diff options
Diffstat (limited to 'test/closure.go')
-rw-r--r-- | test/closure.go | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/test/closure.go b/test/closure.go new file mode 100644 index 0000000..c4a3124 --- /dev/null +++ b/test/closure.go @@ -0,0 +1,128 @@ +// run + +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Test the behavior of closures. + +package main + +import "runtime" + +var c = make(chan int) + +func check(a []int) { + for i := 0; i < len(a); i++ { + n := <-c + if n != a[i] { + println("want", a[i], "got", n, "at", i) + panic("fail") + } + } +} + +func f() { + var i, j int + + i = 1 + j = 2 + f := func() { + c <- i + i = 4 + g := func() { + c <- i + c <- j + } + g() + c <- i + } + j = 5 + f() +} + +// Accumulator generator +func accum(n int) func(int) int { + return func(i int) int { + n += i + return n + } +} + +func g(a, b func(int) int) { + c <- a(2) + c <- b(3) + c <- a(4) + c <- b(5) +} + +func h() { + var x8 byte = 100 + var x64 int64 = 200 + + c <- int(x8) + c <- int(x64) + f := func(z int) { + g := func() { + c <- int(x8) + c <- int(x64) + c <- z + } + g() + c <- int(x8) + c <- int(x64) + c <- int(z) + } + x8 = 101 + x64 = 201 + f(500) +} + +func newfunc() func(int) int { return func(x int) int { return x } } + +func main() { + runtime.GOMAXPROCS(1) + var fail bool + + go f() + check([]int{1, 4, 5, 4}) + + a := accum(0) + b := accum(1) + go g(a, b) + check([]int{2, 4, 6, 9}) + + go h() + check([]int{100, 200, 101, 201, 500, 101, 201, 500}) + + memstats := new(runtime.MemStats) + runtime.ReadMemStats(memstats) + n0 := memstats.Mallocs + + x, y := newfunc(), newfunc() + if x(1) != 1 || y(2) != 2 { + println("newfunc returned broken funcs") + fail = true + } + + runtime.ReadMemStats(memstats) + if n0 != memstats.Mallocs { + println("newfunc allocated unexpectedly") + fail = true + } + + ff(1) + + if fail { + panic("fail") + } +} + +func ff(x int) { + call(func() { + _ = x + }) +} + +func call(func()) { +} |