Plugin Directory: Fix PHP warnings when building plugin ZIPs and checking block plugins.

When an SVN export fails but the error details aren't available, the code
tried to read them anyway, triggering warnings. Add a fallback so a
generic message is used instead.

Also fixes a typo in a constant name that would have caused a fatal error
when a plugin directory turned out to be empty.

git-svn-id: https://meta.svn.wordpress.org/sites/trunk@14773 74240141-8908-4e6f-9713-ba540dce6ec7

Author: obenland

wordpress.org/public_html/wp-content/plugins/plugin-directory/cli/class-block-plugin-checker.php

@@ -248,8 +248,8 @@ function export_plugin( $svn_url ) {
 			$this->record_result(
 				__FUNCTION__,
 				'error',
-				sprintf( __( 'Error fetching repository %s: %s', 'wporg-plugins' ), $svn_url, $export['errors'][0]['error_code'] ),
-				$export['errors']
+				sprintf( __( 'Error fetching repository %s: %s', 'wporg-plugins' ), $svn_url, $export['errors'][0]['error_code'] ?? 'unknown error' ),
+				$export['errors'] ?? array()
 			);
 			return false;
 		}

wordpress.org/public_html/wp-content/plugins/plugin-directory/zip/class-builder.php

@@ -395,15 +395,15 @@ protected function export_plugin() {
 			$res                          = SVN::export( $this->plugin_version_svn_url, $build_dir, $svn_params );
 		}
 		if ( ! $res['result'] ) {
-			throw new Exception( __METHOD__ . ': ' . $res['errors'][0]['error_message'], 404 );
+			throw new Exception( __METHOD__ . ': ' . ( $res['errors'][0]['error_message'] ?? 'unknown error' ), 404 );
 		}
 
 		// Store the SVN revision that's been used for the ZIP in a property for later.
 		$this->plugins_revision = $res['revision'];
 
 		// Verify that the specified plugin zip will contain files.
 		if ( ! array_diff( scandir( $this->tmp_build_dir ), array( '.', '..' ) ) ) {
-			throw new Exception( ___METHOD__ . ': No files exist in the plugin directory', 404 );
+			throw new Exception( __METHOD__ . ': No files exist in the plugin directory', 404 );
 		}
 
 		// Cleanup any symlinks that shouldn't be there