fix(09): WR-16 resolve model columns through embedded structs and explicit column tags

modules/cabana/model_fields_test.go

@@ -0,0 +1,86 @@
+package cabana
+
+import (
+	"reflect"
+	"testing"
+	"time"
+
+	"gorm.io/gorm"
+)
+
+type embeddedBase struct {
+	ID        uint      `gorm:"primarykey"`
+	CreatedAt time.Time `gorm:"column:created_at"`
+}
+
+type embeddedModel struct {
+	embeddedBase
+	Name string `gorm:"column:name"`
+}
+
+type gormModelRow struct {
+	gorm.Model
+	Name string `gorm:"column:name"`
+}
+
+type retaggedModel struct {
+	Name  string `gorm:"column:title"`
+	Title string `gorm:"column:name"`
+	Plain string
+}
+
+// TestModelHelpersLookThroughEmbeddedStructs pins WR-16: the reflection helpers
+// that resolve columns see fields promoted from an embedded struct such as
+// gorm.Model, so list rows keep their id and timestamps and a relation link
+// writes the real owner key instead of 0.
+func TestModelHelpersLookThroughEmbeddedStructs(t *testing.T) {
+	row := &embeddedModel{embeddedBase: embeddedBase{ID: 7, CreatedAt: time.Unix(1700000000, 0).UTC()}, Name: "n"}
+	if got := primaryColumn(row); got != "id" {
+		t.Fatalf("primaryColumn = %q, want id (the embedded primarykey field)", got)
+	}
+	if got := pkUint(row); got != 7 {
+		t.Fatalf("pkUint = %d, want 7", got)
+	}
+	cols := modelColumns(row)
+	for _, want := range []string{"created_at", "name"} {
+		if _, ok := cols[want]; !ok {
+			t.Fatalf("modelColumns = %v, missing %s", cols, want)
+		}
+	}
+	projected := projectRow(row, nil, []ListColumn{{Key: "name"}, {Key: "created_at"}})
+	if projected["id"] != uint(7) || projected["name"] != "n" || projected["created_at"] == nil {
+		t.Fatalf("projectRow = %#v, want the embedded id and created_at", projected)
+	}
+	if castPK(row, 9) != uint(9) {
+		t.Fatalf("castPK = %#v", castPK(row, 9))
+	}
+
+	gm := &gormModelRow{Model: gorm.Model{ID: 11}, Name: "g"}
+	if primaryColumn(gm) != "id" || pkUint(gm) != 11 {
+		t.Fatalf("gorm.Model primary key = %q/%d, want id/11", primaryColumn(gm), pkUint(gm))
+	}
+	if !fieldByColumn(reflect.ValueOf(gm).Elem(), "updated_at").IsValid() {
+		t.Fatal("gorm.Model's UpdatedAt is not reachable by column")
+	}
+}
+
+// TestFieldByColumnTagBeatsGoName pins the other half of WR-16: a field with an
+// explicit column tag is matched by that tag alone, never by its Go name.
+func TestFieldByColumnTagBeatsGoName(t *testing.T) {
+	row := retaggedModel{Name: "in-title-column", Title: "in-name-column", Plain: "p"}
+	v := reflect.ValueOf(row)
+	if got := fieldByColumn(v, "name"); !got.IsValid() || got.String() != "in-name-column" {
+		t.Fatalf("column name resolved to %v, want the field tagged column:name", got)
+	}
+	if got := fieldByColumn(v, "title"); !got.IsValid() || got.String() != "in-title-column" {
+		t.Fatalf("column title resolved to %v, want the field tagged column:title", got)
+	}
+	if got := fieldByColumn(v, "plain"); !got.IsValid() || got.String() != "p" {
+		t.Fatalf("an untagged field must still match its Go name case-insensitively, got %v", got)
+	}
+	if got := fieldByColumn(reflect.ValueOf(struct {
+		Name string `gorm:"column:title"`
+	}{Name: "x"}), "name"); got.IsValid() {
+		t.Fatalf("a tagged field matched by its Go name: %v", got)
+	}
+}