diff --git a/test/intl402/DateTimeFormat/prototype/format/temporal-plainyearmonth-formatting-datetime-style.js b/test/intl402/DateTimeFormat/prototype/format/temporal-plainyearmonth-formatting-datetime-style.js
index faae831916..0d4b6970ea 100644
--- a/test/intl402/DateTimeFormat/prototype/format/temporal-plainyearmonth-formatting-datetime-style.js
+++ b/test/intl402/DateTimeFormat/prototype/format/temporal-plainyearmonth-formatting-datetime-style.js
@@ -8,70 +8,78 @@ locale: [en-US]
 features: [Temporal]
 ---*/
 
-const dateFormatterShort = new Intl.DateTimeFormat("en-US", { dateStyle: "short", timeZone: "Pacific/Apia" });
-const dateFormatterMedium = new Intl.DateTimeFormat("en-US", { dateStyle: "medium", timeZone: "Pacific/Apia" });
-const dateFormatterLong = new Intl.DateTimeFormat("en-US", { dateStyle: "long", timeZone: "Pacific/Apia" });
-const dateFormatterFull = new Intl.DateTimeFormat("en-US", { dateStyle: "full", timeZone: "Pacific/Apia" });
-const timeFormatterShort = new Intl.DateTimeFormat("en-US", { timeStyle: "short", timeZone: "Pacific/Apia" });
-const timeFormatterMedium = new Intl.DateTimeFormat("en-US", { timeStyle: "medium", timeZone: "Pacific/Apia" });
-const timeFormatterLong = new Intl.DateTimeFormat("en-US", { timeStyle: "long", timeZone: "Pacific/Apia" });
-const timeFormatterFull = new Intl.DateTimeFormat("en-US", { timeStyle: "full", timeZone: "Pacific/Apia" });
-const dateTimeFormatterShort = new Intl.DateTimeFormat("en-US", { dateStyle: "short", timeStyle: "short", timeZone: "Pacific/Apia" });
-const dateTimeFormatterMedium = new Intl.DateTimeFormat("en-US", { dateStyle: "medium", timeStyle: "medium", timeZone: "Pacific/Apia" });
-const dateTimeFormatterLong = new Intl.DateTimeFormat("en-US", { dateStyle: "long", timeStyle: "long", timeZone: "Pacific/Apia" });
-const dateTimeFormatterFull = new Intl.DateTimeFormat("en-US", { dateStyle: "full", timeStyle: "full", timeZone: "Pacific/Apia" });
-const dateTimeFormatterShortLong = new Intl.DateTimeFormat("en-US", { dateStyle: "short", timeStyle: "long", timeZone: "Pacific/Apia" });
-const dateTimeFormatterShortMedium = new Intl.DateTimeFormat("en-US", { dateStyle: "short", timeStyle: "medium", timeZone: "Pacific/Apia" });
-const dateTimeFormatterShortFull = new Intl.DateTimeFormat("en-US", { dateStyle: "short", timeStyle: "full", timeZone: "Pacific/Apia" });
-const dateTimeFormatterMediumLong = new Intl.DateTimeFormat("en-US", { dateStyle: "medium", timeStyle: "long", timeZone: "Pacific/Apia" });
-const dateTimeFormatterMediumShort = new Intl.DateTimeFormat("en-US", { dateStyle: "medium", timeStyle: "short", timeZone: "Pacific/Apia" });
-const dateTimeFormatterMediumFull = new Intl.DateTimeFormat("en-US", { dateStyle: "medium", timeStyle: "full", timeZone: "Pacific/Apia" });
-const dateTimeFormatterLongMedium = new Intl.DateTimeFormat("en-US", { dateStyle: "long", timeStyle: "medium", timeZone: "Pacific/Apia" });
-const dateTimeFormatterLongShort = new Intl.DateTimeFormat("en-US", { dateStyle: "long", timeStyle: "short", timeZone: "Pacific/Apia" });
-const dateTimeFormatterLongFull = new Intl.DateTimeFormat("en-US", { dateStyle: "long", timeStyle: "full", timeZone: "Pacific/Apia" });
-const dateTimeFormatterFullMedium = new Intl.DateTimeFormat("en-US", { dateStyle: "full", timeStyle: "medium", timeZone: "Pacific/Apia" });
-const dateTimeFormatterFullShort = new Intl.DateTimeFormat("en-US", { dateStyle: "full", timeStyle: "short", timeZone: "Pacific/Apia" });
-const dateTimeFormatterFullLong = new Intl.DateTimeFormat("en-US", { dateStyle: "full", timeStyle: "long", timeZone: "Pacific/Apia" });
+const locale = "en-US";
+const timeZone = "Pacific/Apia";
+
+const dateStyles = [
+  "full", "long", "medium", "short",
+];
+
+const timeStyles = [
+  "full", "long", "medium", "short",
+];
 
 // Use a reference day so we can check that it doesn't occur in any string output
 const yearmonth = new Temporal.PlainYearMonth(2222, 1, "gregory", 30);
 
-const yearmonthResultShort = dateFormatterShort.format(yearmonth);
-// assert.sameValue(yearmonthResultShort, "1/22", "plain yearmonth, dateStyle=short");
-assert.sameValue(yearmonthResultShort.search("30"), -1, "plain yearmonth, dateStyle=short: day should not appear");
-assert.notSameValue(yearmonthResultShort.search("1"), -1, "plain yearmonth, dateStyle=short: numeric month should appear");
-assert.notSameValue(yearmonthResultShort.search("22"), -1, "plain yearmonth, dateStyle=short: 2-digit year should appear");
+const expected = {
+  // "January 2222"
+  full: {
+    year: ["2222", true],
+    month: ["1", false],
+    day: ["30", false],
+  },
 
-const yearmonthResultMedium = dateFormatterMedium.format(yearmonth);
-// assert.sameValue(yearmonthResultMedium, "Jan 2222", "plain yearmonth, dateStyle=medium");
-assert.sameValue(yearmonthResultMedium.search("30"), -1, "plain yearmonth, dateStyle=medium: day should not appear");
-assert.sameValue(yearmonthResultMedium.search("1"), -1, "plain yearmonth, dateStyle=medium: numeric month should not appear");
-assert.notSameValue(yearmonthResultMedium.search("2222"), -1, "plain yearmonth, dateStyle=medium: 4-digit year should appear");
+  // "January 2222"
+  long: {
+    year: ["2222", true],
+    month: ["1", false],
+    day: ["30", false],
+  },
 
-const yearmonthResultLong = dateFormatterLong.format(yearmonth);
-// assert.sameValue(yearmonthResultLong, "January 2222", "plain yearmonth, dateStyle=long");
-assert.sameValue(yearmonthResultLong.search("30"), -1, "plain yearmonth, dateStyle=long: day should not appear");
-assert.sameValue(yearmonthResultLong.search("1"), -1, "plain yearmonth, dateStyle=long: numeric month should not appear");
-assert.notSameValue(yearmonthResultLong.search("2222"), -1, "plain yearmonth, dateStyle=long: 4-digit year should appear");
+  // "Jan 2222"
+  medium: {
+    year: ["2222", true],
+    month: ["1", false],
+    day: ["30", false],
+  },
 
-const yearmonthResultFull = dateFormatterFull.format(yearmonth);
-// assert.sameValue(yearmonthResultFull, "January 2222", "plain yearmonth, dateStyle=full");
-assert.sameValue(yearmonthResultFull.search("30"), -1, "plain yearmonth, dateStyle=full: day should not appear");
-assert.sameValue(yearmonthResultFull.search("1"), -1, "plain yearmonth, dateStyle=full: numeric month should not appear");
-assert.notSameValue(yearmonthResultFull.search("2222"), -1, "plain yearmonth, dateStyle=full: 4-digit year should appear");
+  // "1/22"
+  short: {
+    year: ["22", true],
+    month: ["1", true],
+    day: ["30", false],
+  },
+};
 
-assert.throws(TypeError, () => timeFormatterShort.format(yearmonth), "plain yearmonth, timeStyle=short");
-assert.throws(TypeError, () => timeFormatterMedium.format(yearmonth), "plain yearmonth, timeStyle=medium");
-assert.throws(TypeError, () => timeFormatterLong.format(yearmonth), "plain yearmonth, timeStyle=long");
-assert.throws(TypeError, () => timeFormatterFull.format(yearmonth), "plain yearmonth, timeStyle=full");
+function ensureDateField(result, field, dateStyle) {
+  let [searchValue, present] = expected[dateStyle][field];
+  let verb = present ? "should" : "should not";
 
-var yearmonthResult = dateTimeFormatterShort.format(yearmonth);
-assert.sameValue(yearmonthResult, yearmonthResultShort, "plain yearmonth, dateStyle = timeStyle = short");
-yearmonthResult = dateTimeFormatterMedium.format(yearmonth);
-assert.sameValue(yearmonthResult, yearmonthResultMedium, "plain yearmonth, dateStyle = timeStyle = medium");
-yearmonthResult = dateTimeFormatterLong.format(yearmonth);
-assert.sameValue(yearmonthResult, yearmonthResultLong, "plain yearmonth, dateStyle = timeStyle = long");
-yearmonthResult = dateTimeFormatterFull.format(yearmonth);
-assert.sameValue(yearmonthResult, yearmonthResultFull, "plain yearmonth, dateStyle = timeStyle = full");
-yearmonthResult = dateTimeFormatterShortLong.format(yearmonth);
-assert.sameValue(yearmonthResult, yearmonthResultShort, "plain yearmonth, dateStyle = short, timeStyle = long");
+  assert.sameValue(
+    result.includes(searchValue),
+    present,
+    `dateStyle=${dateStyle}: ${field} ${verb} appear`
+  );
+}
+
+// timeStyle throws when no dateStyle is present.
+for (let timeStyle of timeStyles) {
+  let dtf = new Intl.DateTimeFormat(locale, {timeStyle, timeZone});
+  assert.throws(TypeError, () => dtf.format(yearmonth), `timeStyle=${timeStyle}`);
+}
+
+for (let dateStyle of dateStyles) {
+  let dtf = new Intl.DateTimeFormat(locale, {dateStyle, timeZone});
+  let result = dtf.format(yearmonth);
+
+  ensureDateField(result, "year", dateStyle);
+  ensureDateField(result, "month", dateStyle);
+  ensureDateField(result, "day", dateStyle);
+
+  // timeStyle is ignored when dateStyle is present.
+  for (let timeStyle of timeStyles) {
+    let dtf = new Intl.DateTimeFormat(locale, {dateStyle, timeStyle, timeZone});
+    assert.sameValue(dtf.format(yearmonth), result, `dateStyle = ${dateStyle}, timeStyle = ${timeStyle}`);
+  }
+}