diff --git a/spring-test/src/main/java/org/springframework/test/http/HttpHeadersAssert.java b/spring-test/src/main/java/org/springframework/test/http/HttpHeadersAssert.java
index 8e6552e4d3..aa214af384 100644
--- a/spring-test/src/main/java/org/springframework/test/http/HttpHeadersAssert.java
+++ b/spring-test/src/main/java/org/springframework/test/http/HttpHeadersAssert.java
@@ -86,7 +86,7 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	 */
 	public HttpHeadersAssert containsOnlyHeaders(String... names) {
 		this.namesAssert
-				.as("check headers contains only HTTP headers '%s'", Arrays.toString(names))
+				.as("check headers contain only HTTP headers '%s'", Arrays.toString(names))
 				.containsOnly(names);
 		return this.myself;
 	}
@@ -98,7 +98,7 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	 */
 	public HttpHeadersAssert doesNotContainHeader(String name) {
 		this.namesAssert
-				.as("check headers does not contain HTTP header '%s'", name)
+				.as("check headers do not contain HTTP header '%s'", name)
 				.doesNotContain(name);
 		return this.myself;
 	}
@@ -111,7 +111,7 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	 */
 	public HttpHeadersAssert doesNotContainHeaders(String... names) {
 		this.namesAssert
-				.as("check headers does not contain HTTP headers '%s'", Arrays.toString(names))
+				.as("check headers do not contain HTTP headers '%s'", Arrays.toString(names))
 				.doesNotContain(names);
 		return this.myself;
 	}
@@ -119,15 +119,16 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	/**
 	 * Verify that the actual HTTP headers contain a header with the given
 	 * {@code name} that satisfies the given {@code valueRequirements}.
-	 * @param name the name of an HTTP header that should not be present
+	 * @param name the name of the header
 	 * @param valueRequirements the group of assertions to run against the
 	 * values of the header with the given name
+	 * @since 7.0
 	 */
 	@SuppressWarnings("unchecked")
 	public HttpHeadersAssert hasHeaderSatisfying(String name, Consumer<List<String>> valueRequirements) {
 		containsHeader(name);
 		Assertions.assertThat(this.actual.get(name))
-				.as("check primary value for HTTP header '%s'", name)
+				.as("check all values for HTTP header '%s'", name)
 				.satisfies(values -> valueRequirements.accept((List<String>) values));
 		return this.myself;
 	}
@@ -135,7 +136,7 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	/**
 	 * Verify that the actual HTTP headers contain a header with the given
 	 * {@code name} and {@link String} primary {@code value}.
-	 * @param name the name of the cookie
+	 * @param name the name of the header
 	 * @param value the expected value of the header
 	 */
 	public HttpHeadersAssert hasValue(String name, String value) {
@@ -148,8 +149,8 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 
 	/**
 	 * Verify that the actual HTTP headers contain a header with the given
-	 * {@code name} and {@link Long} primary {@code value}.
-	 * @param name the name of the cookie
+	 * {@code name} and {@code long} primary {@code value}.
+	 * @param name the name of the header
 	 * @param value the expected value of the header
 	 */
 	public HttpHeadersAssert hasValue(String name, long value) {
@@ -163,7 +164,7 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	/**
 	 * Verify that the actual HTTP headers contain a header with the given
 	 * {@code name} and {@link Instant} primary {@code value}.
-	 * @param name the name of the cookie
+	 * @param name the name of the header
 	 * @param value the expected value of the header
 	 */
 	public HttpHeadersAssert hasValue(String name, Instant value) {
@@ -178,7 +179,7 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	 * Verify that the actual HTTP headers contain a header with the given
 	 * {@code name} and {@link String} primary {@code value}.
 	 * <p>This assertion fails if the header has secondary values.
-	 * @param name the name of the cookie
+	 * @param name the name of the header
 	 * @param value the expected only value of the header
 	 * @since 7.0
 	 */
@@ -189,9 +190,9 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 
 	/**
 	 * Verify that the actual HTTP headers contain a header with the given
-	 * {@code name} and {@link Long} primary {@code value}.
+	 * {@code name} and {@code long} primary {@code value}.
 	 * <p>This assertion fails if the header has secondary values.
-	 * @param name the name of the cookie
+	 * @param name the name of the header
 	 * @param value the expected value of the header
 	 * @since 7.0
 	 */
@@ -204,7 +205,7 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	 * Verify that the actual HTTP headers contain a header with the given
 	 * {@code name} and {@link Instant} primary {@code value}.
 	 * <p>This assertion fails if the header has secondary values.
-	 * @param name the name of the cookie
+	 * @param name the name of the header
 	 * @param value the expected value of the header
 	 * @since 7.0
 	 */
@@ -265,7 +266,7 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	}
 
 	/**
-	 * Verify that there is exactly {@code expected} headers present, when
+	 * Verify that there are exactly {@code expected} headers present, when
 	 * considering header names in a case-insensitive manner.
 	 * @param expected the expected number of headers
 	 */
@@ -293,11 +294,13 @@ public class HttpHeadersAssert extends AbstractObjectAssert<HttpHeadersAssert, H
 	private HttpHeadersAssert doesNotHaveSecondaryValues(String name) {
 		containsHeader(name);
 		List<String> values = this.actual.get(name);
-		int size = (values != null) ? values.size() : 0;
-		Assertions.assertThat(size)
-				.withFailMessage("Expected HTTP header '%s' to be present " +
-						"without secondary values, but found <%s> secondary values", name, size - 1)
-				.isOne();
+		if (values != null && !values.isEmpty()) {
+			int size = values.size();
+			Assertions.assertThat(size)
+					.withFailMessage("Expected HTTP header '%s' to be present " +
+							"without secondary values, but found <%s> secondary value(s)", name, size - 1)
+					.isOne();
+		}
 		return this.myself;
 	}
 
diff --git a/spring-test/src/test/java/org/springframework/test/http/HttpHeadersAssertTests.java b/spring-test/src/test/java/org/springframework/test/http/HttpHeadersAssertTests.java
index 195543acac..eb8fd926d6 100644
--- a/spring-test/src/test/java/org/springframework/test/http/HttpHeadersAssertTests.java
+++ b/spring-test/src/test/java/org/springframework/test/http/HttpHeadersAssertTests.java
@@ -84,7 +84,7 @@ class HttpHeadersAssertTests {
 		headers.add("name2", "value2");
 		assertThatExceptionOfType(AssertionError.class)
 				.isThrownBy(() -> assertThat(headers).containsOnlyHeaders("name1", "name2", "name3"))
-				.withMessageContainingAll("check headers contains only HTTP headers",
+				.withMessageContainingAll("check headers contain only HTTP headers",
 						"could not find the following element(s)", "[\"name3\"]");
 	}
 
@@ -96,7 +96,7 @@ class HttpHeadersAssertTests {
 		headers.add("name3", "value3");
 		assertThatExceptionOfType(AssertionError.class)
 				.isThrownBy(() -> assertThat(headers).containsOnlyHeaders("name1", "name2"))
-				.withMessageContainingAll("check headers contains only HTTP headers",
+				.withMessageContainingAll("check headers contain only HTTP headers",
 						"the following element(s) were unexpected", "[\"name3\"]");
 	}
 
@@ -185,10 +185,10 @@ class HttpHeadersAssertTests {
 
 	@Test
 	void hasValueWithNonPresentHeader() {
-		HttpHeaders map = new HttpHeaders();
-		map.add("test-header", "a");
+		HttpHeaders headers = new HttpHeaders();
+		headers.add("test-header", "a");
 		assertThatExceptionOfType(AssertionError.class)
-				.isThrownBy(() -> assertThat(map).hasValue("wrong-name", "a"))
+				.isThrownBy(() -> assertThat(headers).hasValue("wrong-name", "a"))
 				.withMessageContainingAll("HTTP header", "test-header", "wrong-name");
 	}
 
@@ -201,19 +201,19 @@ class HttpHeadersAssertTests {
 
 	@Test
 	void hasValueWithLongMatchOnSecondaryValue() {
-		HttpHeaders map = new HttpHeaders();
-		map.addAll("header", List.of("123", "456", "789"));
+		HttpHeaders headers = new HttpHeaders();
+		headers.addAll("header", List.of("123", "456", "789"));
 		assertThatExceptionOfType(AssertionError.class)
-				.isThrownBy(() -> assertThat(map).hasValue("header", 456))
+				.isThrownBy(() -> assertThat(headers).hasValue("header", 456))
 				.withMessageContainingAll("check primary long value for HTTP header 'header'", "123", "456");
 	}
 
 	@Test
 	void hasValueWithNoLongMatch() {
-		HttpHeaders map = new HttpHeaders();
-		map.addAll("header", List.of("123", "456", "789"));
+		HttpHeaders headers = new HttpHeaders();
+		headers.addAll("header", List.of("123", "456", "789"));
 		assertThatExceptionOfType(AssertionError.class)
-				.isThrownBy(() -> assertThat(map).hasValue("wrong-name", 456))
+				.isThrownBy(() -> assertThat(headers).hasValue("wrong-name", 456))
 				.withMessageContainingAll("HTTP header", "header", "wrong-name");
 	}
 
@@ -228,20 +228,20 @@ class HttpHeadersAssertTests {
 	@Test
 	void hasValueWithNoInstantMatch() {
 		Instant instant = Instant.now();
-		HttpHeaders map = new HttpHeaders();
-		map.setInstant("header", instant);
+		HttpHeaders headers = new HttpHeaders();
+		headers.setInstant("header", instant);
 		assertThatExceptionOfType(AssertionError.class)
-				.isThrownBy(() -> assertThat(map).hasValue("wrong-name", instant.minusSeconds(30)))
+				.isThrownBy(() -> assertThat(headers).hasValue("wrong-name", instant.minusSeconds(30)))
 				.withMessageContainingAll("HTTP header", "header", "wrong-name");
 	}
 
 	@Test
 	void hasValueWithNoInstantMatchOneSecOfDifference() {
 		Instant instant = Instant.now();
-		HttpHeaders map = new HttpHeaders();
-		map.setInstant("header", instant);
+		HttpHeaders headers = new HttpHeaders();
+		headers.setInstant("header", instant);
 		assertThatExceptionOfType(AssertionError.class)
-				.isThrownBy(() -> assertThat(map).hasValue("wrong-name", instant.minusSeconds(1)))
+				.isThrownBy(() -> assertThat(headers).hasValue("wrong-name", instant.minusSeconds(1)))
 				.withMessageContainingAll("HTTP header", "header", "wrong-name");
 	}
 
@@ -259,7 +259,7 @@ class HttpHeadersAssertTests {
 		assertThatExceptionOfType(AssertionError.class)
 				.isThrownBy(() -> assertThat(headers).hasSingleValue("header", "first"))
 				.withMessage("Expected HTTP header 'header' to be present without secondary values, " +
-						"but found <2> secondary values");
+						"but found <2> secondary value(s)");
 	}
 
 	@Test
@@ -276,7 +276,7 @@ class HttpHeadersAssertTests {
 		assertThatExceptionOfType(AssertionError.class)
 				.isThrownBy(() -> assertThat(headers).hasSingleValue("header", 123))
 				.withMessage("Expected HTTP header 'header' to be present without secondary values, " +
-						"but found <2> secondary values");
+						"but found <2> secondary value(s)");
 	}
 
 	@Test
@@ -296,7 +296,7 @@ class HttpHeadersAssertTests {
 		assertThatExceptionOfType(AssertionError.class)
 				.isThrownBy(() -> assertThat(headers).hasSingleValue("header", instant.minusSeconds(30)))
 				.withMessage("Expected HTTP header 'header' to be present without secondary values, " +
-						"but found <1> secondary values");
+						"but found <1> secondary value(s)");
 	}
 
 	@Test