tm-landing/lib/__tests__/apiErrorHandler.test.ts

import { AxiosError } from "axios";
import { handleApiError, parseApiError } from "../apiErrorHandler";

describe("API Error Handler", () => {
  describe("parseApiError", () => {
    it("should return default message for non-Error objects", () => {
      const result = parseApiError("string error");
      expect(result.generalMessage).toBe("Something went wrong. Please try again.");
      expect(result.fieldErrors).toEqual({});
    });

    it("should handle network errors (no response)", () => {
      const error = new Error("Network Error") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = undefined;

      const result = parseApiError(error);
      expect(result.generalMessage).toContain("Unable to connect");
    });

    it("should parse 400 errors with field-level errors", () => {
      const error = new Error("Bad Request") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 400,
        data: {
          errors: {
            email: "Invalid email format",
            full_name: ["Name is too short", "Name contains invalid characters"],
          },
        },
        statusText: "Bad Request",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.generalMessage).toContain("highlighted fields");
      expect(result.fieldErrors.email).toMatch(/email/i);
      expect(result.fieldErrors.full_name).toMatch(/name|short|character/i);
    });

    it("should map message-only 400 responses without exposing raw server text", () => {
      const error = new Error("Bad Request") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 400,
        data: {
          message: "Custom validation error message",
        },
        statusText: "Bad Request",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.generalMessage).not.toContain("Custom validation");
      expect(result.generalMessage.length).toBeGreaterThan(10);
    });

    it("should parse nested error object with field errors", () => {
      const error = new Error("Bad Request") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 400,
        data: {
          error: {
            code: "validation_failed",
            errors: { work_email: "invalid_email" },
          },
        },
        statusText: "Bad Request",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.fieldErrors.work_email).toMatch(/email/i);
    });

    it("should parse FastAPI-style detail arrays", () => {
      const error = new Error("Unprocessable") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 422,
        data: {
          detail: [
            { loc: ["body", "phone_number"], msg: "value is not a valid phone" },
          ],
        },
        statusText: "Unprocessable Entity",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.fieldErrors.phone_number).toMatch(/phone/i);
    });

    it("should handle 401 unauthorized errors", () => {
      const error = new Error("Unauthorized") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 401,
        data: {},
        statusText: "Unauthorized",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.generalMessage).toMatch(/Authentication|Sign in/i);
    });

    it("should handle 422 unprocessable entity errors", () => {
      const error = new Error("Unprocessable Entity") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 422,
        data: {
          errors: {
            phone: "invalid_phone",
          },
        },
        statusText: "Unprocessable Entity",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.generalMessage).toContain("highlighted fields");
      expect(result.fieldErrors.phone).toContain("phone number");
    });

    it("should handle 429 rate limit errors", () => {
      const error = new Error("Too Many Requests") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 429,
        data: {},
        statusText: "Too Many Requests",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.generalMessage).toMatch(/many|wait/i);
    });

    it("should handle 500 server errors", () => {
      const error = new Error("Internal Server Error") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 500,
        data: {},
        statusText: "Internal Server Error",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.generalMessage).toMatch(/server|try again/i);
    });

    it("should give a client-safe message for unlisted 4xx statuses with a body", () => {
      const error = new Error("Nope") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 418,
        data: { message: "I'm a teapot" },
        statusText: "I'm a teapot",
        headers: {},
        config: {} as any,
      };

      const result = parseApiError(error);
      expect(result.generalMessage).not.toContain("teapot");
      expect(result.generalMessage.length).toBeGreaterThan(5);
    });
  });

  describe("handleApiError", () => {
    it("should call setError for each field error", () => {
      const mockSetError = jest.fn();
      const mockShowToast = jest.fn();

      const error = new Error("Bad Request") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 400,
        data: {
          errors: {
            email: "Invalid email",
            phone: "Invalid phone",
          },
        },
        statusText: "Bad Request",
        headers: {},
        config: {} as any,
      };

      handleApiError(error, mockSetError, mockShowToast, ["email", "phone"]);

      expect(mockSetError).toHaveBeenCalledTimes(2);
      expect(mockSetError).toHaveBeenCalledWith(
        "email",
        expect.objectContaining({ type: "server", message: expect.any(String) })
      );
      expect(mockSetError).toHaveBeenCalledWith(
        "phone",
        expect.objectContaining({ type: "server", message: expect.any(String) })
      );
      expect(mockShowToast).toHaveBeenCalledWith(expect.stringContaining("highlighted fields"));
    });

    it("should only set errors for fields in formFields list", () => {
      const mockSetError = jest.fn();
      const mockShowToast = jest.fn();

      const error = new Error("Bad Request") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 400,
        data: {
          errors: {
            email: "Invalid email",
            unknown_field: "Unknown error",
          },
        },
        statusText: "Bad Request",
        headers: {},
        config: {} as any,
      };

      handleApiError(error, mockSetError, mockShowToast, ["email"]);

      expect(mockSetError).toHaveBeenCalledTimes(1);
      expect(mockSetError).toHaveBeenCalledWith(
        "email",
        expect.objectContaining({ type: "server" })
      );
    });

    it("should show general message when no field errors", () => {
      const mockSetError = jest.fn();
      const mockShowToast = jest.fn();

      const error = new Error("Internal Server Error") as AxiosError;
      error.isAxiosError = true;
      (error as AxiosError).response = {
        status: 500,
        data: {},
        statusText: "Internal Server Error",
        headers: {},
        config: {} as any,
      };

      handleApiError(error, mockSetError, mockShowToast, ["email"]);

      expect(mockSetError).not.toHaveBeenCalled();
      expect(mockShowToast).toHaveBeenCalledWith(expect.stringMatching(/server|try again/i));
    });
  });
});