require format param name 'format' and no return values to reduce false-positives count

Author: jirfag

pkg/analyzer/analyzer.go

@@ -26,6 +26,10 @@ func run(pass *analysis.Pass) (interface{}, error) {
 	inspector.Preorder(nodeFilter, func(node ast.Node) {
 		funcDecl := node.(*ast.FuncDecl)
 
+		if res := funcDecl.Type.Results; res != nil && len(res.List) != 0 {
+			return
+		}
+
 		params := funcDecl.Type.Params.List
 		if len(params) < 2 { // [0] must be format (string), [1] must be args (...interface{})
 			return
@@ -40,6 +44,10 @@ func run(pass *analysis.Pass) (interface{}, error) {
 			return
 		}
 
+		if formatParamNames := params[len(params)-2].Names; len(formatParamNames) == 0 || formatParamNames[len(formatParamNames)-1].Name != "format" {
+			return
+		}
+
 		argsParamType, ok := params[len(params)-1].Type.(*ast.Ellipsis)
 		if !ok { // args are not ellipsis (...args)
 			return

testdata/src/p/p.go

@@ -8,7 +8,7 @@ func printfLikeButWithStrings(format string, args ...string) {}
 
 func printfLikeButWithBadFormat(format int, args ...interface{}) {}
 
-func secondArgIsNotEllipsis(arg1 string, arg2 int) {}
+func secondArgIsNotEllipsis(format string, arg int) {}
 
 func printfLikeButWithExtraInterfaceMethods(format string, args ...interface {
 	String() string
@@ -17,12 +17,14 @@ func printfLikeButWithExtraInterfaceMethods(format string, args ...interface {
 
 func prinfLikeFuncf(format string, args ...interface{}) {}
 
+func prinfLikeFuncWithReturnValue(format string, args ...interface{}) string {
+	return ""
+}
+
+func prinfLikeFuncWithAnotherFormatArgName(msg string, args ...interface{}) {}
+
 func prinfLikeFunc(format string, args ...interface{}) {} // want "printf-like formatting function"
 
 func prinfLikeFuncWithExtraArgs1(extraArg, format string, args ...interface{}) {} // want "printf-like formatting function"
 
 func prinfLikeFuncWithExtraArgs2(extraArg int, format string, args ...interface{}) {} // want "printf-like formatting function"
-
-func prinfLikeFuncWithReturnValue(format string, args ...interface{}) string { // want "printf-like formatting function"
-	return ""
-}