Re: [Tarantool-patches] [PATCH v1 03/21] sql: refactor HEX() function

[Mergen Imeev via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

Thank you for the review! My answer and diff below. Also, I added a description
of the function.

On Fri, Oct 15, 2021 at 12:43:14AM +0200, Vladislav Shpilevoy wrote:
> Good job on the patch!
> 
> > diff --git a/src/box/sql/func.c b/src/box/sql/func.c
> > index 7886f5f40..e5d763be1 100644
> > --- a/src/box/sql/func.c
> > +++ b/src/box/sql/func.c
> > @@ -800,6 +800,39 @@ func_greatest_least(struct sql_context *ctx, int argc, struct Mem *argv)
> >  		ctx->is_aborted = true;
> >  }
> >  
> > +/** Implementation of the HEX() function. */
> > +static const char hexdigits[] = {
> > +	'0', '1', '2', '3', '4', '5', '6', '7',
> > +	'8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
> > +};
> > +
> > +static void
> > +func_hex(struct sql_context *ctx, int argc, struct Mem *argv)
> > +{
> > +	assert(argc == 1);
> > +	(void)argc;
> > +	struct Mem *arg = &argv[0];
> > +	if (mem_is_null(arg))
> > +		return mem_set_null(ctx->pOut);
> 
> Isn't pOut already null? I thought it is created as null.
True, fixed.


Diff:

diff --git a/src/box/sql/func.c b/src/box/sql/func.c
index 96525ed3a..2abf6811d 100644
--- a/src/box/sql/func.c
+++ b/src/box/sql/func.c
@@ -796,7 +796,11 @@ func_greatest_least(struct sql_context *ctx, int argc, struct Mem *argv)
 		ctx->is_aborted = true;
 }
 
-/** Implementation of the HEX() function. */
+/**
+ * Implementation of the HEX() function.
+ *
+ * The HEX() function returns the hexadecimal representation of the argument.
+ */
 static const char hexdigits[] = {
 	'0', '1', '2', '3', '4', '5', '6', '7',
 	'8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
@@ -809,7 +813,7 @@ func_hex(struct sql_context *ctx, int argc, struct Mem *argv)
 	(void)argc;
 	struct Mem *arg = &argv[0];
 	if (mem_is_null(arg))
-		return mem_set_null(ctx->pOut);
+		return;
 
 	assert(mem_is_bin(arg) && arg->n >= 0);
 	if (arg->n == 0)