all: comply with linter recommendations #2

HTTP request now implicitly create request with context.

Any false positive related to not closing HTTP response body has been
annotated with "nolint:bodyclose".

In the example code, use consistent "// Output:" comment format, by
prefixing with single space.
Any comment on code now also prefixing with single space.

An error returned without variables now use [errors.New] instead of
[fmt.Errorf].
Any error returned using [fmt.Errorf] now wrapped using "%w" instead of
"%s".
Also, replace error checking using [errors.Is] or [errors.As], instead
of using equal/not-equal operator.

Any statement like "x = x OP y" now replaced with "x OP= y".
Also, swap statement is simplified using "x, y = y, x".
Any switch statement with single case now replaced with if-condition.

Any call to defer on function or program that call [os.Exit], now
replaced by calling the deferred function directly.

Any if-else condition now replaced with switch statement, if possible.

1 files changed, 11 insertions, 6 deletions

diff --git a/lib/sql/client.go b/lib/sql/client.go
index c281dab8..344ed76b 100644
--- a/lib/sql/client.go
+++ b/lib/sql/client.go
@@ -49,6 +49,7 @@ func NewClient(opts ClientOptions) (cl *Client, err error) {
 // FetchTableNames return the table names in current database schema sorted
 // in ascending order.
 func (cl *Client) FetchTableNames() (tableNames []string, err error) {
+	var logp = `FetchTableNames`
 	var q, v string
 
 	switch cl.DriverName {
@@ -63,27 +64,31 @@ func (cl *Client) FetchTableNames() (tableNames []string, err error) {
 		`
 	}
 
-	rows, err := cl.DB.Query(q)
+	var rows *sql.Rows
+
+	rows, err = cl.DB.Query(q)
 	if err != nil {
-		return nil, fmt.Errorf("FetchTableNames: " + err.Error())
+		return nil, fmt.Errorf(`%s: %w`, logp, err)
 	}
 
 	if len(cl.TableNames) > 0 {
 		cl.TableNames = cl.TableNames[:0]
 	}
+	defer func() {
+		_ = rows.Close()
+	}()
 
 	for rows.Next() {
 		err = rows.Scan(&v)
 		if err != nil {
-			_ = rows.Close()
-			return cl.TableNames, err
+			return cl.TableNames, fmt.Errorf(`%s: %w`, logp, err)
 		}
 
 		cl.TableNames = append(cl.TableNames, v)
 	}
 	err = rows.Err()
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf(`%s: %w`, logp, err)
 	}
 
 	return cl.TableNames, nil
@@ -313,7 +318,7 @@ func (cl *Client) TruncateTable(tableName string) (err error) {
 
 	_, err = cl.DB.Exec(q)
 	if err != nil {
-		return fmt.Errorf("TruncateTable %q: %s", tableName, err)
+		return fmt.Errorf(`TruncateTable %q: %w`, tableName, err)
 	}
 	return nil
 }