Merge pull request #217818 from hsjobeki/doc/lib-runTests

       traceSeqN 2 { a.b.c = 3; } null

       trace: { a = { b = {…}; }; }

       => null

     Type: traceSeqN :: Int -> a -> b -> b

   */

  traceSeqN = depth: x: y:

    let snip = v: if      isList  v then noQuotes "[…]" v

  # -- TESTING --

  /* Evaluate a set of tests.  A test is an attribute set `{expr,

     expected}`, denoting an expression and its expected result.  The

     result is a list of failed tests, each represented as `{name,

     expected, actual}`, denoting the attribute name of the failing

     test and its expected and actual results.

  /* Evaluates a set of tests.

     A test is an attribute set `{expr, expected}`,

     denoting an expression and its expected result.

     The result is a `list` of __failed tests__, each represented as

     `{name, expected, result}`,

     - expected

       - What was passed as `expected`

     - result

       - The actual `result` of the test

     Used for regression testing of the functions in lib; see

     tests.nix for an example. Only tests having names starting with

     "test" are run.

     tests.nix for more examples.

     Important: Only attributes that start with `test` are executed.

     - If you want to run only a subset of the tests add the attribute `tests = ["testName"];`

    Example:

     Add attr { tests = ["testName"]; } to run these tests only.

     runTests {

       testAndOk = {

         expr = lib.and true false;

         expected = false;

       };

       testAndFail = {

         expr = lib.and true false;

         expected = true;

       };

     }

     ->

     [

       {

         name = "testAndFail";

         expected = true;

         result = false;

       }

     ]

    Type:

      runTests :: {

        tests = [ String ];

        ${testName} :: {

          expr :: a;

          expected :: a;

        };

      }

      ->

      [

        {

          name :: String;

          expected :: a;

          result :: a;

        }

      ]

  */

  runTests =

    # Tests to run