EDD Git Download Updater class/process-file.php update for pantheon compatibility. This whole gist (disregarding the <?php ?> tags) should replace the EDD_GIT_Download_Updater_Process_File::unzip() function.

trs-edd-gdu-fix.php

<?php
	/**
	 * "Iteratively" copy files to replace rename function
	 *
	 * This is used for Pantheon and Pressable compatibility
	 * 
	 * @param string $src
	 * @param string $dst
	 * @return boolean $new_file
	 */
	public function iterative_copy($source,$dest) { 

		$ret = mkdir($dest); 

		foreach ( $iterator = new \RecursiveIteratorIterator( 
			new \RecursiveDirectoryIterator($source,
			\RecursiveDirectoryIterator::SKIP_DOTS), \RecursiveIteratorIterator::SELF_FIRST) 
		as $item ) {
				if ($item->isDir()) {
					mkdir($dest . DIRECTORY_SEPARATOR . $iterator->getSubPathName());
				} else {
					copy($item, $dest . DIRECTORY_SEPARATOR . $iterator->getSubPathName());
				}
		}

		unlink($source);

		return $ret;
	}

	/*
	 * Unzip our file into a new temporary folder.
	 *
	 * @param string $zip_path
	 * @since 1.0
	 * @return string $new_dir
	 */
	public function unzip( $zip_path ) {
		if ( is_dir( trailingslashit( $this->tmp_dir . $this->folder_name ) ) ) {
			$this->remove_dir( trailingslashit( $this->tmp_dir . $this->folder_name ) );
		}
		$zip = new ZipArchive();
		$zip->open( $zip_path );
		$zip->extractTo( $this->tmp_dir );
		$zip->close();
		$this->set_sub_dir( $this->tmp_dir );

		// old
		$new_dir = rename( $this->tmp_dir . $this->sub_dir, $this->tmp_dir . $this->folder_name );

		// pantheon compatibility
		// pressable compatibility
		// If $new_dir is false due to a fail in rename()
		if( ! $new_dir ) {
			$new_dir = $this->iterative_copy( $this->tmp_dir . $this->sub_dir, $this->tmp_dir . $this->folder_name );
		}
		if ( ! $new_dir ) {
			return false;
		}
		$new_dir = $this->tmp_dir . $this->folder_name;
		$this->set_sub_dir( $this->tmp_dir );
		unlink( $this->tmp_dir . $this->file_name );
		
		/**
		 * Allow developers to add an action once the .zip file has been extracted.
		 *
		 * @since 1.3
		 * @param string $new_dir   The new directory.
		 * @param string $repo_name The name of the Git repository.
		 */
		do_action( 'edd_git_zip_extracted', $new_dir, $this->repo_name );

		return $new_dir;
	}
?>