fix: missing define_variable for export declarations

[xc2]

Summary

fixes: #5994

Require Documentation?

• No
• Yes, the corresponding rspack-website PR is __

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[h-a-n-a]

Thank you!

[ahabhgk]

seems export default function Mod() {} will have the same problem?

[xc2]

seems export default function Mod() {} will have the same problem?

ExportDefaultDeclaration case is covered here:

rspack/crates/rspack_plugin_javascript/src/visitors/dependency/parser/walk_block_pre.rs

Lines 28 to 30 in ffd46f0

	ModuleDecl::ExportDefaultDecl(decl) => {
	self.block_pre_walk_export_default_declaration(decl)
	}

rspack/crates/rspack_plugin_javascript/src/visitors/dependency/parser/walk_block_pre.rs

Lines 93 to 123 in ffd46f0

	fn block_pre_walk_export_default_declaration(&mut self, decl: &ExportDefaultDecl) {
	// FIXME: webpack use `self.pre_walk_statement(decl.decl)`
	match &decl.decl {
	DefaultDecl::Class(expr) => {
	if let Some(ident) = &expr.ident {
	self.define_variable(ident.sym.to_string())
	}
	}
	DefaultDecl::Fn(expr) => {
	if let Some(ident) = &expr.ident {
	self.define_variable(ident.sym.to_string())
	}
	}
	DefaultDecl::TsInterfaceDecl(_) => unreachable!(),
	}
	// FIXME: webpack use `self.block_pre_walk_statement(decl.decl)`
	// match &decl.decl {
	// DefaultDecl::Class(expr) => {
	// if let Some(ident) = &expr.ident {
	// self.define_variable(ident.sym.to_string())
	// }
	// }
	// DefaultDecl::Fn(expr) => {
	// if let Some(ident) = &expr.ident {
	// self.define_variable(ident.sym.to_string())
	// }
	// }
	// DefaultDecl::TsInterfaceDecl(_) => unreachable!(),
	// }
	}

[xc2]

test case added: #6024