feat(checker): port other checkers over

Signed-off-by: Xe Iaso <me@xeiaso.net>

lib/checker/headerexists/factory_test.go

@@ -0,0 +1,60 @@
+package headerexists
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestFactoryGood(t *testing.T) {
+	files, err := os.ReadDir("./testdata/good")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	fac := Factory{}
+
+	for _, fname := range files {
+		t.Run(fname.Name(), func(t *testing.T) {
+			data, err := os.ReadFile(filepath.Join("testdata", "good", fname.Name()))
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if err := fac.Valid(t.Context(), json.RawMessage(data)); err != nil {
+				t.Fatal(err)
+			}
+		})
+	}
+}
+
+func TestFactoryBad(t *testing.T) {
+	files, err := os.ReadDir("./testdata/bad")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	fac := Factory{}
+
+	for _, fname := range files {
+		t.Run(fname.Name(), func(t *testing.T) {
+			data, err := os.ReadFile(filepath.Join("testdata", "bad", fname.Name()))
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			t.Run("Build", func(t *testing.T) {
+				if _, err := fac.Build(t.Context(), json.RawMessage(data)); err == nil {
+					t.Fatal(err)
+				}
+			})
+
+			t.Run("Valid", func(t *testing.T) {
+				if err := fac.Valid(t.Context(), json.RawMessage(data)); err == nil {
+					t.Fatal(err)
+				}
+			})
+		})
+	}
+}