Useless assignment to field¶
ID: go/useless-assignment-to-fieldKind: problemSecurity severity: Severity: warningPrecision: very-highTags: - quality - maintainability - useless-code - external/cwe/cwe-563Query suites: - go-code-quality.qls - go-security-and-quality.qls
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A value is assigned to a field, but its value is never read. This means that the assignment has no effect, and could indicate a logic error or incomplete code.
Recommendation¶
Examine the assignment closely to determine whether it is redundant, or whether it is perhaps a symptom of another bug.
Example¶
The following example shows a simplestruct type wrapping an integer counter with a methodreset that sets the counter to zero.
packagemaintypecounterstruct{valint}func(ccounter)reset(){c.val=0}
However, the receiver variable ofreset is declared to be of typecounter, not*counter, so the receiver value is passed into the method by value, not by reference. Consequently, the method does not actually mutate its receiver as intended.
To fix this, change the type of the receiver variable to*counter:
packagemainfunc(c*counter)resetGood(){c.val=0}
References¶
Go Frequently Asked Questions:Should I define methods on values or pointers?
The Go Programming Language Specification:Method declarations.
Common Weakness Enumeration:CWE-563.