internal/database: use generics for Collect functions

Reimplement some reflection-based collection functions to
use generics.

In some cases we still need reflection, but at least we
can provide a type-safe wrapper with generics.

Change-Id: Id95949a7a22ee687166ecdfc1191150d79568889
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/389657
Trust: Jonathan Amsterdam <jba@google.com>
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jamal Carvalho <jamal@golang.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/internal/database/database_test.go b/internal/database/database_test.go
index 2869d5c3..eda36ed0 100644
--- a/internal/database/database_test.go
+++ b/internal/database/database_test.go
@@ -449,8 +449,8 @@ func testTransactSerializable(ctx context.Context, t *testing.T) string {
 	type row struct {
 		Class, Value int
 	}
-	var rows []row
-	if err := testDB.CollectStructs(ctx, &rows, `SELECT class, value FROM ser ORDER BY id`); err != nil {
+	rows, err := CollectStructs[row](ctx, testDB, `SELECT class, value FROM ser ORDER BY id`)
+	if err != nil {
 		return err.Error()
 	}
 	const initialRows = 4
@@ -568,7 +568,7 @@ func TestCollectStrings(t *testing.T) {
 			t.Fatal(err)
 		}
 	}
-	got, err := testDB.CollectStrings(ctx, `SELECT s FROM test_cs`)
+	got, err := Collect1[string](ctx, testDB, `SELECT s FROM test_cs`)
 	if err != nil {
 		t.Fatal(err)
 	}