This is a testharness.js-based test.
Found 90 tests; 73 PASS, 17 FAIL, 0 TIMEOUT, 0 NOTRUN.
PASS URLSearchParams constructed with: test 
PASS request.formData() with input: test 
PASS response.formData() with input: test 
PASS URLSearchParams constructed with: ﻿test=﻿ 
FAIL request.formData() with input: ﻿test=﻿ assert_array_equals: property 0, expected "﻿test" but got "test"
FAIL response.formData() with input: ﻿test=﻿ assert_array_equals: property 0, expected "﻿test" but got "test"
PASS URLSearchParams constructed with: %EF%BB%BFtest=%EF%BB%BF 
PASS request.formData() with input: %EF%BB%BFtest=%EF%BB%BF 
PASS response.formData() with input: %EF%BB%BFtest=%EF%BB%BF 
FAIL URLSearchParams constructed with: %FE%FF assert_array_equals: property 0, expected "\ufffd\ufffd" but got "þÿ"
FAIL request.formData() with input: %FE%FF assert_array_equals: property 0, expected "\ufffd\ufffd" but got "þÿ"
FAIL response.formData() with input: %FE%FF assert_array_equals: property 0, expected "\ufffd\ufffd" but got "þÿ"
FAIL URLSearchParams constructed with: %FF%FE assert_array_equals: property 0, expected "\ufffd\ufffd" but got "ÿþ"
FAIL request.formData() with input: %FF%FE assert_array_equals: property 0, expected "\ufffd\ufffd" but got "ÿþ"
FAIL response.formData() with input: %FF%FE assert_array_equals: property 0, expected "\ufffd\ufffd" but got "ÿþ"
PASS URLSearchParams constructed with: †&†=x 
PASS request.formData() with input: †&†=x 
PASS response.formData() with input: †&†=x 
FAIL URLSearchParams constructed with: %C2 assert_array_equals: property 0, expected "\ufffd" but got "Â"
FAIL request.formData() with input: %C2 assert_array_equals: property 0, expected "\ufffd" but got "Â"
FAIL response.formData() with input: %C2 assert_array_equals: property 0, expected "\ufffd" but got "Â"
FAIL URLSearchParams constructed with: %C2x assert_array_equals: property 0, expected "\ufffdx" but got "Âx"
FAIL request.formData() with input: %C2x assert_array_equals: property 0, expected "\ufffdx" but got "Âx"
FAIL response.formData() with input: %C2x assert_array_equals: property 0, expected "\ufffdx" but got "Âx"
FAIL URLSearchParams constructed with: _charset_=windows-1252&test=%C2x assert_array_equals: property 1, expected "\ufffdx" but got "Âx"
FAIL request.formData() with input: _charset_=windows-1252&test=%C2x assert_array_equals: property 1, expected "\ufffdx" but got "Âx"
FAIL response.formData() with input: _charset_=windows-1252&test=%C2x assert_array_equals: property 1, expected "\ufffdx" but got "Âx"
PASS URLSearchParams constructed with:  
PASS request.formData() with input:  
PASS response.formData() with input:  
PASS URLSearchParams constructed with: a 
PASS request.formData() with input: a 
PASS response.formData() with input: a 
PASS URLSearchParams constructed with: a=b 
PASS request.formData() with input: a=b 
PASS response.formData() with input: a=b 
PASS URLSearchParams constructed with: a= 
PASS request.formData() with input: a= 
PASS response.formData() with input: a= 
PASS URLSearchParams constructed with: =b 
PASS request.formData() with input: =b 
PASS response.formData() with input: =b 
PASS URLSearchParams constructed with: & 
PASS request.formData() with input: & 
PASS response.formData() with input: & 
PASS URLSearchParams constructed with: &a 
PASS request.formData() with input: &a 
PASS response.formData() with input: &a 
PASS URLSearchParams constructed with: a& 
PASS request.formData() with input: a& 
PASS response.formData() with input: a& 
PASS URLSearchParams constructed with: a&a 
PASS request.formData() with input: a&a 
PASS response.formData() with input: a&a 
PASS URLSearchParams constructed with: a&b&c 
PASS request.formData() with input: a&b&c 
PASS response.formData() with input: a&b&c 
PASS URLSearchParams constructed with: a=b&c=d 
PASS request.formData() with input: a=b&c=d 
PASS response.formData() with input: a=b&c=d 
PASS URLSearchParams constructed with: a=b&c=d& 
PASS request.formData() with input: a=b&c=d& 
PASS response.formData() with input: a=b&c=d& 
PASS URLSearchParams constructed with: &&&a=b&&&&c=d& 
PASS request.formData() with input: &&&a=b&&&&c=d& 
PASS response.formData() with input: &&&a=b&&&&c=d& 
PASS URLSearchParams constructed with: a=a&a=b&a=c 
PASS request.formData() with input: a=a&a=b&a=c 
PASS response.formData() with input: a=a&a=b&a=c 
PASS URLSearchParams constructed with: a==a 
PASS request.formData() with input: a==a 
PASS response.formData() with input: a==a 
PASS URLSearchParams constructed with: a=a+b+c+d 
PASS request.formData() with input: a=a+b+c+d 
PASS response.formData() with input: a=a+b+c+d 
PASS URLSearchParams constructed with: %=a 
PASS request.formData() with input: %=a 
PASS response.formData() with input: %=a 
PASS URLSearchParams constructed with: %a=a 
PASS request.formData() with input: %a=a 
PASS response.formData() with input: %a=a 
PASS URLSearchParams constructed with: %a_=a 
PASS request.formData() with input: %a_=a 
PASS response.formData() with input: %a_=a 
PASS URLSearchParams constructed with: %61=a 
PASS request.formData() with input: %61=a 
PASS response.formData() with input: %61=a 
PASS URLSearchParams constructed with: %61+%4d%4D= 
PASS request.formData() with input: %61+%4d%4D= 
PASS response.formData() with input: %61+%4d%4D= 
Harness: the test ran to completion.