<s>
Jest	B-Language
is	O
a	O
JavaScript	B-Language
testing	O
framework	O
built	O
on	O
top	O
of	O
Jasmine	B-Language
and	O
maintained	O
by	O
Meta	O
(	O
formerly	O
Facebook	O
)	O
.	O
</s>
<s>
It	O
was	O
designed	O
and	O
built	O
by	O
Christoph	O
Nakazawa	O
with	O
a	O
focus	O
on	O
simplicity	O
and	O
support	O
for	O
large	O
web	B-Application
applications	I-Application
.	O
</s>
<s>
It	O
works	O
with	O
projects	O
using	O
Babel	B-Language
,	O
TypeScript	B-Language
,	O
Node.js	B-Language
,	O
React	B-Application
,	O
Angular	B-Language
,	O
Vue.js	B-Language
and	O
Svelte	B-Language
.	O
</s>
<s>
Jest	B-Language
does	O
n't	O
require	O
a	O
lot	O
of	O
configuration	O
for	O
first-time	O
users	O
of	O
a	O
testing	O
framework	O
.	O
</s>
<s>
Use	O
the	O
JavaScript	B-Language
package	O
manager	O
npm	B-Language
to	O
install	O
Jest	B-Language
in	O
Node.js	B-Language
:	O
</s>
<s>
Our	O
test	O
case	O
will	O
be	O
in	O
a	O
file	O
named	O
sum.test.js	O
for	O
Jest	B-Language
to	O
automatically	O
pick	O
it	O
up	O
as	O
a	O
test	O
case	O
for	O
sum.js	O
.	O
</s>
