babel/eslint/babel-eslint-parser/test/babel-eslint.js

var babelEslint = require("..");
var espree      = require("espree");
var util        = require("util");

// Checks if the source ast implements the target ast. Ignores extra keys on source ast
function assertImplementsAST(target, source, path) {
  if (!path) {
    path = [];
  }

  function error(text) {
    var err = new Error("At " + path.join(".") + ": " + text + ":");
    err.depth = path.length + 1;
    throw err;
  }

  var typeA = target === null ? "null" : typeof target;
  var typeB = source === null ? "null" : typeof source;
  if (typeA !== typeB) {
    error("have different types (" + typeA + " !== " + typeB + ")");
  } else if (typeA === "object") {
    var keysTarget = Object.keys(target);
    for (var i in keysTarget) {
      var key = keysTarget[i];
      path.push(key);
      assertImplementsAST(target[key], source[key], path);
      path.pop();
    }
  } else if (target !== source) {
    error("are different (" + JSON.stringify(target) + " !== " + JSON.stringify(source) + ")");
  }
}

function parseAndAssertSame(code) {
  var esAST = espree.parse(code, {
    env: {
      "es6": true,
      "node": true
    },
    ecmaFeatures: {
      blockBindings: true,
      templateStrings: true,
      modules: true,
      classes: true,
      jsx: true
    },
    tokens: true,
    loc: true,
    range: true,
    comment: true,
    attachComment: true
  });
  var acornAST = babelEslint.parse(code);
  try {
    assertImplementsAST(esAST, acornAST);
  } catch(err) {
    err.message +=
      "\nespree:\n" +
      util.inspect(esAST, {depth: err.depth, colors: true}) +
      "\nbabel-eslint:\n" +
      util.inspect(acornAST, {depth: err.depth, colors: true});
    throw err;
  }
}

describe("acorn-to-esprima", function () {
  describe("templates", function () {
    it("empty template string", function () {
      parseAndAssertSame("``");
    });

    it("template string", function () {
      parseAndAssertSame("`test`");
    });

    it("template string using $", function () {
      parseAndAssertSame("`$`");
    });

    it("template string with expression", function () {
      parseAndAssertSame("`${a}`");
    });

    it("template string with multiple expressions", function () {
      parseAndAssertSame("`${a}${b}${c}`");
    });

    it("template string with expression and strings", function () {
      parseAndAssertSame("`a${a}a`");
    });

    it("template string with binary expression", function () {
      parseAndAssertSame("`a${a + b}a`");
    });

    it("tagged template", function () {
      parseAndAssertSame("jsx`<Button>Click</Button>`");
    });

    it("tagged template with expression", function () {
      parseAndAssertSame("jsx`<Button>Hi ${name}</Button>`");
    });

    it("tagged template with new operator", function () {
      parseAndAssertSame("new raw`42`");
    });

    it("template with nested function/object", function () {
      parseAndAssertSame("`outer${{x: {y: 10}}}bar${`nested${function(){return 1;}}endnest`}end`");
    });

    it("template with braces inside and outside of template string #96", function () {
      parseAndAssertSame("if (a) { var target = `{}a:${webpackPort}{}}}}`; } else { app.use(); }");
    });

    it("template also with braces #96", function () {
      parseAndAssertSame(
        "export default function f1() {" +
          "function f2(foo) {" +
            "const bar = 3;" +
            "return `${foo} ${bar}`;" +
          "}" +
          "return f2;" +
        "}"
      );
    });
  });

  it("simple expression", function () {
    parseAndAssertSame("a = 1");
  });

  it("class declaration", function () {
    parseAndAssertSame("class Foo {}");
  });

  it("class expression", function () {
    parseAndAssertSame("var a = class Foo {}");
  });

  it("jsx expression", function () {
    parseAndAssertSame("<App />");
  });

  it("jsx expression with 'this' as identifier", function () {
    parseAndAssertSame("<this />");
  });

  it("jsx expression with a dynamic attribute", function () {
    parseAndAssertSame("<App foo={bar} />");
  });

  it("jsx expression with a member expression as identifier", function () {
    parseAndAssertSame("<foo.bar />");
  });

  it("default import", function () {
    parseAndAssertSame('import foo from "foo";');
  });

  it("import specifier", function () {
    parseAndAssertSame('import { foo } from "foo";');
  });

  it("import specifier with name", function () {
    parseAndAssertSame('import { foo as bar } from "foo";');
  });

  it("import bare", function () {
    parseAndAssertSame('import "foo";');
  });

  it("export default class declaration", function () {
    parseAndAssertSame("export default class Foo {}");
  });

  it("export default class expression", function () {
    parseAndAssertSame("export default class {}");
  });

  it("export default function declaration", function () {
    parseAndAssertSame("export default function Foo() {}");
  });

  it("export default function expression", function () {
    parseAndAssertSame("export default function () {}");
  });

  it("export all", function () {
    parseAndAssertSame('export * from "foo";');
  });

  it("export named", function () {
    parseAndAssertSame("export { foo };");
  });

  it("export named alias", function () {
    parseAndAssertSame("export { foo as bar };");
  });

  it("empty program with line comment", function () {
    parseAndAssertSame("// single comment");
  });

  it("empty program with block comment", function () {
    parseAndAssertSame("  /* multiline\n * comment\n*/");
  });

  it("line comments", function () {
    parseAndAssertSame([
      "  // single comment",
      "var foo = 15; // comment next to statement",
      "// second comment after statement"
    ].join("\n"));
  });

  it("block comments", function () {
    parseAndAssertSame([
      "  /* single comment */ ",
      "var foo = 15; /* comment next to statement */",
      "/*",
      " * multiline",
      " * comment",
      " */"
    ].join("\n"));
  });

  it("null", function () {
    parseAndAssertSame("null");
  });

  it("boolean", function () {
    parseAndAssertSame("if (true) {} else if (false) {}");
  });

  it("regexp", function () {
    parseAndAssertSame("/affix-top|affix-bottom|affix|[a-z]/");
  });

  it("regexp in a template string", function () {
    parseAndAssertSame("`${/\\d/.exec(\"1\")[0]}`");
  });
});