diff --git a/tests/phpunit/tests/http/base.php b/tests/phpunit/tests/http/base.php
index 14a58c4a0c..c95fac303e 100644
--- a/tests/phpunit/tests/http/base.php
+++ b/tests/phpunit/tests/http/base.php
@@ -52,14 +52,14 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 	function test_redirect_on_301() {
 		// 5 : 5 & 301
 		$res = wp_remote_request($this->redirection_script . '?code=301&rt=' . 5, array('redirection' => 5) );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals(200, (int)$res['response']['code'] );
 	}
 
 	function test_redirect_on_302() {
 		// 5 : 5 & 302
 		$res = wp_remote_request($this->redirection_script . '?code=302&rt=' . 5, array('redirection' => 5) );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals(200, (int)$res['response']['code'] );
 	}
 
@@ -69,7 +69,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 	function test_redirect_on_301_no_redirect() {
 		// 5 > 0 & 301
 		$res = wp_remote_request($this->redirection_script . '?code=301&rt=' . 5, array('redirection' => 0) );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals(301, (int)$res['response']['code'] );
 	}
 
@@ -79,21 +79,21 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 	function test_redirect_on_302_no_redirect() {
 		// 5 > 0 & 302
 		$res = wp_remote_request($this->redirection_script . '?code=302&rt=' . 5, array('redirection' => 0) );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals(302, (int)$res['response']['code'] );
 	}
 
 	function test_redirections_equal() {
 		// 5 - 5
 		$res = wp_remote_request($this->redirection_script . '?rt=' . 5, array('redirection' => 5) );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals(200, (int)$res['response']['code'] );
 	}
 
 	function test_no_head_redirections() {
 		// No redirections on HEAD request:
 		$res = wp_remote_request($this->redirection_script . '?code=302&rt=' . 1, array('method' => 'HEAD') );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals( 302, (int)$res['response']['code'] );
 	}
 
@@ -103,7 +103,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 	function test_redirect_on_head() {
 		// Redirections on HEAD request when Requested
 		$res = wp_remote_request($this->redirection_script . '?rt=' . 5, array('redirection' => 5, 'method' => 'HEAD') );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals( 200, (int)$res['response']['code'] );
 	}
 
@@ -122,7 +122,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 	function test_redirections_less_edgecase() {
 		// 4 < 5 (close edgecase)
 		$res = wp_remote_request($this->redirection_script . '?rt=' . 4, array('redirection' => 5) );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 	}
 
 	/**
@@ -131,7 +131,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 	function test_redirections_zero_redirections_specified() {
 		// 0 redirections asked for, Should return the document?
 		$res = wp_remote_request($this->redirection_script . '?code=302&rt=' . 5, array('redirection' => 0) );
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals( 302, (int)$res['response']['code'] );
 	}
 
@@ -143,7 +143,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 	function test_location_header_on_201() {
 		// Prints PASS on initial load, FAIL if the client follows the specified redirection
 		$res = wp_remote_request( $this->redirection_script . '?201-location=true' );
-		$this->assertFalse( is_wp_error( $res ) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals( 'PASS', $res['body']);
 	}
 
@@ -169,7 +169,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 		$headers = array('test1' => 'test', 'test2' => 0, 'test3' => '');
 		$res = wp_remote_request( $this->redirection_script . '?header-check', array('headers' => $headers) );
 
-		$this->assertFalse( is_wp_error($res) );
+		$this->assertNotWPError( $res );
 
 		$headers = array();
 		foreach ( explode("\n", $res['body']) as $key => $value ) {
@@ -198,7 +198,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 			unlink( $res['filename'] );
 		}
 
-		$this->assertFalse( is_wp_error( $res ) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals( '', $res['body'] ); // The body should be empty.
 		$this->assertEquals( $size, $res['headers']['content-length'] ); // Check the headers are returned (and the size is the same..)
 		$this->assertEquals( $size, $filesize ); // Check that the file is written to disk correctly without any extra characters
@@ -219,7 +219,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 			unlink( $res['filename'] );
 		}
 
-		$this->assertFalse( is_wp_error( $res ) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals( $size, $filesize ); // Check that the file is written to disk correctly without any extra characters
 
 	}
@@ -235,7 +235,7 @@ abstract class WP_HTTP_UnitTestCase extends WP_UnitTestCase {
 
 		$res = wp_remote_request( $url, array( 'timeout' => 30, 'limit_response_size' => $size ) );
 
-		$this->assertFalse( is_wp_error( $res ) );
+		$this->assertNotWPError( $res );
 		$this->assertEquals( $size, strlen( $res['body'] ) );
 	}
 
diff --git a/tests/phpunit/tests/term.php b/tests/phpunit/tests/term.php
index 024179b73d..0713e29219 100644
--- a/tests/phpunit/tests/term.php
+++ b/tests/phpunit/tests/term.php
@@ -411,7 +411,7 @@ class Tests_Term extends WP_UnitTestCase {
 
 		$t = wp_insert_category( array( 'cat_name' => $term ) );
 		$this->assertTrue( is_numeric($t) );
-		$this->assertFalse( is_wp_error($t) );
+		$this->assertNotWPError( $t );
 		$this->assertTrue( $t > 0 );
 		$this->assertEquals( $initial_count + 1, wp_count_terms( 'category' ) );
 
diff --git a/tests/phpunit/tests/term/wpInsertTerm.php b/tests/phpunit/tests/term/wpInsertTerm.php
index 3cac325d0e..0a63d26976 100644
--- a/tests/phpunit/tests/term/wpInsertTerm.php
+++ b/tests/phpunit/tests/term/wpInsertTerm.php
@@ -27,7 +27,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 
 		$t = wp_insert_term( $term, $taxonomy );
 		$this->assertInternalType( 'array', $t );
-		$this->assertFalse( is_wp_error($t) );
+		$this->assertNotWPError( $t );
 		$this->assertTrue( $t['term_id'] > 0 );
 		$this->assertTrue( $t['term_taxonomy_id'] > 0 );
 		$this->assertEquals( $initial_count + 1, wp_count_terms( $taxonomy ) );
@@ -161,12 +161,12 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 	 */
 	public function test_wp_insert_term_duplicate_name() {
 		$term = $this->factory->tag->create_and_get( array( 'name' => 'Bozo' ) );
-		$this->assertFalse( is_wp_error( $term ) );
+		$this->assertNotWPError( $term );
 		$this->assertTrue( empty( $term->errors ) );
 
 		// Test existing term name with unique slug
 		$term1 = $this->factory->tag->create( array( 'name' => 'Bozo', 'slug' => 'bozo1' ) );
-		$this->assertFalse( is_wp_error( $term1 ) );
+		$this->assertNotWPError( $term1 );
 
 		// Test an existing term name
 		$term2 = $this->factory->tag->create( array( 'name' => 'Bozo' ) );
@@ -200,21 +200,21 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 		$this->assertCount( 4, array_unique( wp_list_pluck( $terms, 'slug' ) ) );
 
 		$term13 = $this->factory->tag->create( array( 'name' => 'A' ) );
-		$this->assertFalse( is_wp_error( $term13 ) );
+		$this->assertNotWPError( $term13 );
 		$term14 = $this->factory->tag->create( array( 'name' => 'A' ) );
 		$this->assertTrue( is_wp_error( $term14 ) );
 		$term15 = $this->factory->tag->create( array( 'name' => 'A+', 'slug' => 'a' ) );
-		$this->assertFalse( is_wp_error( $term15 ) );
+		$this->assertNotWPError( $term15 );
 		$term16 = $this->factory->tag->create( array( 'name' => 'A+' ) );
 		$this->assertTrue( is_wp_error( $term16 ) );
 		$term17 = $this->factory->tag->create( array( 'name' => 'A++' ) );
-		$this->assertFalse( is_wp_error( $term17 ) );
+		$this->assertNotWPError( $term17 );
 		$term18 = $this->factory->tag->create( array( 'name' => 'A-', 'slug' => 'a' ) );
-		$this->assertFalse( is_wp_error( $term18 ) );
+		$this->assertNotWPError( $term18 );
 		$term19 = $this->factory->tag->create( array( 'name' => 'A-' ) );
 		$this->assertTrue( is_wp_error( $term19 ) );
 		$term20 = $this->factory->tag->create( array( 'name' => 'A--' ) );
-		$this->assertFalse( is_wp_error( $term20 ) );
+		$this->assertNotWPError( $term20 );
 	}
 
 	/**
@@ -276,7 +276,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 			'slug' => 'foo-unique',
 		) );
 
-		$this->assertFalse( is_wp_error( $t2 ) );
+		$this->assertNotWPError( $t2 );
 
 		$t2_term = get_term( $t2['term_id'], 'wptests_tax' );
 		$this->assertSame( 'foo-unique', $t2_term->slug );
@@ -368,7 +368,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 			'slug' => 'bar',
 		) );
 
-		$this->assertFalse( is_wp_error( $t4 ) );
+		$this->assertNotWPError( $t4 );
 		$t4_term = get_term( $t4['term_id'], 'wptests_tax' );
 
 		// `wp_unique_term_slug()` allows term creation but iterates the slug.
@@ -391,7 +391,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 			'slug' => 'foo-unique',
 		) );
 
-		$this->assertFalse( is_wp_error( $t2 ) );
+		$this->assertNotWPError( $t2 );
 
 		$t2_term = get_term( $t2['term_id'], 'wptests_tax' );
 		$this->assertSame( 'foo-unique', $t2_term->slug );
@@ -455,7 +455,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 			'slug' => 'foo',
 		) );
 
-		$this->assertFalse( is_wp_error( $created ) );
+		$this->assertNotWPError( $created );
 
 		$new_term = get_term( $created['term_id'], 'wptests_tax_2' );
 
@@ -486,7 +486,7 @@ class Tests_Term_WpInsertTerm extends WP_UnitTestCase {
 			'slug' => 'foo',
 		) );
 
-		$this->assertFalse( is_wp_error( $created ) );
+		$this->assertNotWPError( $created );
 
 		$new_term = get_term( $created['term_id'], 'wptests_tax_2' );
 
diff --git a/tests/phpunit/tests/term/wpUpdateTerm.php b/tests/phpunit/tests/term/wpUpdateTerm.php
index 47ec5692c4..71495d7175 100644
--- a/tests/phpunit/tests/term/wpUpdateTerm.php
+++ b/tests/phpunit/tests/term/wpUpdateTerm.php
@@ -188,7 +188,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 			'slug' => 'foo',
 		) );
 
-		$this->assertFalse( is_wp_error( $updated ) );
+		$this->assertNotWPError( $updated );
 
 		$t1_term = get_term( $t1, 'wptests_tax' );
 		$t2_term = get_term( $t2, 'wptests_tax_2' );
@@ -218,7 +218,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 			'name' => 'Foo',
 		) );
 
-		$this->assertFalse( is_wp_error( $updated ) );
+		$this->assertNotWPError( $updated );
 
 		$t2_term = get_term( $t2, 'wptests_tax_2' );
 		$this->assertSame( 'Foo', $t2_term->name );
@@ -256,7 +256,7 @@ class Tests_Term_WpUpdateTerm extends WP_UnitTestCase {
 			'name' => 'Bar',
 		) );
 
-		$this->assertFalse( is_wp_error( $updated ) );
+		$this->assertNotWPError( $updated );
 
 		$t3_term = get_term( $t3, 'wptests_tax' );
 		$this->assertSame( 'Bar', $t3_term->name );