tools: support VDOC_SORT=false ./v doc time

cmd/tools/vdoc/html.v

@@ -394,9 +394,13 @@ fn doc_node_html(dn doc.DocNode, link string, head bool, include_examples bool,
 	node_class := if dn.kind == .const_group { ' const' } else { '' }
 	sym_name := get_sym_name(dn)
 	mut deprecated_tags := dn.tags.filter(it.starts_with('deprecated'))
+	if doc.should_sort {
 		deprecated_tags.sort()
+	}
 	mut tags := dn.tags.filter(!it.starts_with('deprecated'))
+	if doc.should_sort {
 		tags.sort()
+	}
 	mut node_id := get_node_id(dn)
 	mut hash_link := if !head { ' <a href="#${node_id}">#</a>' } else { '' }
 	if head && is_module_readme(dn) {

vlib/v/doc/node.v

@@ -1,5 +1,9 @@
 module doc
 
+import os
+
+pub const should_sort = os.getenv_opt('VDOC_SORT') or { 'true' }.bool()
+
 pub fn (nodes []DocNode) find(symname string) !DocNode {
 	for node in nodes {
 		if node.name != symname {
@@ -12,13 +16,17 @@ pub fn (nodes []DocNode) find(symname string) !DocNode {
 
 // sort_by_name sorts the array based on the symbol names.
 pub fn (mut nodes []DocNode) sort_by_name() {
+	if doc.should_sort {
 		nodes.sort_with_compare(compare_nodes_by_name)
 	}
+}
 
 // sort_by_kind sorts the array based on the symbol kind.
 pub fn (mut nodes []DocNode) sort_by_kind() {
+	if doc.should_sort {
 		nodes.sort_with_compare(compare_nodes_by_kind)
 	}
+}
 
 fn compare_nodes_by_kind(a &DocNode, b &DocNode) int {
 	ak := int((*a).kind)

vlib/v/help/common/doc.txt

@@ -39,3 +39,5 @@ For HTML mode:
 For plain text mode:
   -l              Shows the locations of the generated signatures.
   -comments       Includes comments in the output.
+
+Note: set the environment variable `VDOC_SORT` to `false`, to avoid sorting the output.