SA9010: Conversion of uncomparable type to error (proposal)#1696
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klauspost wants to merge 1 commit intodominikh:masterfrom
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SA9010: Conversion of uncomparable type to error (proposal)#1696klauspost wants to merge 1 commit intodominikh:masterfrom
klauspost wants to merge 1 commit intodominikh:masterfrom
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Converting a value of an uncomparable type to the error interface
can lead to runtime panics when error values are compared. Types containing
slices, maps, or function fields are not comparable.
For example:
type MyError struct { Details []string }
func (e MyError) Error() string { return "" }
a, b := error(MyError{}), error(MyError{})
fmt.Println(a == b) // panic: comparing uncomparable type
To avoid this, either use a pointer receiver or wrap the error.
Disclaimer: AI Assisted. Human Reviewed.
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Converting a value of an uncomparable type to the error interface can lead to runtime panics when error values are compared. Types containing slices, maps, or function fields are not comparable.
For example:
To avoid this, either use a pointer receiver or wrap the error.
This seemed to belong in the "Dubious code constructs that have a high probability of being wrong" section.
It is a foot-gun waiting to blow up. You can argue that you shouldn't be comparing these in the first place, but you can end up with these from different sources, and you may have people trying to
a == error(c)wherec := MyError{}to work around the compiler error.Disclaimer: AI Assisted. Human Reviewed.