🧪 [testing improvement] Add missing tests for editor.ts

- Added `src/ui/editor.test.ts` to provide test coverage for `SumEditor` core UI wrapping methods.
- Avoided jsdom reliance by mocking out CodeMirror and browser environment globals to satisfy memory guidelines while still covering the required behaviors.

Co-authored-by: Horizontal42 <75383519+Horizontal42@users.noreply.github.com>

src/ui/editor.test.ts

@@ -0,0 +1,172 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+
+// Mocking SumEditor completely because CodeMirror UI interactions require a full DOM
+// and this project prohibits jsdom/happy-dom.
+
+// A minimal mock for EditorView so we don't load the real one
+vi.mock("@codemirror/view", async (importOriginal) => {
+  const actual: any = await importOriginal();
+  const mockView = class MockEditorView {
+    state = {
+      doc: {
+        toString: () => "mock text",
+        lines: 2,
+        line: (n: number) => ({ text: `line ${n}`, from: (n-1)*10, to: n*10 }),
+        lineAt: () => ({ number: 1, from: 0, to: 10 }),
+        length: 20,
+        iterLines: () => ({ next: vi.fn().mockReturnValue({ done: true }) })
+      },
+      selection: { main: { empty: true, from: 0, to: 0 } },
+      field: vi.fn().mockReturnValue([])
+    };
+    dom = { addEventListener: vi.fn() };
+    scrollDOM = { addEventListener: vi.fn() };
+    documentTop = 0;
+    dispatch = vi.fn();
+    focus = vi.fn();
+    lineBlockAt = vi.fn().mockReturnValue({ top: 0 });
+    constructor(config: any) {
+      if (config.state?.doc !== undefined && typeof config.state.doc !== 'string') {
+         this.state = config.state;
+      }
+    }
+  };
+  (mockView as any).decorations = { from: vi.fn() };
+  (mockView as any).theme = vi.fn();
+  (mockView as any).updateListener = { of: vi.fn() };
+  (mockView as any).lineWrapping = {};
+
+  return {
+    ...actual,
+    EditorView: mockView,
+    ViewPlugin: { fromClass: vi.fn() },
+    Decoration: { mark: vi.fn(), line: vi.fn(), none: [] },
+    drawSelection: vi.fn(),
+  };
+});
+
+vi.mock("@codemirror/state", async (importOriginal) => {
+  const actual: any = await importOriginal();
+  return {
+    ...actual,
+    EditorState: { create: vi.fn((config) => config) },
+    StateEffect: { define: vi.fn(() => ({ of: vi.fn() })) },
+    StateField: { define: vi.fn(() => ({})) },
+    RangeSetBuilder: class {
+      add = vi.fn();
+      finish = vi.fn().mockReturnValue([]);
+    }
+  };
+});
+
+vi.mock("@codemirror/commands", () => ({
+  defaultKeymap: [],
+  history: vi.fn(),
+  historyKeymap: [],
+}));
+
+vi.mock("@codemirror/autocomplete", () => ({
+  autocompletion: vi.fn(),
+  acceptCompletion: vi.fn(),
+}));
+
+import { SumEditor } from "./editor";
+
+describe("SumEditor", () => {
+  let mockParent: any;
+  let mockResultsEl: any;
+  let mockEngine: any;
+  let mockCb: any;
+  let evaluateDoc: any;
+
+  beforeEach(() => {
+    mockParent = { appendChild: vi.fn() };
+    mockResultsEl = {
+      getBoundingClientRect: vi.fn().mockReturnValue({ top: 0, height: 100 }),
+      clientHeight: 100,
+      addEventListener: vi.fn(),
+      replaceChildren: vi.fn(),
+    };
+
+    mockEngine = { completions: vi.fn().mockReturnValue([]) };
+    mockCb = {
+      onChange: vi.fn(),
+      onCopy: vi.fn(),
+      onResults: vi.fn(),
+      onSelection: vi.fn(),
+    };
+    evaluateDoc = vi.fn().mockReturnValue([]);
+
+    vi.stubGlobal("document", {
+      createElement: vi.fn(() => ({
+        className: "",
+        style: {},
+        textContent: "",
+        dataset: {},
+        title: "",
+      })),
+      createDocumentFragment: vi.fn(() => ({
+        appendChild: vi.fn(),
+      })),
+    });
+    vi.stubGlobal("requestAnimationFrame", (cb: any) => cb());
+    vi.stubGlobal("window", { requestAnimationFrame: (cb: any) => cb() });
+  });
+
+  afterEach(() => {
+    vi.unstubAllGlobals();
+    vi.clearAllMocks();
+  });
+
+  it("can be instantiated", () => {
+    const editor = new SumEditor(mockParent, mockResultsEl, mockEngine, mockCb, evaluateDoc, "test");
+    expect(editor).toBeDefined();
+    expect(evaluateDoc).toHaveBeenCalledWith("test");
+  });
+
+  it("setText updates the editor", () => {
+    const editor = new SumEditor(mockParent, mockResultsEl, mockEngine, mockCb, evaluateDoc, "test");
+    editor.setText("new test");
+    expect(editor.view.dispatch).toHaveBeenCalledWith(expect.objectContaining({
+      changes: expect.objectContaining({ insert: "new test" })
+    }));
+  });
+
+  it("getText retrieves the current document text", () => {
+    const editor = new SumEditor(mockParent, mockResultsEl, mockEngine, mockCb, evaluateDoc, "test");
+    expect(editor.getText()).toBe("mock text"); // From our mock
+  });
+
+  it("refresh re-evaluates the current text", () => {
+    const editor = new SumEditor(mockParent, mockResultsEl, mockEngine, mockCb, evaluateDoc, "test");
+    evaluateDoc.mockClear();
+    editor.refresh();
+    expect(evaluateDoc).toHaveBeenCalledWith("mock text");
+  });
+
+  it("focus sets focus on the view", () => {
+    const editor = new SumEditor(mockParent, mockResultsEl, mockEngine, mockCb, evaluateDoc, "test");
+    editor.focus();
+    expect(editor.view.focus).toHaveBeenCalled();
+  });
+
+  it("goToLine scrolls to the correct line", () => {
+    const editor = new SumEditor(mockParent, mockResultsEl, mockEngine, mockCb, evaluateDoc, "test");
+    editor.goToLine(2);
+    expect(editor.view.dispatch).toHaveBeenCalledWith(expect.objectContaining({
+      selection: expect.anything(),
+      scrollIntoView: true
+    }));
+    expect(editor.view.focus).toHaveBeenCalled();
+  });
+
+  it("getSheetWithResults appends evaluated results to lines", () => {
+    const mockResults = [{ text: "10" }, { text: "20" }];
+    evaluateDoc.mockReturnValue(mockResults);
+    const editor = new SumEditor(mockParent, mockResultsEl, mockEngine, mockCb, evaluateDoc, "test");
+
+    // We mocked EditorView to return doc.lines = 2 and doc.line(n) = `line ${n}`
+    const result = editor.getSheetWithResults();
+    expect(result).toBe("line 1 = 10\nline 2 = 20");
+  });
+});

test_plan.ts

@@ -0,0 +1,10 @@
+// Just to check what fails in node with codemirror
+import { EditorState } from "@codemirror/state";
+import { EditorView } from "@codemirror/view";
+
+try {
+  const state = EditorState.create({doc: "hello"});
+  console.log("State OK");
+} catch(e) {
+  console.log("State Error", e);
+}