railsish v0.9.0

import { strict: assert } from "assert";
import { isPresent, isBlank } from "railsish";

// It treats empty or invalid values as blank...
assert(isBlank([]), "an empty array is blank");
assert(isBlank({}), "an empty object is blank");
assert(isBlank(new Date("2020-03-32")), "an invalid date is blank");
assert(isBlank(NaN), "NaN is blank");
assert(isBlank("\n\t  "), "a string containing only whitespace is blank");

// But there's a special case: 0 is present!
assert(isPresent(0), "0 is present");

import { strict: assert } from "assert";
import { getPresent } from "railsish";

assert.equal(getPresent({ foo: { bar: { baz: null } } }, "foo.bar.baz", "quux"), "quux", "it will return a default value");

import { strict: assert } from "assert";
import { getPresentNumber, getPresentString } from "railsish";

assert.equal(getPresentNumber({ foo: "-3.14" }, "foo"), -3.14, "fetching a numeric string will cast it");
assert.equal(getPresentString({ foo: "\t" }, "foo", "default"), "default", "whitespace-only strings are not present");

import { booleanize } from "railsish";

booleanize(0) === false
booleanize("0") == false
// an empty object
booleanize({}) === false
// an empty array
booleanize([]) === false
booleanize(new Int8Array()) === false
// an empty string
booleanize("") === false
// a string that's only whitespace
booleanize("    ") === false
// special string handling: the following are case-insensitive
booleanize("F") === false
booleanize("n") === false
booleanize("no") === false
booleanize("nil") === false
booleanize("NULL") === false
booleanize("FALSE") === false

import { strict: assert } from "assert";
import { getBoolean } from "railsish";

assert.fail(getBoolean({ foo: [] }, "foo"), "it will booleanize the value at a given path");

booleanize(0) === false
booleanize("0") == false
// an empty object
booleanize({}) === false
// an empty array
booleanize([]) === false
booleanize(new Int8Array()) === false
// an empty string
booleanize("") === false
// a string that's only whitespace
booleanize("    ") === false
// special string handling: the following are case-insensitive
booleanize("F") === false
booleanize("n") === false
booleanize("no") === false
booleanize("nil") === false
booleanize("NULL") === false
booleanize("FALSE") === false

import { getPresentArray }
const response = {
  foo: {
    bar: {
      baz: {
        quux: []
      }
    }
  }
};

// instead of this:
function extractDeepValue(value) {
  if (value && value.foo) {
    if (value.foo.bar) {
      if (value.foo.bar.baz) {
        if (Array.isArray(value.foo.bar.baz.quux) && value.foo.bar.baz.quux.length > 0) {
          return value;
        }
      }
    }
  }

  return ["default"];
};

extractDeepValue(response, ["default"]);

// you can just:
getPresentArray(response, "foo.bar.baz.quux", ["default"]);

import { getPresentArray } from "railsish";

const NO_TAGS_SELECTED = Symbol("NO_TAGS");

const getSelectedTags = (config) => getPresentArray(config, "user.selected.tags", NO_TAGS_SELECTED);

// A contrived express handler
export async function renderSelectedTags(req, res) {
  const tags = getSelectedTags(req.user.config);

  if (tags === NO_TAGS_SELECTED) {
    // take the user to a 
    return res.json({
      error: "User needs to select tags",
      code: "SELECT_TAGS_FIRST"
    }).status(400);
  }

  const tagResponse = await myDB.getTags(tags);

  res.json(tagResponse);
}

// It'll booleanize a deeply-nested value
getBoolean({ foo: { bar: [] } }, "foo.bar") === false;

getPresentString({ foo: "\t" }, "foo", "default") === "default";

isPresentObject({}) === false
isPresentObject({ foo: "bar" }) === true
isPresentObject([]) === false
isPresentObject(new Foo()) === false
isPresentObject(Object.create(null)) === false

isBlankObject({}) === true
isBlankObject({ foo: "bar" }) === false
isBlankObject([]) === false
isBlankObject(new Foo()) === false
isBlankObject(Object.create(null)) === false

import { install as installRailsishMatchers } from "railsish/jest-matchers"

installRailsishMatchers(expect)

describe("some tests", () => {
  it("returns a present response", () => {
    expect(myLibrary.doSomething()).toBePresent();
  });

  it("returns something blank", () => {
   expect(anonymousRequest.getCurrentUser()).toBeBlank();
  });

  it("implements foo", () => {
    expect({ foo: () => "bar" }).toRespondTo("foo");
  });
});

// in a file called by "setupFilesAfterEnv":
import { install } from "railsish/jest-matchers"

install(expect);

expect(0).toBePresent();
expect([]).not.toBePresent();
expect(false).not.toBePresent();
expect("some string").toBePresent();
expect({}).not.toBePresent();
expect({ foo: "bar" }).toBePresent();
expect

expect(0).not.toBeBlank();
expect([]).toBeBlank();
expect({}).toBeBlank();
expect(NaN).toBeBlank();
expect(Infinity).not.toBeBlank();
expect("\t\n\t").toBeBlank();

expect("some text").toBooleanizeAs(true);
expect([]).toBooleanizeAs(false);

expect("some text").toBooleanizeTrue();
expect([]).not.toBooleanizeTrue();

expect("some text").not.toBooleanizeFalse();
expect([]).toBooleanizeFalse();

expect(new Date()).toRespondTo("toISOString");

expect({ foo: { bar: { baz: () => "quux" } } }).toRespondToPath("foo.bar.baz");