Unit test DB showing RESTART doesn't alter WAL

db/db_checkpoint_test.go

@@ -0,0 +1,117 @@
+package db
+
+import (
+	"bytes"
+	"os"
+	"testing"
+)
+
+// Test_WALDatabaseCheckpointOKNoWAL tests that a checkpoint succeeds
+// even when no WAL file exists.
+func Test_WALDatabaseCheckpointOKNoWAL(t *testing.T) {
+	path := mustTempFile()
+	defer os.Remove(path)
+
+	db, err := Open(path, false, true)
+	if err != nil {
+		t.Fatalf("failed to open database in WAL mode: %s", err.Error())
+	}
+	if !db.WALEnabled() {
+		t.Fatalf("WAL mode not enabled")
+	}
+	if fileExists(db.WALPath()) {
+		t.Fatalf("WAL file exists when no writes have happened")
+	}
+	defer db.Close()
+	if err := db.Checkpoint(CheckpointTruncate); err != nil {
+		t.Fatalf("failed to checkpoint database in WAL mode with non-existent WAL: %s", err.Error())
+	}
+}
+
+// Test_WALDatabaseCheckpointOKDelete tests that a checkpoint returns no error
+// even when the database is opened in DELETE mode.
+func Test_WALDatabaseCheckpointOKDelete(t *testing.T) {
+	path := mustTempFile()
+	defer os.Remove(path)
+
+	db, err := Open(path, false, false)
+	if err != nil {
+		t.Fatalf("failed to open database in DELETE mode: %s", err.Error())
+	}
+	if db.WALEnabled() {
+		t.Fatalf("WAL mode enabled")
+	}
+	defer db.Close()
+	if err := db.Checkpoint(CheckpointTruncate); err != nil {
+		t.Fatalf("failed to checkpoint database in DELETE mode: %s", err.Error())
+	}
+}
+
+// Test_WALDatabaseCheckpoint_Restart tests that a checkpoint restart
+// returns no error and that the WAL file is not modified even though
+// all the WAL pages are copied to the database file. Then Truncate
+// is called and the WAL file is deleted.
+func Test_WALDatabaseCheckpoint_RestartTruncate(t *testing.T) {
+	path := mustTempFile()
+	defer os.Remove(path)
+	db, err := Open(path, false, true)
+	if err != nil {
+		t.Fatalf("failed to open database in DELETE mode: %s", err.Error())
+	}
+
+	_, err = db.ExecuteStringStmt(`CREATE TABLE foo (id INTEGER NOT NULL PRIMARY KEY, name TEXT)`)
+	if err != nil {
+		t.Fatalf("failed to execute on single node: %s", err.Error())
+	}
+	for i := 0; i < 100; i++ {
+		_, err := db.ExecuteStringStmt(`INSERT INTO foo(name) VALUES("fiona")`)
+		if err != nil {
+			t.Fatalf("failed to execute INSERT on single node: %s", err.Error())
+		}
+	}
+
+	walPreBytes, err := os.ReadFile(db.WALPath())
+	if err != nil {
+		t.Fatalf("failed to read wal file: %s", err.Error())
+	}
+	if err := db.Checkpoint(CheckpointRestart); err != nil {
+		t.Fatalf("failed to checkpoint database in DELETE mode: %s", err.Error())
+	}
+	walPostBytes, err := os.ReadFile(db.WALPath())
+	if err != nil {
+		t.Fatalf("failed to read wal file: %s", err.Error())
+	}
+	if !bytes.Equal(walPreBytes, walPostBytes) {
+		t.Fatalf("wal files should be identical after checkpoint restart")
+	}
+
+	// query the data to make sure all is well.
+	rows, err := db.QueryStringStmt(`SELECT COUNT(*) FROM foo`)
+	if err != nil {
+		t.Fatalf("failed to execute query on single node: %s", err.Error())
+	}
+	if exp, got := `[{"columns":["COUNT(*)"],"types":["integer"],"values":[[100]]}]`, asJSON(rows); exp != got {
+		t.Fatalf("expected %s, got %s", exp, got)
+	}
+
+	if err := db.Checkpoint(CheckpointTruncate); err != nil {
+		t.Fatalf("failed to checkpoint database in DELETE mode: %s", err.Error())
+	}
+	sz, err := fileSize(db.WALPath())
+	if err != nil {
+		t.Fatalf("wal file should be deleted after checkpoint truncate")
+	}
+	if sz != 0 {
+		t.Fatalf("wal file should be zero length after checkpoint truncate")
+	}
+
+	// query the data to make sure all is still well.
+	rows, err = db.QueryStringStmt(`SELECT COUNT(*) FROM foo`)
+	if err != nil {
+		t.Fatalf("failed to execute query on single node: %s", err.Error())
+	}
+	if exp, got := `[{"columns":["COUNT(*)"],"types":["integer"],"values":[[100]]}]`, asJSON(rows); exp != got {
+		t.Fatalf("expected %s, got %s", exp, got)
+	}
+
+}

db/db_test.go

@@ -681,47 +681,6 @@ func Test_WALDatabaseCreatedOK(t *testing.T) {
 	}
 }
 
-// Test_WALDatabaseCheckpointOKNoWAL tests that a checkpoint succeeds
-// even when no WAL file exists.
-func Test_WALDatabaseCheckpointOKNoWAL(t *testing.T) {
-	path := mustTempFile()
-	defer os.Remove(path)
-
-	db, err := Open(path, false, true)
-	if err != nil {
-		t.Fatalf("failed to open database in WAL mode: %s", err.Error())
-	}
-	if !db.WALEnabled() {
-		t.Fatalf("WAL mode not enabled")
-	}
-	if fileExists(db.WALPath()) {
-		t.Fatalf("WAL file exists when no writes have happened")
-	}
-	defer db.Close()
-	if err := db.Checkpoint(CheckpointTruncate); err != nil {
-		t.Fatalf("failed to checkpoint database in WAL mode with non-existent WAL: %s", err.Error())
-	}
-}
-
-// Test_WALDatabaseCheckpointOKDelete tests that a checkpoint returns no error
-// even when the database is opened in DELETE mode.
-func Test_WALDatabaseCheckpointOKDelete(t *testing.T) {
-	path := mustTempFile()
-	defer os.Remove(path)
-
-	db, err := Open(path, false, false)
-	if err != nil {
-		t.Fatalf("failed to open database in DELETE mode: %s", err.Error())
-	}
-	if db.WALEnabled() {
-		t.Fatalf("WAL mode enabled")
-	}
-	defer db.Close()
-	if err := db.Checkpoint(CheckpointTruncate); err != nil {
-		t.Fatalf("failed to checkpoint database in DELETE mode: %s", err.Error())
-	}
-}
-
 // Test_WALDatabaseCreatedOKFromDELETE tests that a WAL database is created properly,
 // even when supplied with a DELETE-mode database.
 func Test_WALDatabaseCreatedOKFromDELETE(t *testing.T) {