S1009: handle shadowed len

Closes gh-1181 (cherry picked from commit e3efe9b)
dominikh · May 16, 2022 · ce49d7b · ce49d7b
1 parent b6a3bc8
commit ce49d7b
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Showing 2 changed files with 12 additions and 2 deletions.
diff --git a/simple/lint.go b/simple/lint.go
@@ -659,8 +659,7 @@ func CheckRedundantNilCheckWithLen(pass *analysis.Pass) (interface{}, error) {
 		if !ok {
 			return
 		}
-		yxFun, ok := yx.Fun.(*ast.Ident)
-		if !ok || yxFun.Name != "len" || len(yx.Args) != 1 {
+		if !code.IsCallTo(pass, yx, "len") {
 			return
 		}
 		yxArg, ok := yx.Args[knowledge.Arg("len.v")].(*ast.Ident)

diff --git a/simple/testdata/src/CheckRedundantNilCheckWithLen/nil-len.go b/simple/testdata/src/CheckRedundantNilCheckWithLen/nil-len.go
@@ -62,3 +62,14 @@ func fn() {
 	if s != nil && len(s) != len(ch) { // nil check is not redundant here
 	}
 }
+
+func fn3() {
+	var x []int
+
+	if x == nil || len(x) == 0 { //@ diag(`should omit nil check`)
+	}
+
+	len := func([]int) int { return 10 }
+	if x == nil || len(x) == 0 {
+	}
+}