refactor(markdown): deduplicate shared helper functions

crates/biome_markdown_parser/src/syntax/fenced_code_block.rs

@@ -23,6 +23,7 @@
 //! that can be used for syntax highlighting.
 
 use crate::parser::MarkdownParser;
+use crate::token_source::find_line_start;
 use biome_markdown_syntax::{T, kind::MarkdownSyntaxKind::*};
 use biome_parser::{
     Parser,
@@ -108,26 +109,6 @@ fn bump_fence(p: &mut MarkdownParser, is_tilde_fence: bool) {
     }
 }
 
-/// Find the start position of the current line in the source text.
-///
-/// Given a slice of text before the current position, finds the byte offset
-/// where the current line begins (after the last newline, handling CRLF).
-fn find_line_start(before: &str) -> usize {
-    let last_newline_pos = before.rfind(['\n', '\r']);
-    match last_newline_pos {
-        Some(pos) => {
-            let bytes = before.as_bytes();
-            // Handle CRLF: if we found \r and next char is \n, skip both
-            if bytes.get(pos) == Some(&b'\r') && bytes.get(pos + 1) == Some(&b'\n') {
-                pos + 2
-            } else {
-                pos + 1
-            }
-        }
-        None => 0,
-    }
-}
-
 /// Detect a code fence at the start of a string.
 ///
 /// Per CommonMark §4.5: "A code fence is a sequence of at least three

crates/biome_markdown_parser/src/syntax/list.rs

@@ -56,7 +56,7 @@ use crate::syntax::thematic_break_block::parse_thematic_break_block;
 use crate::syntax::with_virtual_line_start;
 use crate::syntax::{
     INDENT_CODE_BLOCK_SPACES, MAX_BLOCK_PREFIX_INDENT, TAB_STOP_SPACES, at_block_interrupt,
-    at_indent_code_block, is_paragraph_like,
+    at_indent_code_block, is_paragraph_like, is_whitespace_only,
 };
 
 /// Tokens that start a new block (used for recovery)
@@ -205,10 +205,6 @@ fn emit_list_post_marker_space(p: &mut MarkdownParser) -> bool {
     }
 }
 
-fn is_whitespace_only(text: &str) -> bool {
-    !text.is_empty() && text.chars().all(|c| c == ' ' || c == '\t')
-}
-
 /// Check if the remaining content forms a thematic break pattern.
 ///
 /// Per CommonMark §4.1, a thematic break is 3 or more matching characters
@@ -838,7 +834,11 @@ impl ParseNodeList for OrderedList {
     type Kind = MarkdownSyntaxKind;
     type Parser<'source> = MarkdownParser<'source>;
 
-    const LIST_KIND: Self::Kind = MD_BULLET_LIST; // Reuse bullet list node structure
+    // The Markdown grammar defines a single MdBulletList node kind for both
+    // bullet and ordered lists — the marker type distinguishes them, not the
+    // CST node kind. This keeps the grammar simpler and avoids duplicating
+    // the entire list/item node hierarchy.
+    const LIST_KIND: Self::Kind = MD_BULLET_LIST;
 
     fn parse_element(&mut self, p: &mut Self::Parser<'_>) -> ParsedSyntax {
         parse_list_element_common(

crates/biome_markdown_parser/src/syntax/mod.rs

@@ -1780,7 +1780,7 @@ fn is_empty_list_item(p: &mut MarkdownParser) -> bool {
     is_empty
 }
 
-fn is_whitespace_only(text: &str) -> bool {
+pub(crate) fn is_whitespace_only(text: &str) -> bool {
     !text.is_empty() && text.chars().all(|c| c == ' ' || c == '\t')
 }
 

crates/biome_markdown_parser/src/syntax/quote.rs

@@ -43,6 +43,7 @@ use crate::syntax::parse_any_block_with_indent_code_policy;
 use crate::syntax::parse_error::quote_nesting_too_deep;
 use crate::syntax::{
     INDENT_CODE_BLOCK_SPACES, MAX_BLOCK_PREFIX_INDENT, TAB_STOP_SPACES, is_paragraph_like,
+    is_whitespace_only,
 };
 
 /// Check if we're at the start of a block quote (`>`).
@@ -197,11 +198,6 @@ fn emit_quote_pre_marker_indents(p: &mut MarkdownParser) {
     indent_list_m.complete(p, MD_QUOTE_INDENT_LIST);
 }
 
-/// Check if text contains only spaces and tabs.
-fn is_whitespace_only(text: &str) -> bool {
-    !text.is_empty() && text.chars().all(|c| c == ' ' || c == '\t')
-}
-
 /// Calculate indent width accounting for tab expansion (CommonMark §2.2).
 fn calculate_indent_width(text: &str) -> usize {
     text.chars()

crates/biome_markdown_parser/src/token_source.rs

@@ -11,7 +11,7 @@ use biome_rowan::{TextRange, TriviaPieceKind};
 ///
 /// Given a slice of text, finds the byte offset where the current line begins
 /// (after the last newline, handling CRLF).
-fn find_line_start(before: &str) -> usize {
+pub(crate) fn find_line_start(before: &str) -> usize {
     let last_newline_pos = before.rfind(['\n', '\r']);
     match last_newline_pos {
         Some(pos) => {