Enderman held block not fully updated from old block id system

An Enderman holding a dirt block can be summoned using the command

summon enderman ~ ~ ~ {carried:"minecraft:dirt"}

As you would expect, this summons an Enderman holding a dirt block (see also MC-94027). However if you try this command:

/testfor @e {carried:"minecraft:dirt"}

the enderman will not be found by the command.

This is because the block type is stored using the old id system (dirt is stored as 3) and because the tag is a short you have to append s:

/testfor @e {carried:3s}