The import attributes proposal changed the keyword from assert to with, after that it was already been implemented and shipped in some browsers. Thus, there are some implementations that only support the assert syntax and others that only support the with syntax.
For this reason, the import attributes, JSON modules and CSS modules are duplicated to use both keywords: | with keyword | assert keyword | |:----------------------|:---------------------------| | ./import-attributes | ./import-assertions | | ./json-module | ./json-module-assertions | | ./css-module | ./css-module-assertions |
All changes in one folder should be reflected in the corresponding folder, because the two syntaxes have the same semantics.
The web compatibility of removing the assert keyword is being investigated. If it will be deemed feasible, it will be removed from the proposal and the assert tests can be deleted.