class Vec3 { public constructor ( public x = 0 , public y = 0 , public z = 0 ) { } } describe ( "a set of snapshots" , ( ) => { test ( "some snapshots" , ( ) => { expect ( 1 ) . toMatchSnapshot ( "an integer" ) ; expect ( 3.14 ) . toMatchSnapshot ( "a float" ) ; expect ( [ 1 , 2 , 3 , 4 , 5 ] ) . toMatchSnapshot ( "an integer array" ) ; let a = new Float64Array ( 4 ) ; a [ 0 ] = 1 ; a [ 1 ] = 2 ; a [ 2 ] = 3 ; a [ 3 ] = 4 ; expect ( a ) . toMatchSnapshot ( "a typed array" ) ; expect ( "a string" ) . toMatchSnapshot ( "a string" ) ; expect ( new Vec3 ( 1 , 2 , 3 ) ) . toMatchSnapshot ( "a reference" ) ; } ) ; } ) ;