vore-rpg/src/scripting/NomScript.test.ts

import { parse, SyntaxError } from "./NomScript.peggy";

describe("parse", () => {
  describe("ScriptFile", () => {
    test("works with an empty input", () => {
      expect(() => parse("", {grammarSource: "testData", start: "ScriptFile"})).not.toThrow()
    });
    test("works with empty lines", () => {
      expect(() => parse("\n\n\n\n\n", {grammarSource: "testData", start: "ScriptFile"})).not.toThrow()
    });
    test("works with lines filled only with whitespace", () => {
      expect(() => parse("\n\n       \n\t\t    \t\n\n", {grammarSource: "testData", start: "ScriptFile"})).not.toThrow()
    });
    test("works with lines filled only with comments", () => {
      expect(() => parse("\n\n    /*      */ \n// test \n /*     */\n", {grammarSource: "testData", start: "ScriptFile"})).not.toThrow()
    });
    test("throws SyntaxError for invalid text", () => {
      expect(() => parse("!! invalid !!", {grammarSource: "testData", start: "ScriptFile"})).toThrow(SyntaxError)
    });
  })
});

describe("SyntaxError", () => {
  describe("constructor", () => {
    test("populates the members accordingly", () => {
      const location = {
        source: "source",
        start: {
          offset: 0,
          line: 1,
          column: 1,
        },
        end: {
          offset: 7,
          line: 1,
          column: 8,
        },
      };
      const err = new SyntaxError("message", ["expected"], "found", location);

      expect(err.name).toEqual("SyntaxError");
      expect(err.message).toEqual("message");
      expect(err.expected).toEqual(["expected"]);
      expect(err.found).toEqual("found");
      expect(err.location).toEqual(location);
    });
  });
  describe("format", () => {
    test("displays a pretty error message for the failure", () => {
      const location = {
        source: "source",
        start: {
          offset: 0,
          line: 1,
          column: 1,
        },
        end: {
          offset: 7,
          line: 1,
          column: 8,
        },
      };
      const err = new SyntaxError(
        "message",
        ["valid", "cool"],
        "errored",
        location
      );
      const result = err.format([
        { source: "source", text: "errored text" },
        { source: "source2", text: "irrelevant" },
      ]);

      expect(result).toMatchInlineSnapshot(`
        "Error: message
         --> source:1:1
          |
        1 | errored text
          | ^^^^^^^"
      `);
    });
  });
});