test-repo/tests/predicates-declared/__snapshots__/jsfmt.spec.js.snap

exports[`test function-bind.js 1`] = `
"// @flow

// Sanity checks:
//  - use of bind in a position of a function predicate.
//    (This case should fall through, as method calls
//    are currently not supported.) The original behavior
//    (including \`havoc\`) should be retained.

class C {
  m() {
    return true;
  }
  a: 1;

  n() {
    if(this.m.bind(this)) {
      this.a;
    }
  }
}

declare var m: Function;
const o = { a: 1 };

if (m.bind(o)) {
  o.a;
}


class D {
  m: Function;

  n() {
    if(this.m({})) { }
  }
}

declare var m: Function;
const x = \"\";
if (m.bind(this)(x)) { }
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

// Sanity checks:
//  - use of bind in a position of a function predicate.
//    (This case should fall through, as method calls
//    are currently not supported.) The original behavior
//    (including \`havoc\`) should be retained.

class C {
  m() {
    return true;
  }
  a: 1;

  n() {
    if (this.m.bind(this)) {
      this.a;
    }
  }
}

declare var m: Function;
const o = { a: 1 };

if (m.bind(o)) {
  o.a;
}

class D {
  m: Function;

  n() {
    if (this.m({})) {
    }
  }
}

declare var m: Function;
const x = \"\";
if (m.bind(this)(x)) {
}
"
`;

exports[`test function-union.js 1`] = `
"// @flow

declare function f1(x: mixed): boolean %checks(typeof x === \"string\");
declare function f2(x: mixed): boolean %checks(Array.isArray(x));

declare var cond: boolean;

// Feature check:
function foo(x: number | string | Array<string>): number {

  var f = (cond) ? f1 : f2;

  if (f(x)) {
    return x.length;
  } else {
    return 1;
  }
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

declare function f1(x: mixed): boolean %checks(typeof x === \"string\");
declare function f2(x: mixed): boolean %checks(Array.isArray(x));

declare var cond: boolean;

// Feature check:
function foo(x: number | string | Array<string>): number {
  var f = cond ? f1 : f2;

  if (f(x)) {
    return x.length;
  } else {
    return 1;
  }
}
"
`;

exports[`test is-string-decl.js 1`] = `
"// @flow

declare function is_string(x: mixed): boolean %checks(typeof x === \"string\");
declare function is_number(x: mixed): boolean %checks(typeof x === \"number\");

// Feature check:
function foo(x: string | Array<string>): string {
  if (is_string(x)) {
    // The use of \`is_string\` as a conditional check
    // should guarantee the narrowing of the type of \`x\`
    // to string.
    return x;
  } else {
    // Accordingly the negation of the above check
    // guarantees that \`x\` here is an Array<string>
    return x.join();
  }
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

declare function is_string(x: mixed): boolean %checks(typeof x === \"string\");
declare function is_number(x: mixed): boolean %checks(typeof x === \"number\");

// Feature check:
function foo(x: string | Array<string>): string {
  if (is_string(x)) {
    // The use of \`is_string\` as a conditional check
    // should guarantee the narrowing of the type of \`x\`
    // to string.
    return x;
  } else {
    // Accordingly the negation of the above check
    // guarantees that \`x\` here is an Array<string>
    return x.join();
  }
}
"
`;

exports[`test logical-or.js 1`] = `
"// @flow

// Sanity check:
// - conditional functions do not affect behavior of conditional
//   expressions (e.g. \`||\`)

declare function r(x: string): number;
var s = \'a\';
var n = r(s) || 1;
(n: number);

var x = \"\";
if (x = r(s) || 1) {
  (x: number);
}

declare var dollars: mixed;

function foo(x: mixed) { return 1; }
(foo(dollars) || 0);

(Number(dollars) || 0);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

// Sanity check:
// - conditional functions do not affect behavior of conditional
//   expressions (e.g. \`||\`)

declare function r(x: string): number;
var s = \"a\";
var n = r(s) || 1;
(n: number);

var x = \"\";
if (x = r(s) || 1) {
  (x: number);
}

declare var dollars: mixed;

function foo(x: mixed) {
  return 1;
}
foo(dollars) || 0;

Number(dollars) || 0;
"
`;

exports[`test object-invariant.js 1`] = `
"// @flow

// Sanity check:
// - preserving \`havoc\` semantics

type Meeting = {
  organizer: ?Invitee,
  es: Array<Invitee>
}

type Invitee = {
  fbid: number
}

function f(_this: { m: ?Meeting }): string {
  if (!_this.m) {
    return \"0\";
  }

  if (_this.m.es.some((a) => a.fbid === 0)) {

  }
  return \"3\";
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

// Sanity check:
// - preserving \`havoc\` semantics

type Meeting = { organizer: ?Invitee, es: Array<Invitee> };

type Invitee = { fbid: number };

function f(_this: { m: ?Meeting }): string {
  if (!_this.m) {
    return \"0\";
  }

  if (_this.m.es.some(a => a.fbid === 0)) {
  }
  return \"3\";
}
"
`;

exports[`test orig-string-tag-check.js 1`] = `
"// @flow

// The original first-order case

function foo(x: string | Array<string>): string {
  if (typeof x === \"string\") {
    return x; // [ERROR] x: Array<string> doesn\'t match return type
  }
  else {
    return x.join(); // [ERROR] x: string doesn\'t have .join method
  }
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

// The original first-order case

function foo(x: string | Array<string>): string {
  if (typeof x === \"string\") {
    return x; // [ERROR] x: Array<string> doesn\'t match return type
  } else {
    return x.join(); // [ERROR] x: string doesn\'t have .join method
  }
}
"
`;

exports[`test sanity-fall-through.js 1`] = `
"// @flow

// Sanity check:
// - we should still be getting an error at the second return statement

declare function pred<T>(x: T): boolean;

function foo(s: Array<string>): string {
  if (pred(s)) {
    return \"1\";
  }
  return 1;
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

// Sanity check:
// - we should still be getting an error at the second return statement

declare function pred<T>(x: T): boolean;

function foo(s: Array<string>): string {
  if (pred(s)) {
    return \"1\";
  }
  return 1;
}
"
`;

exports[`test sanity-invalid-calls.js 1`] = `
"// @flow

// Sanity check:
// - invalid calls at predicate positions

declare function pred<T>(x: T): boolean;

function foo(s: Array<string>): string {

  if ((1)(s)) {
    return \"1\";
  }

  if ((pred + 1)(\"s\")) {
    return \"1\";
  }

  return \"1\"
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

// Sanity check:
// - invalid calls at predicate positions

declare function pred<T>(x: T): boolean;

function foo(s: Array<string>): string {
  if (1(s)) {
    return \"1\";
  }

  if ((pred + 1)(\"s\")) {
    return \"1\";
  }

  return \"1\";
}
"
`;

exports[`test sanity-is-string-bug.js 1`] = `
"// @flow

declare function is_string(x: mixed): boolean %checks(typeof x === \"string\");
declare function is_number(x: mixed): boolean %checks(typeof x === \"number\");

// Sanity check:
// - Erroneous logic

function bar(x: string | Array<string>): string {
  if (is_number(x)) {
    return x;
  } else {
    return x.join();    // error: both string and Array<string> can flow to x
  }
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

declare function is_string(x: mixed): boolean %checks(typeof x === \"string\");
declare function is_number(x: mixed): boolean %checks(typeof x === \"number\");

// Sanity check:
// - Erroneous logic
function bar(x: string | Array<string>): string {
  if (is_number(x)) {
    return x;
  } else {
    return x.join(); // error: both string and Array<string> can flow to x
  }
}
"
`;

exports[`test sanity-parameter-mismatch.js 1`] = `
"// @flow

// Sanity check: make sure the parameters are checked as usual

declare function foo(
  input: mixed,
  types: string | Array<string>
): boolean %checks(typeof input === \"string\" || Array.isArray(input));

foo(3, 3);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

// Sanity check: make sure the parameters are checked as usual

declare function foo(
  input: mixed,
  types: string | Array<string>
): boolean %checks(typeof input === \"string\" || Array.isArray(input));

foo(3, 3);
"
`;

exports[`test sanity-pred-with-body.js 1`] = `
"// @flow

// Sanity check:
// - predicate functions cannot have bodies (can only be declarations)

function pred(x: mixed): boolean %checks(typeof x === \"string\") { // error: cannot use pred type here
  return typeof x === \"string\";
}

function foo(x: string | Array<string>): string {
  if (pred(x)) {
    return x;
  }
  return \"1\"
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

// Sanity check:
// - predicate functions cannot have bodies (can only be declarations)

function pred(x: mixed): boolean %checks(typeof x === \"string\") {
  // error: cannot use pred type here
  return typeof x === \"string\";
}

function foo(x: string | Array<string>): string {
  if (pred(x)) {
    return x;
  }
  return \"1\";
}
"
`;

exports[`test sanity-return-type.js 1`] = `
"// @flow

declare function f2(x: mixed): string %checks(Array.isArray(x));
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
// @flow

declare function f2(x: mixed): string %checks(Array.isArray(x));
"
`;