diff options
Diffstat (limited to 'libgo/go/database/sql/convert_test.go')
-rw-r--r-- | libgo/go/database/sql/convert_test.go | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/libgo/go/database/sql/convert_test.go b/libgo/go/database/sql/convert_test.go index a39c2c54fb..98af9fb64c 100644 --- a/libgo/go/database/sql/convert_test.go +++ b/libgo/go/database/sql/convert_test.go @@ -8,6 +8,7 @@ import ( "database/sql/driver" "fmt" "reflect" + "runtime" "testing" "time" ) @@ -279,3 +280,69 @@ func TestValueConverters(t *testing.T) { } } } + +// Tests that assigning to RawBytes doesn't allocate (and also works). +func TestRawBytesAllocs(t *testing.T) { + var tests = []struct { + name string + in interface{} + want string + }{ + {"uint64", uint64(12345678), "12345678"}, + {"uint32", uint32(1234), "1234"}, + {"uint16", uint16(12), "12"}, + {"uint8", uint8(1), "1"}, + {"uint", uint(123), "123"}, + {"int", int(123), "123"}, + {"int8", int8(1), "1"}, + {"int16", int16(12), "12"}, + {"int32", int32(1234), "1234"}, + {"int64", int64(12345678), "12345678"}, + {"float32", float32(1.5), "1.5"}, + {"float64", float64(64), "64"}, + {"bool", false, "false"}, + } + + buf := make(RawBytes, 10) + test := func(name string, in interface{}, want string) { + if err := convertAssign(&buf, in); err != nil { + t.Fatalf("%s: convertAssign = %v", name, err) + } + match := len(buf) == len(want) + if match { + for i, b := range buf { + if want[i] != b { + match = false + break + } + } + } + if !match { + t.Fatalf("%s: got %q (len %d); want %q (len %d)", name, buf, len(buf), want, len(want)) + } + } + + n := testing.AllocsPerRun(100, func() { + for _, tt := range tests { + test(tt.name, tt.in, tt.want) + } + }) + + // The numbers below are only valid for 64-bit interface word sizes, + // and gc. With 32-bit words there are more convT2E allocs, and + // with gccgo, only pointers currently go in interface data. + // So only care on amd64 gc for now. + measureAllocs := runtime.GOARCH == "amd64" && runtime.Compiler == "gc" + + if n > 0.5 && measureAllocs { + t.Fatalf("allocs = %v; want 0", n) + } + + // This one involves a convT2E allocation, string -> interface{} + n = testing.AllocsPerRun(100, func() { + test("string", "foo", "foo") + }) + if n > 1.5 && measureAllocs { + t.Fatalf("allocs = %v; want max 1", n) + } +} |