2db4579b6f
The long-form (with comma-ok) ones were already fixed but the short-form ones were not because they were in a completely different code path. This PR also refactors the code so that both short-form and long-form are now merged in the same function. N.B: even though most (all?) cases seem to now be supported, one of them still yields a result that does not satisfy reflect's Implements method yet. It does not prevent the resulting assertion to be usable though. N.B2: the code path for the third-form (_, ok) hasn't been fixed and/or refactored yet. Fixes #919
61 lines
1.1 KiB
Go
61 lines
1.1 KiB
Go
package main
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import (
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"fmt"
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"reflect"
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"time"
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)
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type TestStruct struct{}
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func (t TestStruct) String() string {
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return "hello world"
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}
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func main() {
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aType := reflect.TypeOf((*fmt.Stringer)(nil)).Elem()
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var t interface{}
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t = time.Nanosecond
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s, ok := t.(fmt.Stringer)
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if !ok {
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fmt.Println("time.Nanosecond does not implement fmt.Stringer")
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return
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}
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fmt.Println(s.String())
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fmt.Println(t.(fmt.Stringer).String())
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bType := reflect.TypeOf(time.Nanosecond)
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fmt.Println(bType.Implements(aType))
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t = 42
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foo, ok := t.(fmt.Stringer)
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if !ok {
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fmt.Println("42 does not implement fmt.Stringer")
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} else {
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fmt.Println("42 implements fmt.Stringer")
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}
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_ = foo
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var tt interface{}
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tt = TestStruct{}
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ss, ok := tt.(fmt.Stringer)
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if !ok {
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fmt.Println("TestStuct does not implement fmt.Stringer")
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return
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}
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fmt.Println(ss.String())
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fmt.Println(tt.(fmt.Stringer).String())
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// TODO(mpl): uncomment when fixed
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// cType := reflect.TypeOf(TestStruct{})
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// fmt.Println(cType.Implements(aType))
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}
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// Output:
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// 1ns
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// 1ns
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// true
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// 42 does not implement fmt.Stringer
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// hello world
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// hello world
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