mongo/jstests/aggregation/expressions/arrayToObject.js

// Tests for $arrayToObject aggregation expression.
import "jstests/libs/query/sbe_assert_error_override.js";

import {assertErrorCode} from "jstests/aggregation/extras/utils.js";

let coll = db.array_to_object_expr;
coll.drop();

// Write one document so that the aggregations which use $const produce a result.
assert.commandWorked(coll.insert({_id: "sentinel", a: 1}));

/*
 * Check that the collapsed, object form of 'expanded' (which is computed using $arrayToObject)
 * matches our expectation.
 */
function assertCollapsed(expanded, expectedCollapsed) {
    assert(coll.drop());
    assert.commandWorked(coll.insert({expanded: expanded}));
    const result = coll.aggregate([{$project: {collapsed: {$arrayToObject: "$expanded"}}}]).toArray()[0].collapsed;
    assert.eq(result, expectedCollapsed);
}

// assert with case-insensitive collation
function assertCollapsedWithCollation(expanded, expectedCollapsed) {
    assert(coll.drop());
    assert.commandWorked(coll.insert({expanded: expanded}));
    const result = coll
        .aggregate([{$project: {collapsed: {$arrayToObject: "$expanded"}}}], {
            collation: {locale: "en_US", strength: 2},
        })
        .toArray()[0].collapsed;
    assert.eq(result, expectedCollapsed);
}

/*
 * Check that $arrayToObject on the given value produces the expected error.
 */
function assertPipelineErrors(expanded, errorCode) {
    assert(coll.drop());
    assert.commandWorked(coll.insert({expanded: expanded}));
    assertErrorCode(coll, [{$project: {collapsed: {$arrayToObject: "$expanded"}}}], errorCode);
}

// $arrayToObject correctly converts a key-value pairs to an object.
assertCollapsed(
    [
        ["price", 24],
        ["item", "apple"],
    ],
    {"price": 24, "item": "apple"},
);
assertCollapsed(
    [
        {"k": "price", "v": 24},
        {"k": "item", "v": "apple"},
    ],
    {"price": 24, "item": "apple"},
);
// If duplicate field names are in the array, $arrayToObject should use value from the last one.
assertCollapsed(
    [
        {"k": "price", "v": 24},
        {"k": "price", "v": 100},
    ],
    {"price": 100},
);
assertCollapsed(
    [
        ["price", 24],
        ["price", 100],
    ],
    {"price": 100},
);

// Test with collation
assertCollapsedWithCollation(
    [
        {"k": "price", "v": 24},
        {"k": "PRICE", "v": 100},
    ],
    {"price": 24, "PRICE": 100},
);
assertCollapsedWithCollation(
    [
        ["price", 24],
        ["PRICE", 100],
    ],
    {"price": 24, "PRICE": 100},
);

assertCollapsed(
    [
        ["price", 24],
        ["item", "apple"],
    ],
    {"price": 24, "item": "apple"},
);
assertCollapsed([], {});

assertCollapsed(null, null);
assertCollapsed(undefined, null);
assertCollapsed([{"k": "price", "v": null}], {"price": null});
assertCollapsed([{"k": "price", "v": undefined}], {"price": undefined});
// Need to manually check the case where 'expanded' is not in the document.
coll.drop();
assert.commandWorked(coll.insert({_id: "missing-expanded-field"}));
const result = coll.aggregate([{$project: {collapsed: {$arrayToObject: "$expanded"}}}]).toArray();
assert.eq(result, [{_id: "missing-expanded-field", collapsed: null}]);

assertPipelineErrors([{"k": "price", "v": 24}, ["item", "apple"]], 40391);
assertPipelineErrors([["item", "apple"], {"k": "price", "v": 24}], 40396);
assertPipelineErrors("string", 40386);
assertPipelineErrors(ObjectId(), 40386);
assertPipelineErrors(NumberLong(0), 40386);
assertPipelineErrors([0], 40398);
assertPipelineErrors([["missing_value"]], 40397);
assertPipelineErrors([[321, 12]], 40395);
assertPipelineErrors([["key", "value", "offset"]], 40397);
assertPipelineErrors({y: []}, 40386);
assertPipelineErrors([{y: "x", x: "y"}], 40393);
assertPipelineErrors([{k: "missing"}], 40392);
assertPipelineErrors([{k: 24, v: "string"}], 40394);
assertPipelineErrors([{k: null, v: "nullKey"}], 40394);
assertPipelineErrors([{k: undefined, v: "undefinedKey"}], 40394);
assertPipelineErrors([{y: "ignored", k: "item", v: "pear"}], 40392);
assertPipelineErrors(NaN, 40386);

// Check that $arrayToObject produces an error when the key contains a null byte.
assertPipelineErrors([["a\0b", "abra cadabra"]], 4940400);
assertPipelineErrors([{k: "a\0b", v: "blah"}], 4940401);

assertErrorCode(coll, [{$replaceWith: {$arrayToObject: {$literal: [["a\0b", "abra cadabra"]]}}}], 4940400);
assertErrorCode(coll, [{$replaceWith: {$arrayToObject: {$literal: [{k: "a\0b", v: "blah"}]}}}], 4940401);
assertErrorCode(
    coll,
    [{$replaceWith: {$arrayToObject: {$literal: [["a\0b", "abra cadabra"]]}}}, {$out: "output"}],
    4940400,
);
assertErrorCode(
    coll,
    [{$replaceWith: {$arrayToObject: {$literal: [{k: "a\0b", v: "blah"}]}}}, {$out: "output"}],
    4940401,
);