add bpf2go test emit-and-load specs+bpf objects

This commit extends `api_test.go` to check whether specs and bpf objects
are correctly loaded. It also accounts for the new Variable/VariableSpec
in the test.
In addition, this commit adds a bpf2go test in `output_test.go` to verify
that all the listed bpf objects (i.e., variables, maps and programs) are
emitted. The tests looks for the output program, stored in a buffer, which
should contain the expected declarations.

This commits introduces further checks in the `api_test.go`

Signed-off-by: Simone Magnani <[email protected]>

cmd/bpf2go/gen/output_test.go

@@ -97,3 +97,25 @@ func TestCustomIdentifier(t *testing.T) {
 	qt.Assert(t, qt.IsNil(err))
 	qt.Assert(t, qt.StringContains(buf.String(), "DO_THING"))
 }
+
+func TestBpfObjects(t *testing.T) {
+	var buf bytes.Buffer
+	args := GenerateArgs{
+		Package:   "foo",
+		Stem:      "bar",
+		Maps:      []string{"map1"},
+		Variables: []string{"var_1"},
+		Programs:  []string{"prog_foo_1"},
+		Output:    &buf,
+	}
+	err := Generate(args)
+	qt.Assert(t, qt.IsNil(err))
+
+	qt.Assert(t, qt.StringContains(buf.String(), "Map1 *ebpf.MapSpec `ebpf:\"map1\"`"))
+	qt.Assert(t, qt.StringContains(buf.String(), "Var1 *ebpf.VariableSpec `ebpf:\"var_1\"`"))
+	qt.Assert(t, qt.StringContains(buf.String(), "ProgFoo1 *ebpf.ProgramSpec `ebpf:\"prog_foo_1\"`"))
+
+	qt.Assert(t, qt.StringContains(buf.String(), "Map1 *ebpf.Map `ebpf:\"map1\"`"))
+	qt.Assert(t, qt.StringContains(buf.String(), "Var1 *ebpf.Variable `ebpf:\"var_1\"`"))
+	qt.Assert(t, qt.StringContains(buf.String(), "ProgFoo1 *ebpf.Program `ebpf:\"prog_foo_1\"`"))
+}

cmd/bpf2go/test/api_test.go

@@ -18,6 +18,18 @@ func TestLoadingSpec(t *testing.T) {
 	if spec == nil {
 		t.Fatal("Got a nil spec")
 	}
+
+	if spec.Programs == nil {
+		t.Error("Got a nil spec for programs")
+	}
+
+	if spec.Maps == nil {
+		t.Error("Got a nil spec for maps")
+	}
+
+	if spec.Variables == nil {
+		t.Error("Got a nil spec for variables")
+	}
 }
 
 func TestLoadingObjects(t *testing.T) {
@@ -36,6 +48,10 @@ func TestLoadingObjects(t *testing.T) {
 	if objs.Map1 == nil {
 		t.Error("Loading returns an object with nil maps")
 	}
+
+	if objs.MyConstant == nil || objs.StructConst == nil {
+		t.Error("Loading returns an object with nil variables")
+	}
 }
 
 func TestTypes(t *testing.T) {