fix: improve fuzzing coverage for jsn package

internal/serv/cmd_seed.go

@@ -18,6 +18,7 @@ import (
 	"github.com/dosco/super-graph/core"
 	"github.com/gosimple/slug"
 	"github.com/jackc/pgx/v4"
+	"github.com/jackc/pgx/v4/stdlib"
 	"github.com/spf13/cobra"
 )
 
@@ -200,12 +201,12 @@ func importCSV(table, filename string) int64 {
 		cols = append(cols, c.(string))
 	}
 
-	conn, err := acquireConn(db)
+	conn, err := stdlib.AcquireConn(db)
 	if err != nil {
 		log.Fatalf("ERR %v", err)
 	}
 	//nolint: errcheck
-	defer releaseConn(db, conn)
+	defer stdlib.ReleaseConn(db, conn)
 
 	n, err := conn.CopyFrom(
 		context.Background(),

internal/serv/stdlib.go

@@ -1,67 +0,0 @@
-package serv
-
-import (
-	"context"
-	"database/sql"
-	"sync"
-	"time"
-
-	errors "golang.org/x/xerrors"
-
-	"github.com/jackc/pgx/v4"
-)
-
-type ctxKey int
-
-var ctxKeyFakeTx ctxKey = 0
-
-var errNotPgx = errors.New("not pgx *sql.DB")
-
-var (
-	fakeTxMutex sync.Mutex
-	fakeTxConns map[*pgx.Conn]*sql.Tx
-)
-
-func acquireConn(db *sql.DB) (*pgx.Conn, error) {
-	var conn *pgx.Conn
-	ctx := context.WithValue(context.Background(), ctxKeyFakeTx, &conn)
-	tx, err := db.BeginTx(ctx, nil)
-	if err != nil {
-		return nil, err
-	}
-	if conn == nil {
-		if err := tx.Rollback(); err != nil {
-			return nil, err
-		}
-		return nil, errNotPgx
-	}
-
-	fakeTxMutex.Lock()
-	fakeTxConns[conn] = tx
-	fakeTxMutex.Unlock()
-
-	return conn, nil
-}
-
-func releaseConn(db *sql.DB, conn *pgx.Conn) error {
-	var tx *sql.Tx
-	var ok bool
-
-	if conn.PgConn().IsBusy() || conn.PgConn().TxStatus() != 'I' {
-		ctx, cancel := context.WithTimeout(context.Background(), time.Second)
-		defer cancel()
-		conn.Close(ctx)
-	}
-
-	fakeTxMutex.Lock()
-	tx, ok = fakeTxConns[conn]
-	if ok {
-		delete(fakeTxConns, conn)
-		fakeTxMutex.Unlock()
-	} else {
-		fakeTxMutex.Unlock()
-		return errors.Errorf("can't release conn that is not acquired")
-	}
-
-	return tx.Rollback()
-}