move package parsing into package_resolve

doc/api/esm.md

@@ -202,16 +202,7 @@ The algorithm to resolve an ES module specifier is provided through _ESM_RESOLVE
 >    1. Let _resolvedURL_ be the URL resolution of _specifier_ to _parentURL_.
 >    1. Return the result of **PATH_RESOLVE**(_resolvedURL_).
 > 1. Note: _specifier_ is now a bare specifier.
-> 1. Let _packageName_ be _undefined_.
-> 1. Let _packagePath_ be _undefined_.
-> 1. If _name_ does not start with _"@"_ then,
->    1. Set _packageName_ to the substring of _specifier_ until the first _"/"_ separator or the end of the string.
-> 1. If _name_ starts with _"@"_ then,
->    1. If _name_ does not contain a _"/"_ separator then,
->       1. Throw a _Invalid Package Name_ error.
->    1. Set _packageName_ to the substring of _specifier_ until the second _"/"_ separator or the end of the string.
-> 1. Let _packagePath_ be the substring of _specifier_ from the position at the length of _packageName_ plus one, if any.
-> 1. Return the result of **PACKAGE_RESOLVE**(_packageName_, _packagePath_, _parentURL_), or propagating any errors thrown.
+> 1. Return the result of **PACKAGE_RESOLVE**(_specifier_).
 
 **PATH_RESOLVE**(_resolvedURL_)
 > 1. If the file at _resolvedURL_ exists then,
@@ -221,9 +212,19 @@ The algorithm to resolve an ES module specifier is provided through _ESM_RESOLVE
 >    1. Return _packageMainURL_.
 > 1. Throw a _Module Not Found_ error.
 
-**PACKAGE_RESOLVE**(_packageName_, _packagePath_, _parentURL_)
-> 1. Assert: _packagePath_ is either empty, or a path without a leading separator.
+**PACKAGE_RESOLVE**(_packageSpecifier_)
+> 1. Assert: _packageSpecifier_ is a valid bare specifier.
+> 1. Let _packageName_ be _undefined_.
+> 1. Let _packagePath_ be _undefined_.
+> 1. If _packageSpecifier_ does not start with _"@"_ then,
+>    1. Set _packageName_ to the substring of _packageSpecifier_ until the first _"/"_ separator or the end of the string.
+> 1. If _packageSpecifier_ starts with _"@"_ then,
+>    1. If _packageSpecifier_ does not contain a _"/"_ separator then,
+>       1. Throw a _Invalid Package Name_ error.
+>    1. Set _packageName_ to the substring of _packageSpecifier_ until the second _"/"_ separator or the end of the string.
+> 1. Let _packagePath_ be the substring of _packageSpecifier_ from the position at the length of _packageName_ plus one, if any.
 > 1. Assert: _packageName_ is a valid package name or scoped package name.
+> 1. Assert: _packagePath_ is either empty, or a path without a leading separator.
 > 1. Note: Further package name encoding validations can be added here.
 > 1. If _packagePath_ is empty and _packageName_ is a Node.js builtin module then,
 >    1. Return _"node:${packageName}"_.