Fix query param date bug (#12239)

* Add Cypress test for #12228 (#12235)

* fix logic to check if we'll use fieldValueWidget while parsing query params

Co-authored-by: Damon P. Cortesi <d.lifehacker@gmail.com>

frontend/src/metabase/parameters/components/Parameters.jsx

@@ -71,10 +71,14 @@ export default class Parameters extends Component {
         const queryParam = query && query[parameter.slug];
         if (queryParam != null || parameter.default != null) {
           let value = queryParam != null ? queryParam : parameter.default;
-          if (parameter.hasOnlyFieldTargets && value && !Array.isArray(value)) {
-            // FieldValuesWidget always produces an array. If this param has
-            // only field targets we'll use that widget, so we should start with
-            // an array to match.
+
+          // ParameterValueWidget uses FieldValuesWidget if there's no available
+          // date widget and all targets are fields. This matches that logic.
+          const willUseFieldValuesWidget =
+            parameter.hasOnlyFieldTargets && !/^date\//.test(parameter.type);
+          if (willUseFieldValuesWidget && value && !Array.isArray(value)) {
+            // FieldValuesWidget always produces an array. If we'll use that
+            // widget, we should start with an array to match.
             value = [value];
           }
           const fieldIds = parameter.field_ids || [];

frontend/test/metabase/scenarios/question/native.cy.spec.js

-import { signInAsNormalUser, restore, popover } from "__support__/cypress";
+import {
+  signInAsNormalUser,
+  restore,
+  popover,
+  modal,
+} from "__support__/cypress";
 
 describe("scenarios > question > native", () => {
   before(restore);
@@ -150,4 +155,39 @@ describe("scenarios > question > native", () => {
     cy.get(".NativeQueryEditor .Icon-play").click();
     cy.contains("18,760");
   });
+
+  it("can load a question with a date filter (from issue metabase#12228)", () => {
+    cy.request("POST", "/api/card", {
+      name: "Test Question",
+      dataset_query: {
+        type: "native",
+        native: {
+          query: "select count(*) from orders where {{created_at}}",
+          "template-tags": {
+            created_at: {
+              id: "6b8b10ef-0104-1047-1e1b-2492d5954322",
+              name: "created_at",
+              "display-name": "Created at",
+              type: "dimension",
+              dimension: ["field-id", 15],
+              "widget-type": "date/month-year",
+            },
+          },
+        },
+        database: 1,
+      },
+      display: "scalar",
+      description: null,
+      visualization_settings: {},
+      collection_id: null,
+      result_metadata: null,
+      metadata_checksum: null,
+    }).then(response => {
+      cy.visit(`/question/${response.body.id}?created_at=2020-01`);
+      modal()
+        .contains("Okay")
+        .click();
+      cy.contains("580");
+    });
+  });
 });