		sm.becomeFollower(2, None)
-
-		sm.handleAppendEntries(tt.m)
-		assert.Equal(t, tt.wIndex, sm.raftLog.lastIndex(), "#%d", i)
-		assert.Equal(t, tt.wCommit, sm.raftLog.committed, "#%d", i)
-		m := sm.readMessages()
-		require.Len(t, m, 1, "#%d", i)
-		assert.Equal(t, tt.wReject, m[0].Reject, "#%d", i)
+		{m: msgApp(1, entryID{index: 1, term: 1}.terms(), 3), wIndex: 2, wCommit: 1},  // match entry 1, commit up to last new entry 1
+		{m: msgApp(2, entryID{index: 1, term: 1}.terms(2), 3), wIndex: 2, wCommit: 2}, // match entry 1, commit up to last new entry 2
+		{m: msgApp(2, entryID{index: 2, term: 2}.terms(), 3), wIndex: 2, wCommit: 2},  // match entry 2, commit up to last new entry 2
+		{m: msgApp(2, entryID{index: 2, term: 2}.terms(), 4), wIndex: 2, wCommit: 2},  // commit up to log.last()
+	} {
+		t.Run("", func(t *testing.T) {
+			storage := newTestMemoryStorage(withPeers(1, 2))
+			require.NoError(t, storage.Append(init))
+			sm := newTestRaft(1, 10, 1, storage)
+			sm.becomeFollower(term, None)
+
+			sm.handleAppendEntries(tt.m)
+			assert.Equal(t, tt.wIndex, sm.raftLog.lastIndex())
+			assert.Equal(t, tt.wCommit, sm.raftLog.committed)
+			m := sm.readMessages()
+			require.Len(t, m, 1)
+			assert.Equal(t, tt.wReject, m[0].Reject)
+		})
 	}
 }