fix: render the view "Back" lands on after the popup is reopened (closes #268)

tests/backNavigation.test.js

@@ -0,0 +1,329 @@
+// Back after reopening the popup (#268).
+//
+// A reopened popup renders the wallet list and the one view it restores
+// onto; every other view is still the blank static template from
+// index.html. goBack() used to only unhide its target, so Back landed on
+// that blank template for any view the popup had not rendered in this page
+// load. These tests drive the real goBack() with the real router wired to
+// recording view modules, so what is asserted is which view render ran —
+// the thing that was missing.
+//
+// The rendering itself is asserted against the real popup in a real
+// browser by tests/e2e/run.js; here the DOM is a stub, because goBack()
+// only needs showView() to work.
+
+const els = new Map();
+
+function fakeEl() {
+    return {
+        textContent: "",
+        innerHTML: "",
+        classList: {
+            toggle() {},
+            add() {},
+            remove() {},
+            contains: () => false,
+        },
+        remove() {},
+    };
+}
+
+globalThis.document = {
+    getElementById(id) {
+        if (!els.has(id)) els.set(id, fakeEl());
+        return els.get(id);
+    },
+};
+
+// helpers.js pulls in state.js, which reads chrome.storage.local at load.
+globalThis.chrome = {
+    storage: { local: { get: async () => ({}), set: async () => {} } },
+};
+
+const {
+    showView,
+    goBack,
+    setBackRenderer,
+    pushCurrentView,
+} = require("../src/popup/views/helpers");
+const {
+    makeBackRenderer,
+    markViewRendered,
+    resetRenderedViews,
+} = require("../src/popup/viewRouter");
+const { state } = require("../src/shared/state");
+
+const ADDRESS = "0x1111111111111111111111111111111111111111";
+const TOKEN = "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48";
+
+let calls;
+
+// Stand-ins for the view modules. Each records itself and then shows its
+// view, which is what every real view render ends with — so the assertions
+// can tell "rendered and shown" apart from "merely unhidden".
+function recorder(name, view) {
+    return () => {
+        calls.push(name);
+        showView(view);
+    };
+}
+
+function makeViews() {
+    return {
+        main: { show: recorder("main", "main") },
+        addressDetail: { show: recorder("addressDetail", "address") },
+        addressToken: { show: recorder("addressToken", "address-token") },
+        receive: { show: recorder("receive", "receive") },
+        settings: { show: recorder("settings", "settings") },
+        settingsAddToken: {
+            show: recorder("settingsAddToken", "settings-addtoken"),
+        },
+        confirmTx: { restore: recorder("confirmTx", "confirm-tx") },
+        transactionDetail: {
+            render: recorder("transactionDetail", "transaction"),
+        },
+        txStatus: {
+            restoreWait: () => {
+                calls.push("waitTx");
+                showView("wait-tx");
+                return true;
+            },
+            renderSuccess: recorder("successTx", "success-tx"),
+            renderError: recorder("errorTx", "error-tx"),
+        },
+    };
+}
+
+// The popup as it stands just after a reopen: one wallet with one address,
+// the view the popup restored onto, and the stack behind it.
+//
+// A reopen is a fresh page load, so the record of what has been rendered
+// starts empty — that emptiness is what makes the Back path render at all.
+// Returns the view modules so a test can drive forward navigation through
+// the same recorders the router renders through.
+function reopenedOn(view, stack, extra) {
+    calls = [];
+    resetRenderedViews();
+    state.wallets = [
+        {
+            name: "Wallet 1",
+            addresses: [{ address: ADDRESS, balance: "0", tokenBalances: [] }],
+        },
+    ];
+    state.selectedWallet = 0;
+    state.selectedAddress = 0;
+    state.selectedToken = null;
+    state.viewData = null;
+    state.currentView = view;
+    state.viewStack = stack.slice();
+    Object.assign(state, extra || {});
+    // Restoring onto a view renders it, so the reopened popup has that one
+    // view on the page and nothing else.
+    markViewRendered(view);
+    const views = makeViews();
+    setBackRenderer(makeBackRenderer(state, views));
+    return views;
+}
+
+// The reproduction from the issue, step for step.
+describe("Back onto a view the reopened popup never rendered", () => {
+    test("Back from settings renders the address detail underneath", () => {
+        reopenedOn("settings", ["main", "address"]);
+        goBack();
+        expect(calls).toEqual(["addressDetail"]);
+        expect(state.currentView).toBe("address");
+        expect(state.viewStack).toEqual(["main"]);
+    });
+
+    test("Back onto the token detail renders it", () => {
+        reopenedOn("settings", ["main", "address", "address-token"], {
+            selectedToken: TOKEN,
+        });
+        goBack();
+        expect(calls).toEqual(["addressToken"]);
+        expect(state.currentView).toBe("address-token");
+    });
+
+    test("Back onto Receive renders it", () => {
+        reopenedOn("settings", ["main", "address", "receive"]);
+        goBack();
+        expect(calls).toEqual(["receive"]);
+        expect(state.currentView).toBe("receive");
+    });
+
+    test("Back onto the transaction detail renders it", () => {
+        reopenedOn("settings", ["main", "transaction"], {
+            viewData: { tx: { hash: "0xdead" } },
+        });
+        goBack();
+        expect(calls).toEqual(["transactionDetail"]);
+        expect(state.currentView).toBe("transaction");
+    });
+
+    test("Back onto the transaction confirmation restores it", () => {
+        reopenedOn("settings", ["main", "confirm-tx"], {
+            viewData: { pendingTx: { to: ADDRESS, amount: "1" } },
+        });
+        goBack();
+        expect(calls).toEqual(["confirmTx"]);
+        expect(state.currentView).toBe("confirm-tx");
+    });
+
+    test("Back onto the success screen renders it", () => {
+        reopenedOn("settings", ["main", "success-tx"], {
+            viewData: { hash: "0xdead" },
+        });
+        goBack();
+        expect(calls).toEqual(["successTx"]);
+        expect(state.currentView).toBe("success-tx");
+    });
+
+    test("Back onto the failure screen renders it", () => {
+        reopenedOn("settings", ["main", "error-tx"], {
+            viewData: { message: "execution reverted" },
+        });
+        goBack();
+        expect(calls).toEqual(["errorTx"]);
+        expect(state.currentView).toBe("error-tx");
+    });
+
+    test("Back onto Home renders the wallet list", () => {
+        reopenedOn("settings", ["main"]);
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+
+    test("Back with an empty stack renders Home", () => {
+        reopenedOn("settings", []);
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+});
+
+// The guards are restoreView()'s, so a popped view whose backing data is
+// gone lands on Home rather than on an empty template.
+describe("Back onto a view whose backing data is gone", () => {
+    test("the token detail with no token selected falls back to Home", () => {
+        reopenedOn("settings", ["main", "address-token"]);
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+
+    test("the transaction detail with no transaction falls back to Home", () => {
+        reopenedOn("settings", ["main", "transaction"]);
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+
+    test("the confirmation with no pending transaction falls back to Home", () => {
+        reopenedOn("settings", ["main", "confirm-tx"]);
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+
+    test("an address view with no address selected falls back to Home", () => {
+        reopenedOn("settings", ["main", "receive"], {
+            selectedAddress: null,
+        });
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+
+    test("the success screen with no transaction hash falls back to Home", () => {
+        reopenedOn("settings", ["main", "success-tx"]);
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+
+    test("the failure screen with no message falls back to Home", () => {
+        reopenedOn("settings", ["main", "error-tx"]);
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+
+    test("a wait that can no longer be resumed falls back to Home", () => {
+        reopenedOn("settings", ["main", "wait-tx"]);
+        const views = makeViews();
+        views.txStatus.restoreWait = () => false;
+        setBackRenderer(makeBackRenderer(state, views));
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+});
+
+// Forward navigation renders as it goes, and a second render would re-fetch
+// and clobber whatever the view holds — an unsaved edit, a request in
+// flight. So the Back path renders only a view this page load has never
+// rendered, and merely unhides every other one: the views it does not
+// render from persisted state, and the views already on the page.
+describe("what the Back path leaves alone", () => {
+    test("forward navigation renders nothing by itself", () => {
+        reopenedOn("address", ["main"]);
+        pushCurrentView();
+        showView("send");
+        expect(calls).toEqual([]);
+        expect(state.viewStack).toEqual(["main", "address"]);
+    });
+
+    test("Back onto a live-session view only unhides it", () => {
+        reopenedOn("confirm-tx", ["main", "address", "send"]);
+        goBack();
+        expect(calls).toEqual([]);
+        expect(state.currentView).toBe("send");
+    });
+
+    test("Back renders its target exactly once", () => {
+        reopenedOn("settings", ["main", "address"]);
+        goBack();
+        expect(calls.filter((c) => c === "addressDetail")).toHaveLength(1);
+    });
+
+    test("Back onto a view this page load already rendered only unhides it", () => {
+        const views = reopenedOn("main", []);
+        pushCurrentView();
+        views.addressDetail.show();
+        pushCurrentView();
+        views.settings.show();
+        calls = [];
+        goBack();
+        expect(calls).toEqual([]);
+        expect(state.currentView).toBe("address");
+    });
+
+    // The unit mirror of the regression the browser suite pins: Settings
+    // reassigns its fields from persisted state on every render, so a
+    // re-render on the way back discards an edit the user has not saved.
+    test("Back onto Settings visited earlier in this page load does not re-render it", () => {
+        const views = reopenedOn("main", []);
+        pushCurrentView();
+        views.settings.show();
+        pushCurrentView();
+        views.settingsAddToken.show();
+        calls = [];
+        goBack();
+        expect(calls).toEqual([]);
+        expect(state.currentView).toBe("settings");
+    });
+
+    // Home is the deliberate exception, unchanged from the popup's
+    // behaviour before the router existed: it re-renders on every Back so
+    // the wallet list reflects what changed while the user was away.
+    test("Back onto Home renders it again even when it is already on the page", () => {
+        const views = reopenedOn("main", []);
+        pushCurrentView();
+        views.addressDetail.show();
+        calls = [];
+        goBack();
+        expect(calls).toEqual(["main"]);
+        expect(state.currentView).toBe("main");
+    });
+});