Fix closeafterusage linter for underscores in assign statements

Also adds some additional test cases encountered

tools/analyzers/closeafterusagecheck/closeafterusagecheck.go

@@ -2,7 +2,6 @@ package closeafterusagecheck
 
 import (
 	"flag"
-	"fmt"
 	"go/ast"
 	"strings"
 
@@ -114,7 +113,7 @@ func Analyzer() *analysis.Analyzer {
 					for _, expr := range s.Lhs {
 						foundType := pass.TypesInfo.TypeOf(expr)
 						if foundType == nil {
-							return false
+							continue
 						}
 
 						varTypeString := foundType.String()
@@ -205,10 +204,3 @@ func min(x int, y int) int {
 	}
 	return x
 }
-
-func printTypes(nodes []ast.Node) {
-	for _, n := range nodes {
-		fmt.Printf("%T, ", n)
-	}
-	fmt.Println()
-}

tools/analyzers/closeafterusagecheck/testdata/src/notimmediatelyclosed/notimmediatelyclosed.go

@@ -9,10 +9,18 @@ type SomeIterator struct{}
 func (si *SomeIterator) Close() {
 }
 
+func (si *SomeIterator) Err() error {
+	return nil
+}
+
 func (si *SomeIterator) Next() any {
 	return nil
 }
 
+func (si *SomeIterator) Cursor() (int, error) {
+	return 42, nil
+}
+
 func MissingNonDeferClose() {
 	si := CreateIterator() // want "variable MissingNonDeferClose.si is missing required non-defer-ed"
 	defer si.Close()
@@ -109,6 +117,44 @@ func SentToFunctionUnderSwitch() {
 	}
 }
 
+func AccessedAfterLoop() error {
+	cur := 0
+	for {
+		si, err := CreateIteratorOrError()
+		if err != nil {
+			return nil
+		}
+
+		for tpl := si.Next(); tpl != nil; tpl = si.Next() {
+			// do nothing
+		}
+		if si.Err() != nil {
+			return si.Err()
+		}
+
+		if cur == 0 {
+			si.Close()
+			continue
+		}
+
+		cur, err = si.Cursor()
+		si.Close()
+
+		if err != nil {
+			return err
+		}
+		fmt.Println(cur)
+	}
+}
+
+func AccessedDirectly() error {
+	var err error
+	si := CreateIterator()
+	_, err = si.Cursor()
+	si.Close()
+	return err
+}
+
 func ThirdFunction(si *SomeIterator) error {
 	return nil
 }
@@ -120,3 +166,7 @@ func AnotherFunction(si *SomeIterator) {
 func CreateIterator() *SomeIterator {
 	return &SomeIterator{}
 }
+
+func CreateIteratorOrError() (*SomeIterator, error) {
+	return &SomeIterator{}, nil
+}