" Test for lambda and closure func Test_lambda_feature() call assert_equal(1, has('lambda')) endfunc func Test_lambda_with_filter() let s:x = 2 call assert_equal([2, 3], filter([1, 2, 3], {i, v -> v >= s:x})) endfunc func Test_lambda_with_map() let s:x = 1 call assert_equal([2, 3, 4], map([1, 2, 3], {i, v -> v + s:x})) endfunc func Test_lambda_with_sort() call assert_equal([1, 2, 3, 4, 7], sort([3,7,2,1,4], {a, b -> a - b})) endfunc func Test_lambda_with_timer() if !has('timers') return endif let s:n = 0 let s:timer_id = 0 func! s:Foo() let s:timer_id = timer_start(10, {-> execute("let s:n += 1 | echo s:n", "")}, {"repeat": -1}) endfunc call s:Foo() " check timer works for i in range(0, 10) if s:n > 0 break endif sleep 10m endfor " do not collect lambda call test_garbagecollect_now() " check timer still works let m = s:n for i in range(0, 10) if s:n > m break endif sleep 10m endfor call timer_stop(s:timer_id) call assert_true(s:n > m) endfunc func Test_lambda_with_partial() let l:Cb = function({... -> ['zero', a:1, a:2, a:3]}, ['one', 'two']) call assert_equal(['zero', 'one', 'two', 'three'], l:Cb('three')) endfunc function Test_lambda_fails() call assert_equal(3, {a, b -> a + b}(1, 2)) call assert_fails('echo {a, a -> a + a}(1, 2)', 'E853:') call assert_fails('echo {a, b -> a + b)}(1, 2)', 'E15:') endfunc func Test_not_lamda() let x = {'>' : 'foo'} call assert_equal('foo', x['>']) endfunc func Test_lambda_capture_by_reference() let v = 1 let l:F = {x -> x + v} let v = 2 call assert_equal(12, l:F(10)) endfunc func Test_lambda_side_effect() func! s:update_and_return(arr) let a:arr[1] = 5 return a:arr endfunc func! s:foo(arr) return {-> s:update_and_return(a:arr)} endfunc let arr = [3,2,1] call assert_equal([3, 5, 1], s:foo(arr)()) endfunc func Test_lambda_refer_local_variable_from_other_scope() func! s:foo(X) return a:X() " refer l:x in s:bar() endfunc func! s:bar() let x = 123 return s:foo({-> x}) endfunc call assert_equal(123, s:bar()) endfunc func Test_lambda_do_not_share_local_variable() func! s:define_funcs() let l:One = {-> split(execute("let a = 'abc' | echo a"))[0]} let l:Two = {-> exists("a") ? a : "no"} return [l:One, l:Two] endfunc let l:F = s:define_funcs() call assert_equal('no', l:F[1]()) call assert_equal('abc', l:F[0]()) call assert_equal('no', l:F[1]()) endfunc func Test_lambda_closure_counter() func! s:foo() let x = 0 return {-> [execute("let x += 1"), x][-1]} endfunc let l:F = s:foo() call test_garbagecollect_now() call assert_equal(1, l:F()) call assert_equal(2, l:F()) call assert_equal(3, l:F()) call assert_equal(4, l:F()) endfunc func Test_lambda_with_a_var() func! s:foo() let x = 2 return {... -> a:000 + [x]} endfunc func! s:bar() return s:foo()(1) endfunc call assert_equal([1, 2], s:bar()) endfunc func Test_lambda_call_lambda_from_lambda() func! s:foo(x) let l:F1 = {-> {-> a:x}} return {-> l:F1()} endfunc let l:F = s:foo(1) call assert_equal(1, l:F()()) endfunc func Test_lambda_delfunc() func! s:gen() let pl = l: let l:Foo = {-> get(pl, "Foo", get(pl, "Bar", {-> 0}))} let l:Bar = l:Foo delfunction l:Foo return l:Bar endfunc let l:F = s:gen() call assert_fails(':call l:F()', 'E933:') endfunc func Test_lambda_scope() func! s:NewCounter() let c = 0 return {-> [execute('let c += 1'), c][-1]} endfunc func! s:NewCounter2() return {-> [execute('let c += 100'), c][-1]} endfunc let l:C = s:NewCounter() let l:D = s:NewCounter2() call assert_equal(1, l:C()) call assert_fails(':call l:D()', 'E121:') call assert_equal(2, l:C()) endfunc func Test_lambda_share_scope() func! s:New() let c = 0 let l:Inc0 = {-> [execute('let c += 1'), c][-1]} let l:Dec0 = {-> [execute('let c -= 1'), c][-1]} return [l:Inc0, l:Dec0] endfunc let [l:Inc, l:Dec] = s:New() call assert_equal(1, l:Inc()) call assert_equal(2, l:Inc()) call assert_equal(1, l:Dec()) endfunc func Test_lambda_circular_reference() func! s:Foo() let d = {} let d.f = {-> d} return d.f endfunc call s:Foo() call test_garbagecollect_now() let i = 0 | while i < 10000 | call s:Foo() | let i+= 1 | endwhile call test_garbagecollect_now() endfunc func Test_lambda_combination() call assert_equal(2, {x -> {x -> x}}(1)(2)) call assert_equal(10, {y -> {x -> x(y)(10)}({y -> y})}({z -> z})) call assert_equal(5.0, {x -> {y -> x / y}}(10)(2.0)) call assert_equal(6, {x -> {y -> {z -> x + y + z}}}(1)(2)(3)) call assert_equal(6, {x -> {f -> f(x)}}(3)({x -> x * 2})) call assert_equal(6, {f -> {x -> f(x)}}({x -> x * 2})(3)) " Z combinator let Z = {f -> {x -> f({y -> x(x)(y)})}({x -> f({y -> x(x)(y)})})} let Fact = {f -> {x -> x == 0 ? 1 : x * f(x - 1)}} call assert_equal(120, Z(Fact)(5)) endfunc func Test_closure_counter() func! s:foo() let x = 0 func! s:bar() closure let x += 1 return x endfunc return function('s:bar') endfunc let l:F = s:foo() call test_garbagecollect_now() call assert_equal(1, l:F()) call assert_equal(2, l:F()) call assert_equal(3, l:F()) call assert_equal(4, l:F()) endfunc func Test_closure_unlet() func! s:foo() let x = 1 func! s:bar() closure unlet x endfunc call s:bar() return l: endfunc call assert_false(has_key(s:foo(), 'x')) call test_garbagecollect_now() endfunc func LambdaFoo() let x = 0 func! LambdaBar() closure let x += 1 return x endfunc return function('LambdaBar') endfunc func Test_closure_refcount() let g:Count = LambdaFoo() call test_garbagecollect_now() call assert_equal(1, g:Count()) let g:Count2 = LambdaFoo() call test_garbagecollect_now() call assert_equal(1, g:Count2()) call assert_equal(2, g:Count()) call assert_equal(3, g:Count2()) delfunc LambdaFoo delfunc LambdaBar endfunc func Test_named_function_closure() func! Afoo() let x = 14 func! s:Abar() closure return x endfunc call assert_equal(14, s:Abar()) endfunc call Afoo() call assert_equal(14, s:Abar()) call test_garbagecollect_now() call assert_equal(14, s:Abar()) endfunc func Test_lambda_with_index() let List = {x -> [x]} let Extract = {-> function(List, ['foobar'])()[0]} call assert_equal('foobar', Extract()) endfunc