Buffer of a Linestring returns a Polygon with hole artifact

[nbvfgh]

Considering following queries:

DROP TABLE IF EXISTS t1;
DROP TABLE IF EXISTS t2;

CREATE TABLE t1 (geom geometry);
CREATE TABLE t2 (geom geometry);

INSERT INTO t1 VALUES (ST_GeomFromText('LINESTRING (1.6 0.7, 0.7 4.7, 145.6 137.7, 146.3 137.1, 146.3 137, 146.6 136.7)', 0));
INSERT INTO t2 VALUES (ST_Buffer(ST_GeomFromText('LINESTRING (1.6 0.7, 0.7 4.7, 145.6 137.7, 146.3 137.1, 146.3 137, 146.6 136.7)', 0)
,13));

SELECT ST_Distance(t1.geom,ST_ExteriorRing(t2.geom)), ST_Distance(t1.geom, ST_InteriorRingN(t2.geom, 1)) FROM t1, t2;
--result: {12.92237619733858, 0.12670001936357617}

SELECT ST_AsText(ST_InteriorRingN(geom, 1)) FROM t2;
--result: {LINESTRING(136.30661486829771 128.78362948415392,136.19999999999973 128.90000000000035,137.10761184457445 127.80761184457532,136.30661486829771 128.78362948415392)}

The buffer has created an unexpected hole and is too close to the original input.

[dr-jts]

This is a bug in buffer topology building.