codegen: move generated test helpers to new 'db_test.go' file

pkg/codegen/pkg.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"text/template"
 
 	. "git.offline-twitter.com/offline-labs/gas-stack/pkg/flowutils"
 )
@@ -39,6 +40,11 @@ func InitPkg(opts PkgOpts) {
 	PanicIf(os.WriteFile("pkg/db/schema.sql", Must(tpl.ReadFile("tpl/schema.sql")), 0o664))
 	PanicIf(os.WriteFile("pkg/db/db.go", Must(tpl.ReadFile("tpl/db.go.tpl")), 0o664))
 
+	dbTest := Must(os.Create("pkg/db/db_test.go"))
+	defer MustClose(dbTest)
+	t := Must(template.ParseFS(tpl, "tpl/db_test.go.tpl"))
+	PanicIf(t.Execute(dbTest, opts))
+
 	PanicIf(os.WriteFile("sample_data/mount.sh", Must(tpl.ReadFile("tpl/mount.sh")), 0o775))
 	PanicIf(os.WriteFile("sample_data/reset.sh", Must(tpl.ReadFile("tpl/reset.sh")), 0o775))