test: correctly close all Maps and Programs in the test suite

Since omitting Map and Program.Close() is generally considered an error,
clean up all cases in the test suite.

These were found by adding runtime.GC() at the end of a TestMain()
in all packages in the repository.

The plan is to follow up with some instrumentation that allows the caller
to get notified when the sys.FD finalizer successfully closes a file
descriptor during a GC round.

Signed-off-by: Timo Beckers <timo@isovalent.com>

collection_test.go

@@ -106,10 +106,12 @@ func TestCollectionSpecLoadCopy(t *testing.T) {
 	if err != nil {
 		t.Fatal("Loading original spec:", err)
 	}
+	defer objs.Prog.Close()
 
 	if err := spec2.LoadAndAssign(&objs, nil); err != nil {
 		t.Fatal("Loading copied spec:", err)
 	}
+	defer objs.Prog.Close()
 }
 
 func TestCollectionSpecRewriteMaps(t *testing.T) {
@@ -309,6 +311,9 @@ func TestCollectionSpecMapReplacements_SpecMismatch(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	// Map fd is duplicated by MapReplacements, this one can be safely closed.
+	defer newMap.Close()
+
 	coll, err := NewCollectionWithOptions(cs, CollectionOptions{
 		MapReplacements: map[string]*Map{
 			"test-map": newMap,
@@ -365,6 +370,8 @@ func TestCollectionSpec_LoadAndAssign_LazyLoading(t *testing.T) {
 	if err := spec.LoadAndAssign(&objs, nil); err != nil {
 		t.Fatal("Assign loads a map or program that isn't requested in the struct:", err)
 	}
+	defer objs.Prog.Close()
+	defer objs.Map.Close()
 
 	if objs.Prog == nil {
 		t.Error("Program is nil")
@@ -572,6 +579,8 @@ func ExampleCollectionSpec_LoadAndAssign() {
 	if err := spec.LoadAndAssign(&objs, nil); err != nil {
 		panic(err)
 	}
+	defer objs.Program.Close()
+	defer objs.Map.Close()
 
 	fmt.Println(objs.Program.Type())
 	fmt.Println(objs.Map.Type())

elf_reader_test.go

@@ -480,6 +480,7 @@ func TestTailCall(t *testing.T) {
 			t.Fatal(err)
 		}
 		defer obj.TailMain.Close()
+		defer obj.ProgArray.Close()
 
 		ret, _, err := obj.TailMain.Test(make([]byte, 14))
 		testutils.SkipIfNotSupported(t, err)
@@ -518,6 +519,7 @@ func TestSubprogRelocation(t *testing.T) {
 			t.Fatal(err)
 		}
 		defer obj.Main.Close()
+		defer obj.HashMap.Close()
 
 		ret, _, err := obj.Main.Test(make([]byte, 14))
 		testutils.SkipIfNotSupported(t, err)

linker_test.go

@@ -45,6 +45,7 @@ func TestFindReferences(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
+	defer prog.Close()
 
 	ret, _, err := prog.Test(make([]byte, 14))
 	if err != nil {
@@ -90,6 +91,7 @@ func TestForwardFunctionDeclaration(t *testing.T) {
 		if err != nil {
 			t.Fatal(err)
 		}
+		defer prog.Close()
 
 		ret, _, err := prog.Test(make([]byte, 14))
 		if err != nil {

map_test.go

@@ -293,6 +293,7 @@ func TestBatchMapWithLock(t *testing.T) {
 		if err != nil {
 			t.Fatal("Can't parse ELF:", err)
 		}
+		defer coll.Close()
 
 		type spinLockValue struct {
 			Cnt     uint32
@@ -353,6 +354,7 @@ func TestMapWithLock(t *testing.T) {
 		if err != nil {
 			t.Fatal("Can't parse ELF:", err)
 		}
+		defer coll.Close()
 
 		type spinLockValue struct {
 			Cnt     uint32
@@ -1240,11 +1242,11 @@ func TestIterateMapInMap(t *testing.T) {
 		m       *Map
 		entries = parent.Iterate()
 	)
-	defer m.Close()
 
 	if !entries.Next(&key, &m) {
 		t.Fatal("Iterator encountered error:", entries.Err())
 	}
+	m.Close()
 
 	if key != 1 {
 		t.Error("Iterator didn't skip first entry")

prog_test.go

@@ -472,6 +472,7 @@ func TestProgramMarshaling(t *testing.T) {
 	if err := arr.Lookup(idx, &prog2); err != nil {
 		t.Fatal("Can't unmarshal program:", err)
 	}
+	defer prog2.Close()
 
 	if prog2 == nil {
 		t.Fatal("Unmarshalling set program to nil")