changes with app product stock

services/productVisibility_test.go

@@ -234,3 +234,122 @@ func TestReimportWithoutACategoryLeavesTheExistingOneAlone(t *testing.T) {
 		t.Errorf("a category-less import overwrote an existing category")
 	}
 }
+
+/*
+"If we have the stock, we can order it" — the customer app's browse rule.
+
+The products below are Suriya Store's Peelamedu shelf as it actually stood:
+three products listed, one with stock. Before this filter the app offered all
+three, so a shopper could order two chocolate bars the shop did not have.
+*/
+
+func names(products []models.Products) []string {
+	out := make([]string, 0, len(products))
+	for _, p := range products {
+		out = append(out, p.Productname)
+	}
+	return out
+}
+
+var peelamedu = []models.Products{
+	{Productid: 7084, Productname: "Cadbury 5 Star 9.8 g", Productstock: 0},
+	{Productid: 7085, Productname: "Cadbury 5 Star 18g", Productstock: 0},
+	{Productid: 7086, Productname: "Cadbury Dairy Milk 100g", Productstock: 25},
+}
+
+func TestOnlyProductsWithStockAreOffered(t *testing.T) {
+	got := InStockOnly(peelamedu, 1170)
+
+	if len(got) != 1 {
+		t.Fatalf("offered %d products, want 1: %v", len(got), names(got))
+	}
+	if got[0].Productid != 7086 {
+		t.Errorf("offered %d, want 7086 (the only one in stock)", got[0].Productid)
+	}
+}
+
+// An outlet with nothing in stock offers nothing — it does not fall back to
+// showing the shelf. An empty shop is the honest answer.
+func TestAnOutletWithNoStockOffersNothing(t *testing.T) {
+	empty := []models.Products{
+		{Productid: 7084, Productstock: 0},
+		{Productid: 7085, Productstock: 0},
+	}
+	if got := InStockOnly(empty, 1172); len(got) != 0 {
+		t.Errorf("offered %d products from an empty shelf", len(got))
+	}
+}
+
+// Without an outlet, GetProducts scopes its balance subquery to locationid 0,
+// which matches nothing and returns every product with Productstock 0. Filtering
+// there would empty the catalogue instead of leaving it unscoped.
+func TestAnUnscopedBrowseIsNotFiltered(t *testing.T) {
+	if got := InStockOnly(peelamedu, 0); len(got) != 3 {
+		t.Errorf("unscoped browse returned %d, want all 3 unfiltered", len(got))
+	}
+}
+
+// A negative balance is not stock. The ledger can go below zero when an "out"
+// exceeds what was received, and `> 0` must not read that as sellable.
+func TestANegativeBalanceIsNotStock(t *testing.T) {
+	oversold := []models.Products{{Productid: 7084, Productstock: -3}}
+	if got := InStockOnly(oversold, 1170); len(got) != 0 {
+		t.Errorf("an oversold product was offered for sale")
+	}
+}
+
+func TestFilteringDoesNotDisturbTheCallersSlice(t *testing.T) {
+	source := []models.Products{
+		{Productid: 1, Productstock: 0},
+		{Productid: 2, Productstock: 5},
+	}
+	_ = InStockOnly(source, 1170)
+	if len(source) != 2 || source[0].Productid != 1 || source[1].Productid != 2 {
+		t.Errorf("the input slice was modified: %+v", source)
+	}
+}
+
+func (f *fakeProductRepo) GetSubcategories(categoryID int) ([]models.Subcategory, error) {
+	return nil, nil
+}
+
+// Returns (nil, nil) so GetProductsBySubcategory falls through to its plain
+// {"details": ...} shape. The tenant header block is not what this test is about.
+func (f *fakeProductRepo) GetTenantInfo(tenantID, applocationID int) (map[string]interface{}, error) {
+	return nil, nil
+}
+
+func (f *fakeProductRepo) GetProducts(params models.ProductFilter) ([]models.Products, error) {
+	f.calls = append(f.calls, "GetProducts")
+	return peelamedu, nil
+}
+
+// The filter has to be WIRED, not merely written.
+//
+// The tests above exercise InStockOnly directly, which would keep passing if
+// nobody called it. This goes through the endpoint the customer app actually
+// hits and asserts on what a shopper would be shown.
+func TestTheBrowseEndpointOffersOnlyStockedProducts(t *testing.T) {
+	repo := newFakeRepo()
+	svc := NewProductService(repo, &fakeCatalogueService{})
+
+	result, err := svc.GetProductsBySubcategory(models.ProductFilter{
+		CategoryID: 2, TenantID: 1135, LocationID: 1170,
+	})
+	if err != nil {
+		t.Fatalf("GetProductsBySubcategory: %v", err)
+	}
+
+	groups, _ := result["details"].([]models.SubcategoryProductResponse)
+	var offered []models.Products
+	for _, g := range groups {
+		offered = append(offered, g.Products...)
+	}
+
+	if len(offered) != 1 {
+		t.Fatalf("the app was offered %d products, want 1: %v", len(offered), names(offered))
+	}
+	if offered[0].Productid != 7086 {
+		t.Errorf("offered product %d, want 7086 — the only one Peelamedu has", offered[0].Productid)
+	}
+}