Fast, native, Jest-style test framework

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describe("Example", ({test}) => {
  test("ints", ({expect}) =>
    expect.int(7).toBe(5)
  );
  test("bools", ({expect}) =>
    expect.bool(true).not.toBe(false)
  );
});

Running 1 test suite

 FAIL  Example
  • Example › ints

    expect.int(received).toBe(expected)

    Expected: 3
    Received: 2

       3 ┆ 
       4 ┆ describe("Example", ({test}) => {
       5 ┆   test("ints", ({expect}) => {
       6 ┆     expect.int(1 + 1).toBe(3);
       7 ┆     ();
       8 ┆   });
       9 ┆   test("bools", ({expect}) => {

      Raised by primitive operation at ./tests/ExampleTest.re:6:4
      Called from ./map.ml:291:20
      Called from ./common/CommonCollections.re:171:8


Test Suites: 1 failed, 0 passed, 1 total
Tests:       1 failed, 1 passed, 2 total
Time:        0.002s

A web-influenced polymorphic console API for native Console.log(anything) with runtime printing.

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Console.log(4.6);
Console.log("This is a string");
Console.log(a => a + 1);

4.6
This is a string
closure(2182546092)

Terminal highlighting with support for nesting and style propagation.

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<Pastel bold=true color=Pastel.Yellow>
  "This will be formatted as bold, yellow text"
</Pastel>

This will be formatted as bold, yellow text

Utility for extracting structure from unstructured ocaml compiler errors, and displaying them.

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refmterr dune build -p my-project

# Unformatted Error Output:
# File "myFile.ml", line 2, characters 13-21:
# Error: Unbound type constructor whereAmI


 ERROR  myFile.ml:2 13-21

1 ┆ type asd =
2 ┆   | Hello of whereAmI
3 ┆   | Goodbye

The type whereAmI can't be found.

Utility for displaying snippets of files on the command line.

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FCP.printFile(
  "src/file-context-printer/test/DummyFile.re",
  ((7, 1), (7, 11)),
);

 4 ┆  * This source code is licensed under the ...
 5 ┆  * LICENSE file in the root directory of ...
 6 ┆  */;
 7 ┆ let myFunction = () => print_endline("do something");
 8 ┆ 
 9 ┆ let ex = (arg) => {
10 ┆     if(arg === true) {