Test removal of default locale fallback in Intl.Locale.p.getCollations

test/intl402/Locale/prototype/getCollations/collation-keyword.js

@@ -0,0 +1,40 @@
+// Copyright 2026 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-Intl.Locale.prototype.getCollations
+description: >
+  u-co extension keyword and collation option override language lookup
+info: |
+  CollationsOfLocale ( loc )
+
+  1. If _loc_.[[Collation]] is not *undefined*, then
+    a. Return CreateArrayFromList(« _loc_.[[Collation]] »).
+features: [Intl.Locale,Intl.Locale-info]
+locale: [en, de, zh]
+---*/
+
+var testCases = [
+  ["en", "phonebk"],
+  ["de", "phonebk"],
+  ["zh", "stroke"],
+  ["und", "pinyin"],
+  ["und", "emoji"]
+];
+
+for (var i = 0; i < testCases.length; i++) {
+  var baseName = testCases[i][0];
+  var collation = testCases[i][1];
+  var fullTag = baseName + "-u-co-" + collation;
+
+  assert.compareArray(
+    new Intl.Locale(fullTag).getCollations(),
+    [collation],
+    "getCollations() for " + fullTag + " returns only " + collation
+  );
+  assert.compareArray(
+    new Intl.Locale(baseName, { collation: collation }).getCollations(),
+    [collation],
+    "getCollations() for " + baseName + " with { collation: " + collation + " } returns only " + collation
+  );
+}

test/intl402/Locale/prototype/getCollations/output-array-sorted.js

@@ -0,0 +1,28 @@
+// Copyright 2026 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-Intl.Locale.prototype.getCollations
+description: The returned array is sorted in lexicographic code unit order
+info: |
+  CollationsOfLocale ( loc )
+
+  5. Let _sorted_ be a copy of _list_, sorted according to lexicographic code
+     unit order.
+  6. Return CreateArrayFromList(_sorted_).
+features: [Intl.Locale,Intl.Locale-info]
+locale: [ar, de, en, ja, ko, sv, tr, zh]
+---*/
+
+var tags = ["ar", "de", "en", "ja", "ko", "sv", "tr", "zh"];
+
+for (var i = 0; i < tags.length; i++) {
+  var tag = tags[i];
+  var collations = new Intl.Locale(tag).getCollations();
+  var sortedCollations = [].concat(new Intl.Locale(tag).getCollations()).sort();
+  assert.compareArray(
+    collations,
+    sortedCollations,
+    "getCollations() for " + tag + " should be sorted in lexicographic code unit order"
+  );
+}

test/intl402/Locale/prototype/getCollations/output-array-values.js

@@ -3,23 +3,27 @@
 
 /*---
 esid: sec-intl.locale.prototype.collations
-description: >
-    Checks that the return value of Intl.Locale.prototype.collations is an Array
-    that does not contain invalid values.
+description: The return value does not contain invalid values
 info: |
-  CollationsOfLocale ( loc )
-  ...
-  4. Let list be a List of 1 or more unique collation identifiers, which must
-  be lower case String values conforming to the type sequence from UTS 35
-  Unicode Locale Identifier, section 3.2, sorted in descending preference of
-  those in common use for string comparison in locale. The values "standard"
-  and "search" must be excluded from list.
+  10.2.3 Internal Slots
+  - The values *"standard"* and *"search"* must not be used as elements in any
+    [[SortLocaleData]].[[<locale>]].[[co]] and
+    [[SearchLocaleData]].[[<locale>]].[[co]] List.
 features: [Intl.Locale, Intl.Locale-info, Array.prototype.includes]
+locale: [ar, de, en, ja, ko, sv, tr, zh]
 ---*/
 
-const output = new Intl.Locale('en').getCollations();
-assert(output.length > 0, 'array has at least one element');
-output.forEach(c => {
-  if(['standard', 'search'].includes(c))
-    throw new Test262Error();
-});
+var tags = ["ar", "de", "en", "ja", "ko", "sv", "tr", "zh"];
+
+for (var i = 0; i < tags.length; i++) {
+  var tag = tags[i];
+  var collations = new Intl.Locale(tag).getCollations();
+  assert.notSameValue(collations.length, 0,
+    "getCollations() for " + tag + " has at least one element");
+  for (var j = 0; j < collations.length; j++) {
+    assert.notSameValue(collations[j], "standard",
+      "getCollations() for " + tag + " must not contain 'standard'");
+    assert.notSameValue(collations[j], "search",
+      "getCollations() for " + tag + " must not contain 'search'");
+  }
+}

test/intl402/Locale/prototype/getCollations/output-array.js

@@ -3,13 +3,21 @@
 
 /*---
 esid: sec-intl.locale.prototype.getCollations
-description: >
-    Checks that the return value of Intl.Locale.prototype.getCollations is an Array.
+description: The return value is an Array
 info: |
   CollationsOfLocale ( loc )
   ...
-  5. Return ! CreateArrayFromListAndPreferred( list, preferred ).
+  6. Return CreateArrayFromList(_sorted_).
 features: [Intl.Locale,Intl.Locale-info]
+locale: [ar, de, en, ja, ko, sv, tr, zh]
 ---*/
 
-assert(Array.isArray(new Intl.Locale('en').getCollations()));
+var tags = ["ar", "de", "en", "ja", "ko", "sv", "tr", "zh"];
+
+for (var i = 0; i < tags.length; i++) {
+  var tag = tags[i];
+  assert(
+    Array.isArray(new Intl.Locale(tag).getCollations()),
+    "getCollations() for " + tag + " must return an array"
+  );
+}

test/intl402/Locale/prototype/getCollations/und-language.js

@@ -0,0 +1,65 @@
+// Copyright 2026 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-Intl.Locale.prototype.getCollations
+description: >
+  Return value for tags not matching any available locale is hardcoded in spec
+info: |
+  CollationsOfLocale ( loc )
+
+  2. Let _match_ be LookupMatchingLocaleByPrefix(
+     %Intl.Collator%.[[AvailableLocales]], « _loc_.[[Locale]] »).
+  3. If _match_ is not *undefined*, then
+    ...
+  4. Else,
+    a. Let _list_ be « *"emoji"*, *"eor"* ».
+features: [Intl.Locale,Intl.Locale-info]
+---*/
+
+var undLocales = [
+  "und",
+  "und-US",
+  "und-Latn",
+  "und-Latn-US",
+  "und-u-ca-gregory",
+  "und-US-u-nu-latn",
+];
+
+for (var i = 0; i < undLocales.length; i++) {
+  var tag = undLocales[i];
+  var locale = new Intl.Locale(tag);
+  assert.sameValue(
+    locale.language,
+    "und",
+    tag + " must have language subtag 'und'"
+  );
+  assert.compareArray(
+    locale.getCollations(),
+    ["emoji", "eor"],
+    "getCollations() for " + tag + " must return the root collations"
+  );
+}
+
+// Unreserved private-use language subtags (qfz..qtz) are guaranteed to have no
+// semantics in any CLDR release, so we assume they will fall back to the
+// hardcoded root collations.
+// https://www.unicode.org/reports/tr35/tr35.html#Private_Use_Codes
+//
+// Note regarding normative change https://github.com/tc39/ecma402/pull/1072:
+// this test might pass or fail if the normative change is not implemented,
+// depending on what the environment's default locale is. It should always pass
+// regardless of the environment's default locale if the normative change is
+// implemented correctly. Try running it with LC_ALL=de in the environment, for
+// example.
+
+var privateUseTags = ["qfz", "qga-DE", "qgb-ES", "qgc-KR", "qtz-CN"];
+
+for (var i = 0; i < privateUseTags.length; i++) {
+  var tag = privateUseTags[i];
+  assert.compareArray(
+    new Intl.Locale(tag).getCollations(),
+    ["emoji", "eor"],
+    "getCollations() for unavailable locale " + tag + " must return the root collations"
+  );
+}