adds defer rule

testdata/defer.go

@@ -0,0 +1,28 @@
+package fixtures
+
+import "errors"
+
+type tt int
+
+func (t tt) m() {}
+
+func deferrer() {
+	for {
+		go func() {
+			defer println()
+		}()
+		defer func() {}() // MATCH /prefer not to defer inside loops/
+	}
+
+	defer tt.m() // MATCH /be careful when deferring calls to methods without pointer receiver/
+
+	defer func() error {
+		return errors.New("error") //MATCH /return in a defer function has no effect/
+	}()
+
+	defer recover()
+
+	recover() //MATCH /recover must be called inside a deferred function/
+
+	defer deferrer()
+}