test: add unit tests for Logger.js

tests/Logger.test.js

@@ -0,0 +1,116 @@
+const fs = require("fs").promises;
+const {dialog} = require("electron");
+const Logger =  require("../modules/persistence/Logger");
+
+const downloadPath = "a/download/path";
+const savePath = "path/to/log";
+
+jest.mock('electron', () => ({
+    dialog: {
+        showSaveDialog: jest.fn().mockResolvedValue({canceled: false, filePath: "path/to/log"}),
+    },
+}));
+
+beforeEach(() => {
+    jest.clearAllMocks();
+    fs.writeFile = jest.fn().mockResolvedValue("");
+    console.log = jest.fn().mockImplementation(() => {});
+});
+
+describe("log", () => {
+    it("adds the line to the log", () => {
+        const instance = instanceBuilder();
+        instance.logs = {
+            "identifier": ["first line"]
+        }
+        instance.log("identifier", "second line");
+        expect(instance.logs.identifier).toEqual(["first line", "second line"]);
+    });
+    it("creates a new log if it doesn't exist", () => {
+        const instance = instanceBuilder();
+        instance.log("identifier", "first line");
+        expect(instance.logs["identifier"]).toEqual(["first line"]);
+    });
+    it("Replaces done and killed with readable values", () => {
+        const values = [{val: "done", res: "Download finished"}, {val: "killed", res: "Download stopped"}];
+        for(const value of values) {
+            const instance = instanceBuilder();
+            instance.log("identifier", value.val);
+            expect(instance.logs["identifier"]).toEqual([value.res]);
+        }
+    });
+    it("trims all new lines from the log line", () => {
+        const instance = instanceBuilder();
+        instance.log("identifier", "\nfirst line \na line break\n");
+        expect(instance.logs["identifier"]).toEqual(["first line a line break"]);
+    });
+    it("ignores the call if the line is empty or falsy", () => {
+        const instance = instanceBuilder();
+        const values = ["", null, undefined];
+        for(const value of values) {
+            instance.log("identifier", value);
+            expect(instance.logs["identifier"]).toBeUndefined();
+        }
+    })
+});
+
+describe("get", () => {
+    it("returns the log associated with the identifier", () => {
+        const instance = instanceBuilder();
+        const log =  ["first line", "second line"];
+        const identifier = "identifier";
+        instance.logs[identifier] = log;
+        expect(instance.get(identifier)).toEqual(log);
+    });
+});
+
+describe("clear", () => {
+    it("removes the log associated with the identifier", () => {
+        const instance = instanceBuilder();
+        const identifier = "identifier";
+        instance.logs[identifier] = ["first line"];
+        instance.clear(identifier);
+        expect(instance.logs[identifier]).toBeUndefined();
+    });
+});
+
+describe("save", () => {
+    it("saves the log", async () => {
+        const instance = instanceBuilder();
+        const log = ["first line", "second line"];
+        const identifier = "identifier";
+
+        instance.logs[identifier] = log;
+        await instance.save(identifier);
+        expect(fs.writeFile).toBeCalledTimes(1);
+        expect(fs.writeFile).toHaveBeenCalledWith(savePath, "first line\nsecond line\n");
+    });
+    it("asks the user where to save", async () => {
+        const instance = instanceBuilder();
+        const log = ["first line", "second line"];
+        const identifier = "identifier";
+
+        instance.logs[identifier] = log;
+        await instance.save(identifier);
+        expect(dialog.showSaveDialog).toBeCalledTimes(1);
+    });
+    it("doesn't save when the user cancels", async () => {
+        dialog.showSaveDialog = jest.fn().mockResolvedValue({canceled: true, filePath: "path/to/log"})
+        const instance = instanceBuilder();
+        const log = ["first line", "second line"];
+        const identifier = "identifier";
+        instance.logs[identifier] = log;
+        await instance.save(identifier);
+        expect(fs.writeFile).not.toBeCalled();
+    })
+})
+
+function instanceBuilder() {
+    const environment = {
+        win: "i'm a window",
+        settings: {
+            downloadPath: downloadPath
+        }
+    }
+    return new Logger(environment);
+}