diff --git a/test/intl402/DurationFormat/prototype/format/length.js b/test/intl402/DurationFormat/prototype/format/length.js
new file mode 100644
index 0000000000..94bfeb3499
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/format/length.js
@@ -0,0 +1,35 @@
+// Copyright 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.datetimeformat.prototype.format
+description: >
+  Intl.DateTimeFormat.prototype.format.length is 1.
+info: |
+  Intl.DurationFormat.prototype.format ( duration )
+
+  17 ECMAScript Standard Built-in Objects:
+
+    Every built-in function object, including constructors, has a length
+    property whose value is an integer. Unless otherwise specified, this
+    value is equal to the largest number of named arguments shown in the
+    subclause headings for the function description. Optional parameters
+    (which are indicated with brackets: [ ]) or rest parameters (which
+    are shown using the form «...name») are not included in the default
+    argument count.
+    Unless otherwise specified, the length property of a built-in function
+    object has the attributes { [[Writable]]: false, [[Enumerable]]: false,
+    [[Configurable]]: true }.
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(Intl.DateTimeFormat.prototype.format.length, 1);
+
+verifyProperty(Intl.DurationFormat.prototype.format, "length", {
+  value: 1,
+  writable: false,
+  enumerable: false,
+  configurable: true
+});
+
diff --git a/test/intl402/DurationFormat/prototype/formatToParts/length.js b/test/intl402/DurationFormat/prototype/formatToParts/length.js
new file mode 100644
index 0000000000..edc21dab52
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/formatToParts/length.js
@@ -0,0 +1,35 @@
+// Copyright 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.datetimeformat.prototype.formatToParts
+description: >
+  Intl.DateTimeFormat.prototype.formatToParts.length is 1.
+info: |
+  Intl.DateTimeFormat.prototype.formatToParts ( date )
+
+  17 ECMAScript Standard Built-in Objects:
+
+    Every built-in function object, including constructors, has a length
+    property whose value is an integer. Unless otherwise specified, this
+    value is equal to the largest number of named arguments shown in the
+    subclause headings for the function description. Optional parameters
+    (which are indicated with brackets: [ ]) or rest parameters (which
+    are shown using the form «...name») are not included in the default
+    argument count.
+    Unless otherwise specified, the length property of a built-in function
+    object has the attributes { [[Writable]]: false, [[Enumerable]]: false,
+    [[Configurable]]: true }.
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(Intl.DateTimeFormat.prototype.formatToParts.length, 1);
+
+verifyProperty(Intl.DurationFormat.prototype.formatToParts, "length", {
+  value: 1,
+  writable: false,
+  enumerable: false,
+  configurable: true
+});
+
diff --git a/test/intl402/DurationFormat/prototype/formatToParts/name.js b/test/intl402/DurationFormat/prototype/formatToParts/name.js
new file mode 100644
index 0000000000..934d9cbe97
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/formatToParts/name.js
@@ -0,0 +1,26 @@
+// Copyright 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-Intl.DurationFormat.prototype.formatToParts
+description: Checks the "name" property of Intl.DurationFormat.prototype.formatToParts().
+info: |
+  17 ECMAScript Standard Built-in Objects:
+    Every built-in Function object, including constructors, that is not
+    identified as an anonymous function has a name property whose value
+    is a String.
+
+    Unless otherwise specified, the name property of a built-in Function
+    object, if it exists, has the attributes { [[Writable]]: false,
+    [[Enumerable]]: false, [[Configurable]]: true }.
+
+includes: [propertyHelper.js]
+features: [Intl.DurationFormat]
+---*/
+
+verifyProperty(Intl.DurationFormat.prototype.formatToParts, "name", {
+  value: "formatToParts",
+  writable: false,
+  enumerable: false,
+  configurable: true
+});
diff --git a/test/intl402/DurationFormat/prototype/formatToParts/prop-desc.js b/test/intl402/DurationFormat/prototype/formatToParts/prop-desc.js
new file mode 100644
index 0000000000..b00ca30f86
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/formatToParts/prop-desc.js
@@ -0,0 +1,21 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-Intl.DurationFormat.prototype.formatToParts
+description: Property descriptor of Intl.DurationFormat.prototype.formatToParts
+includes: [propertyHelper.js]
+features: [Intl.DurationFormat]
+---*/
+
+assert.sameValue(
+  typeof Intl.DurationFormat.prototype.formatToParts,
+  'function',
+  '`typeof Intl.DurationFormat.prototype.formatToParts` is `function`'
+);
+
+verifyProperty(Intl.DurationFormat.prototype, 'formatToParts', {
+  enumerable: false,
+  writable: true,
+  configurable: true,
+});
diff --git a/test/intl402/DurationFormat/prototype/formatToParts/throw-invoked-as-func.js b/test/intl402/DurationFormat/prototype/formatToParts/throw-invoked-as-func.js
new file mode 100644
index 0000000000..66af26956c
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/formatToParts/throw-invoked-as-func.js
@@ -0,0 +1,21 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.DurationFormat.prototype.format
+description: basic tests internal slot initialization and call receiver errors
+info: |
+  Intl.DurationFormat.prototype.formatToParts ( duration )
+  (...)
+    2. Perform ? RequireInternalSlot(df, [[InitializedDurationFormat]]).
+features: [Intl.DurationFormat]
+---*/
+
+const df = new Intl.DurationFormat();
+
+// Perform ? RequireInternalSlot(df, [[InitializedDurationFormat]]).
+let f = df['formatToParts'];
+
+assert.sameValue(typeof f, 'function');
+assert.throws(TypeError, () => { f('PT12.3456S') });
+
diff --git a/test/intl402/DurationFormat/prototype/resolvedOptions/length.js b/test/intl402/DurationFormat/prototype/resolvedOptions/length.js
new file mode 100644
index 0000000000..dfae25b004
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/resolvedOptions/length.js
@@ -0,0 +1,35 @@
+// Copyright 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.DurationFormat.prototype.resolvedoptions
+description: >
+  Intl.DurationFormat.prototype.resolvedOptions.length is 0.
+info: |
+  Intl.DurationFormat.prototype.resolvedOptions ()
+
+  17 ECMAScript Standard Built-in Objects:
+
+    Every built-in function object, including constructors, has a length
+    property whose value is an integer. Unless otherwise specified, this
+    value is equal to the largest number of named arguments shown in the
+    subclause headings for the function description. Optional parameters
+    (which are indicated with brackets: [ ]) or rest parameters (which
+    are shown using the form «...name») are not included in the default
+    argument count.
+    Unless otherwise specified, the length property of a built-in function
+    object has the attributes { [[Writable]]: false, [[Enumerable]]: false,
+    [[Configurable]]: true }.
+
+includes: [propertyHelper.js]
+---*/
+
+assert.sameValue(Intl.DurationFormat.prototype.resolvedOptions.length, 0);
+
+verifyProperty(Intl.DurationFormat.prototype.resolvedOptions, "length", {
+  value: 0,
+  writable: false,
+  enumerable: false,
+  configurable: true
+});
+
diff --git a/test/intl402/DurationFormat/prototype/resolvedOptions/name.js b/test/intl402/DurationFormat/prototype/resolvedOptions/name.js
new file mode 100644
index 0000000000..2c486cd924
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/resolvedOptions/name.js
@@ -0,0 +1,26 @@
+// Copyright 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-Intl.DurationFormat.prototype.resolvedOptions
+description: Checks the "name" property of Intl.DurationFormat.prototype.resolvedOptions().
+info: |
+  17 ECMAScript Standard Built-in Objects:
+    Every built-in Function object, including constructors, that is not
+    identified as an anonymous function has a name property whose value
+    is a String.
+
+    Unless otherwise specified, the name property of a built-in Function
+    object, if it exists, has the attributes { [[Writable]]: false,
+    [[Enumerable]]: false, [[Configurable]]: true }.
+
+includes: [propertyHelper.js]
+features: [Intl.DurationFormat]
+---*/
+
+verifyProperty(Intl.DurationFormat.prototype.resolvedOptions, "name", {
+  value: "resolvedOptions",
+  writable: false,
+  enumerable: false,
+  configurable: true
+});
diff --git a/test/intl402/DurationFormat/prototype/resolvedOptions/prop-desc.js b/test/intl402/DurationFormat/prototype/resolvedOptions/prop-desc.js
new file mode 100644
index 0000000000..58d1bd5529
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/resolvedOptions/prop-desc.js
@@ -0,0 +1,21 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-Intl.DurationFormat.prototype.resolvedOptions
+description: Property descriptor of Intl.DurationFormat.prototype.resolvedOptions
+includes: [propertyHelper.js]
+features: [Intl.DurationFormat]
+---*/
+
+assert.sameValue(
+  typeof Intl.DurationFormat.prototype.resolvedOptions,
+  'function',
+  '`typeof Intl.DurationFormat.prototype.resolvedOptions` is `function`'
+);
+
+verifyProperty(Intl.DurationFormat.prototype, 'resolvedOptions', {
+  enumerable: false,
+  writable: true,
+  configurable: true,
+});
diff --git a/test/intl402/DurationFormat/prototype/resolvedOptions/throw-invoked-as-func.js b/test/intl402/DurationFormat/prototype/resolvedOptions/throw-invoked-as-func.js
new file mode 100644
index 0000000000..09a1e0fe6e
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/resolvedOptions/throw-invoked-as-func.js
@@ -0,0 +1,21 @@
+// Copyright (C) 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.DurationFormat.prototype.resolvedOptions
+description: basic tests internal slot initialization and call receiver errors
+info: |
+  Intl.DurationFormat.prototype.resolvedOptions ( )
+  (...)
+    2. Perform ? RequireInternalSlot(df, [[InitializedDurationFormat]]).
+features: [Intl.DurationFormat]
+---*/
+
+const df = new Intl.DurationFormat();
+
+// Perform ? RequireInternalSlot(df, [[InitializedDurationFormat]]).
+let f = df['resolvedOptions'];
+
+assert.sameValue(typeof f, 'function');
+assert.throws(TypeError, () => { f() });
+
diff --git a/test/intl402/DurationFormat/prototype/toStringTag/toString.js b/test/intl402/DurationFormat/prototype/toStringTag/toString.js
new file mode 100644
index 0000000000..434f875935
--- /dev/null
+++ b/test/intl402/DurationFormat/prototype/toStringTag/toString.js
@@ -0,0 +1,17 @@
+// Copyright 2022 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.DurationFormat.prototype-@@tostringtag
+description: >
+  Object.prototype.toString utilizes Intl.DurationFormat.prototype[@@toStringTag].
+info: |
+  Intl.DurationFormat.prototype [ @@toStringTag ]
+
+  The initial value of the @@toStringTag property is the string value "Intl.DurationFormat".
+
+features: [Intl.DurationFormat, Symbol.toStringTag]
+---*/
+
+assert.sameValue(Object.prototype.toString.call(Intl.DurationFormat.prototype), "[object Intl.DurationFormat]");
+assert.sameValue(Object.prototype.toString.call(new Intl.DurationFormat()), "[object Intl.DurationFormat]");
diff --git a/test/intl402/DurationFormat/prototype/toStringTag.js b/test/intl402/DurationFormat/prototype/toStringTag/toStringTag.js
similarity index 70%
rename from test/intl402/DurationFormat/prototype/toStringTag.js
rename to test/intl402/DurationFormat/prototype/toStringTag/toStringTag.js
index 13544875ae..5523c92225 100644
--- a/test/intl402/DurationFormat/prototype/toStringTag.js
+++ b/test/intl402/DurationFormat/prototype/toStringTag/toStringTag.js
@@ -1,12 +1,18 @@
 // Copyright (C) 2021 Nikhil Singhal. All rights reserved.
 // This code is governed by the BSD license found in the LICENSE file.
+// Copyright 2022 Igalia, S.L. All rights reserved.
 
 /*---
-esid: sec-Intl.DurationFormat.prototype-@@tostringtag
-description: Checks prototype's toStringTag value
+esid: sec-intl.DurationFormat.prototype-@@tostringtag
+description: >
+  Property descriptor of Intl.DurationFormat.prototype[@@toStringTag].
 info: |
+  Intl.DurationFormat.prototype [ @@toStringTag ]
+
   The initial value of the @@toStringTag property is the string value "Intl.DurationFormat".
+
   This property has the attributes { [[Writable]]: false, [[Enumerable]]: false, [[Configurable]]: true }.
+
 features: [Intl.DurationFormat, Symbol.toStringTag]
 includes: [propertyHelper.js]
 ---*/