diff --git a/tests/phpunit/tests/admin/includesUpdateCore.php b/tests/phpunit/tests/admin/includesUpdateCore.php
index 82ecfa62fa..2eda876c39 100644
--- a/tests/phpunit/tests/admin/includesUpdateCore.php
+++ b/tests/phpunit/tests/admin/includesUpdateCore.php
@@ -29,6 +29,6 @@ class Tests_Admin_IncludesUpdateCore extends WP_UnitTestCase {
 	 * @param string $file File name.
 	 */
 	public function test_new_files_are_not_in_old_files_array_compiled( $file ) {
-		$this->assertFalse( file_exists( dirname( ABSPATH ) . '/build/' . $file ) );
+		$this->assertFileNotExists( dirname( ABSPATH ) . '/build/' . $file );
 	}
 }
diff --git a/tests/phpunit/tests/ajax/MediaEdit.php b/tests/phpunit/tests/ajax/MediaEdit.php
index 2ec07562cc..0528299e80 100644
--- a/tests/phpunit/tests/ajax/MediaEdit.php
+++ b/tests/phpunit/tests/ajax/MediaEdit.php
@@ -94,7 +94,7 @@ class Tests_Ajax_MediaEdit extends WP_Ajax_UnitTestCase {
 		}
 
 		foreach ( $files_that_shouldnt_exist as $file ) {
-			$this->assertFalse( file_exists( $file ), 'IMAGE_EDIT_OVERWRITE is leaving garbage image files behind.' );
+			$this->assertFileNotExists( $file, 'IMAGE_EDIT_OVERWRITE is leaving garbage image files behind.' );
 		}
 	}
 }
diff --git a/tests/phpunit/tests/dependencies/backbonejs.php b/tests/phpunit/tests/dependencies/backbonejs.php
index e55431eaeb..4c276ad898 100644
--- a/tests/phpunit/tests/dependencies/backbonejs.php
+++ b/tests/phpunit/tests/dependencies/backbonejs.php
@@ -8,7 +8,7 @@ class Tests_Dependencies_Backbonejs extends WP_UnitTestCase {
 
 	function test_exclusion_of_sourcemaps() {
 		$file = ABSPATH . WPINC . '/js/backbone.min.js';
-		$this->assertTrue( file_exists( $file ) );
+		$this->assertFileExists( $file );
 		$contents = trim( file_get_contents( $file ) );
 		$this->assertFalse( strpos( $contents, 'sourceMappingURL' ), 'Presence of sourceMappingURL' );
 	}
diff --git a/tests/phpunit/tests/multisite/ms-files-rewriting.php b/tests/phpunit/tests/multisite/ms-files-rewriting.php
index 38be416aac..62d666bd64 100644
--- a/tests/phpunit/tests/multisite/ms-files-rewriting.php
+++ b/tests/phpunit/tests/multisite/ms-files-rewriting.php
@@ -76,14 +76,14 @@ class Tests_Multisite_MS_Files_Rewriting extends WP_UnitTestCase {
 		wpmu_delete_blog( $blog_id, true );
 
 		// The file on the main site should still exist. The file on the deleted site should not.
-		$this->assertTrue( file_exists( $file1['file'] ) );
-		$this->assertFalse( file_exists( $file2['file'] ) );
+		$this->assertFileExists( $file1['file'] );
+		$this->assertFileNotExists( $file2['file'] );
 
 		wpmu_delete_blog( $blog_id, true );
 
 		// The file on the main site should still exist. The file on the deleted site should not.
-		$this->assertTrue( file_exists( $file1['file'] ) );
-		$this->assertFalse( file_exists( $file2['file'] ) );
+		$this->assertFileExists( $file1['file'] );
+		$this->assertFileNotExists( $file2['file'] );
 	}
 }
 
diff --git a/tests/phpunit/tests/multisite/site.php b/tests/phpunit/tests/multisite/site.php
index 33d47a22b5..7387d95d98 100644
--- a/tests/phpunit/tests/multisite/site.php
+++ b/tests/phpunit/tests/multisite/site.php
@@ -285,14 +285,14 @@ class Tests_Multisite_Site extends WP_UnitTestCase {
 		wpmu_delete_blog( $blog_id, true );
 
 		// The file on the main site should still exist. The file on the deleted site should not.
-		$this->assertTrue( file_exists( $file1['file'] ) );
-		$this->assertFalse( file_exists( $file2['file'] ) );
+		$this->assertFileExists( $file1['file'] );
+		$this->assertFileNotExists( $file2['file'] );
 
 		wpmu_delete_blog( $blog_id, true );
 
 		// The file on the main site should still exist. The file on the deleted site should not.
-		$this->assertTrue( file_exists( $file1['file'] ) );
-		$this->assertFalse( file_exists( $file2['file'] ) );
+		$this->assertFileExists( $file1['file'] );
+		$this->assertFileNotExists( $file2['file'] );
 	}
 
 	function test_wpmu_update_blogs_date() {
diff --git a/tests/phpunit/tests/theme.php b/tests/phpunit/tests/theme.php
index 9d8d57182d..a9136d1dfd 100644
--- a/tests/phpunit/tests/theme.php
+++ b/tests/phpunit/tests/theme.php
@@ -210,7 +210,7 @@ class Tests_Theme extends WP_UnitTestCase {
 		$wp_theme = wp_get_theme( $this->theme_slug );
 		$this->assertNotEmpty( $wp_theme->get('License') );
 		$path_to_style_css = $wp_theme->get_theme_root() . '/' . $wp_theme->get_stylesheet() . '/style.css';
-		$this->assertTrue( file_exists( $path_to_style_css ) );
+		$this->assertFileExists( $path_to_style_css );
 		$theme_data = get_theme_data( $path_to_style_css );
 		$this->assertArrayHasKey( 'License', $theme_data );
 		$this->assertArrayNotHasKey( 'Not a Valid Key', $theme_data );
diff --git a/tests/phpunit/tests/theme/themeDir.php b/tests/phpunit/tests/theme/themeDir.php
index ab43eec4da..ef6e64c210 100644
--- a/tests/phpunit/tests/theme/themeDir.php
+++ b/tests/phpunit/tests/theme/themeDir.php
@@ -246,8 +246,8 @@ class Tests_Theme_ThemeDir extends WP_UnitTestCase {
 		@mkdir( WP_CONTENT_DIR . '/themes/foo' );
 		@mkdir( WP_CONTENT_DIR . '/themes/foo-themes' );
 
-		$this->assertTrue( file_exists( WP_CONTENT_DIR . '/themes/foo' ) );
-		$this->assertTrue( file_exists( WP_CONTENT_DIR . '/themes/foo-themes') );
+		$this->assertFileExists( WP_CONTENT_DIR . '/themes/foo' );
+		$this->assertFileExists( WP_CONTENT_DIR . '/themes/foo-themes' );
 
 		register_theme_directory( '/' );