diff options
Diffstat (limited to 'js/src')
-rw-r--r-- | js/src/builtin/Object.cpp | 1 | ||||
-rw-r--r-- | js/src/builtin/Object.js | 18 |
2 files changed, 19 insertions, 0 deletions
diff --git a/js/src/builtin/Object.cpp b/js/src/builtin/Object.cpp index bfcc8d20e..d3001b69e 100644 --- a/js/src/builtin/Object.cpp +++ b/js/src/builtin/Object.cpp @@ -1239,6 +1239,7 @@ static const JSFunctionSpec object_static_methods[] = { JS_FN("isFrozen", obj_isFrozen, 1, 0), JS_FN("seal", obj_seal, 1, 0), JS_FN("isSealed", obj_isSealed, 1, 0), + JS_SELF_HOSTED_FN("fromEntries", "ObjectFromEntries", 1, 0), JS_FS_END }; diff --git a/js/src/builtin/Object.js b/js/src/builtin/Object.js index 9ed1be0e1..c4739037e 100644 --- a/js/src/builtin/Object.js +++ b/js/src/builtin/Object.js @@ -202,3 +202,21 @@ function ObjectLookupGetter(name) { // Step 3.d. (implicit) } + +// Stage 4 draft 2020-09-06 https://tc39.github.io/proposal-object-from-entries/ +// Object.fromEntries (iterable) +function ObjectFromEntries(iter) { + // We omit the usual step number comments here because they don't help. + // This implementation inlines AddEntriesFromIterator and + // CreateDataPropertyOnObject, so it looks more like the polyfill + // than the step-by-step spec algorithm. + const obj = {}; + + for (const pair of allowContentIter(iter)) { + if (!IsObject(pair)) + ThrowTypeError(JSMSG_INVALID_MAP_ITERABLE, "Object.fromEntries"); + _DefineDataProperty(obj, pair[0], pair[1]); + } + + return obj; +} |