mongo/jstests/aggregation/expressions/date_from_string_on_error.js

/**
 * Tests for the $dateFromString expression with the optional 'onError' parameter.
 */
(function() {
"use strict";

load("jstests/aggregation/extras/utils.js");  // For assertErrMsgContains.

const onErrorValue = ISODate("2017-07-04T11:56:02Z");
const coll = db.date_from_string_on_error;
coll.drop();

assert.commandWorked(coll.insert({_id: 0}));

// Test that the 'onError' value is returned when 'dateString' is not a valid date/time.
for (let inputDate of ["July 4th",
                       "12:50:53",
                       "2017",
                       "60.Monday1770/06:59",
                       "Not even close",
                       "July 4th, 10000"]) {
    assert.eq(
        [{_id: 0, date: onErrorValue}],
        coll.aggregate({
                $project: {date: {$dateFromString: {dateString: inputDate, onError: onErrorValue}}}
            })
            .toArray());
}

// Test that the 'onError' value is returned when 'dateString' is not a string.
for (let inputDate of [5, {year: 2018, month: 2, day: 5}, ["2018-02-05"]]) {
    assert.eq(
        [{_id: 0, date: onErrorValue}],
        coll.aggregate({
                $project: {date: {$dateFromString: {dateString: inputDate, onError: onErrorValue}}}
            })
            .toArray());
}

// Test that the 'onError' value is ignored when 'dateString' is nullish.
for (let inputDate of [null, undefined, "$missing"]) {
    assert.eq(
        [{_id: 0, date: null}],
        coll.aggregate({
                $project: {date: {$dateFromString: {dateString: inputDate, onError: onErrorValue}}}
            })
            .toArray());
}

// Test that the 'onError' value is returned for unmatched format strings.
for (let inputFormat of ["%Y", "%Y-%m-%dT%H", "Y-m-d"]) {
    assert.eq(
        [{_id: 0, date: onErrorValue}],
        coll.aggregate({
                $project: {
                    date: {
                        $dateFromString:
                            {dateString: "2018-02-06", format: inputFormat, onError: onErrorValue}
                    }
                }
            })
            .toArray());
}

// Test that null is returned when the 'timezone' or 'format' is nullish, regardless of the
// 'onError' value.
for (let nullishValue of [null, undefined, "$missing"]) {
    assert.eq([{_id: 0, date: null}],
              coll.aggregate({
                      $project: {
                          date: {
                              $dateFromString: {
                                  dateString: "2018-02-06T11:56:02Z",
                                  format: nullishValue,
                                  onError: onErrorValue
                              }
                          }
                      }
                  })
                  .toArray());
    assert.eq([{_id: 0, date: null}],
              coll.aggregate({
                      $project: {
                          date: {
                              $dateFromString: {
                                  dateString: "2018-02-06T11:56:02Z",
                                  timezone: nullishValue,
                                  onError: onErrorValue
                              }
                          }
                      }
                  })
                  .toArray());
}

// Test that onError is returned when the input is not a string and other parameters are
// nullish.
assert.eq(
    [{_id: 0, date: onErrorValue}],
    coll.aggregate({
            $project:
                {date: {$dateFromString: {dateString: 5, format: null, onError: onErrorValue}}}
        })
        .toArray());
assert.eq(
    [{_id: 0, date: onErrorValue}],
    coll.aggregate({
            $project: {
                date:
                    {$dateFromString: {dateString: 5, timezone: "$missing", onError: onErrorValue}}
            }
        })
        .toArray());

// Test that onError is ignored when the input is an invalid string and other parameters are
// nullish.
assert.eq(
    [{_id: 0, date: null}],
    coll.aggregate({
            $project: {
                date: {
                    $dateFromString:
                        {dateString: "Invalid date string", format: null, onError: onErrorValue}
                }
            }
        })
        .toArray());
assert.eq([{_id: 0, date: null}],
          coll.aggregate({
                  $project: {
                      date: {
                          $dateFromString: {
                              dateString: "Invalid date string",
                              timezone: "$missing",
                              onError: onErrorValue
                          }
                      }
                  }
              })
              .toArray());

// Test that 'onError' can be any type, not just an ISODate.
for (let onError of [{}, 5, "Not a date", null, undefined]) {
    assert.eq(
        [{_id: 0, date: onError}],
        coll.aggregate(
                {$project: {date: {$dateFromString: {dateString: "invalid", onError: onError}}}})
            .toArray());
}
// Test that a missing 'onError' value results in no output field when used within a $project
// stage.
assert.eq(
    [{_id: 0}],
    coll.aggregate(
            {$project: {date: {$dateFromString: {dateString: "invalid", onError: "$missing"}}}})
        .toArray());

// Test that 'onError' is ignored when the 'format' is invalid.
assertErrCodeAndErrMsgContains(
    coll,
    [{
        $project:
            {date: {$dateFromString: {dateString: "4/26/1992", format: 5, onError: onErrorValue}}}
    }],
    40684,
    "$dateFromString requires that 'format' be a string");

assertErrCodeAndErrMsgContains(
    coll,
    [{
        $project: {
            date: {$dateFromString: {dateString: "4/26/1992", format: "%n", onError: onErrorValue}}
        }
    }],
    18536,
    "Invalid format character '%n' in format string");
})();