added FP fixes for racy append to slice and map rules

go/racy-append-to-slice.go

@@ -23,6 +23,9 @@ func main() {
 
 	res6 := appendToSlice_FP4()
 	printResults(res6)
+
+	res7 := appendToSlice_FP5()
+	printResults(res7)
 }
 
 func appendToSlice1() []int {
@@ -146,6 +149,28 @@ func appendToSlice_FP4() []int {
 	return r
 }
 
+func appendToSlice_FP5() []int {
+	// FP: The `append` is done inside a defer lock
+	var wg sync.WaitGroup
+	var rMut sync.Mutex
+	var r []int
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func(iCpy int) {
+			defer wg.Done()
+			m := iCpy * 2
+			// ok: racy-append-to-slice
+			rMut.Lock()
+			defer rMut.Unlock()
+			r = append(r, m)
+		}(i)
+	}
+
+	wg.Wait()
+
+	return r
+}
+
 func printResults(results []int) {
 	for v, _ := range results {
 		fmt.Println(v)

go/racy-append-to-slice.yaml

@@ -48,3 +48,7 @@ rules:
           $MUTEX.Lock()
           ...
           $MUTEX.Unlock()
+    - pattern-not-inside: |
+          $MUTEX.Lock()
+          defer $MUTEX.Unlock()
+          ...

go/racy-write-to-map.go

@@ -39,6 +39,10 @@ func main() {
 	fmt.Println("appendToMap_FP4:")
 	res6 := appendToMap_FP4()
 	printMap(res6)
+
+	fmt.Println("appendToMap_FP5:")
+	res7 := appendToMap_FP5()
+	printMap(res7)
 }
 
 func appendToMap1() map[int]string {
@@ -160,6 +164,28 @@ func appendToMap_FP4() map[int]string {
 	return r
 }
 
+func appendToMap_FP5() map[int]string {
+	// FP: The map write is done inside a defer lock
+	var wg sync.WaitGroup
+	r := make(map[int]string)
+	var rMut sync.Mutex
+
+	for i := 0; i < 10; i++ {
+		wg.Add(1)
+		go func(iCpy int) {
+			defer wg.Done()
+			// ok: racy-write-to-map
+			rMut.Lock()
+			defer rMut.Unlock()
+			r[iCpy] = fmt.Sprintf("number-%d", iCpy)
+		}(i)
+	}
+
+	wg.Wait()
+
+	return r
+}
+
 func printMap(results map[int]string) {
 	for k, v := range results {
 		fmt.Printf("key: %d, val: %s\n", k, v)

go/racy-write-to-map.yaml

@@ -35,3 +35,7 @@ rules:
           $MUTEX.Lock()
           ...
           $MUTEX.Unlock()
+    - pattern-not-inside: |
+          $MUTEX.Lock()
+          defer $MUTEX.Unlock()
+          ...