Check that fields aren't restricted to certain entity types

Good point; I never thought of that!

Patch looks good, though could you run it through Coder module please to fix docblock formatting, constants, and whitespace please?

Also:

+++ b/field_tools.module
@@ -95,3 +95,16 @@ function field_tools_menu() {
+ * @param string|array $field_info

Let's just say this always has to be a $field_info. It's cleaner to not have mixed purpose params, and it's no great burden on a caller to have to load the field info first; callers will usually have it.

Your docblock still wasn't laid out quite right; I've committed it with a bit of tidying up.

For reference, this is how docblocks should be laid out (at least last time I checked coding standards... which do change!)

/**
 * Helper function to determine whether a field can be attached an entity type.
 *
 * Certain fields like comment_body are restricted to certain entity types.
 *
 * @param string $entity_type
 *  The entity type to check.
 * @param array $field_info
 *  The field info to check.
 *
 * @return boolean
 *  Whether the field can be attached to the entity type.
 */

- #1604768 by tedbow: Fixed lack of check that fields aren't restricted to certain entity types.

Thanks again for the patch!