refactor(markdown): emit continuation indent as structural CST node

crates/biome_markdown_formatter/src/generated.rs

@@ -121,6 +121,44 @@ impl IntoFormat<MarkdownFormatContext> for biome_markdown_syntax::MdBulletListIt
         )
     }
 }
+impl FormatRule<biome_markdown_syntax::MdContinuationIndent>
+    for crate::markdown::auxiliary::continuation_indent::FormatMdContinuationIndent
+{
+    type Context = MarkdownFormatContext;
+    #[inline(always)]
+    fn fmt(
+        &self,
+        node: &biome_markdown_syntax::MdContinuationIndent,
+        f: &mut MarkdownFormatter,
+    ) -> FormatResult<()> {
+        FormatNodeRule::<biome_markdown_syntax::MdContinuationIndent>::fmt(self, node, f)
+    }
+}
+impl AsFormat<MarkdownFormatContext> for biome_markdown_syntax::MdContinuationIndent {
+    type Format<'a> = FormatRefWithRule<
+        'a,
+        biome_markdown_syntax::MdContinuationIndent,
+        crate::markdown::auxiliary::continuation_indent::FormatMdContinuationIndent,
+    >;
+    fn format(&self) -> Self::Format<'_> {
+        FormatRefWithRule::new(
+            self,
+            crate::markdown::auxiliary::continuation_indent::FormatMdContinuationIndent::default(),
+        )
+    }
+}
+impl IntoFormat<MarkdownFormatContext> for biome_markdown_syntax::MdContinuationIndent {
+    type Format = FormatOwnedWithRule<
+        biome_markdown_syntax::MdContinuationIndent,
+        crate::markdown::auxiliary::continuation_indent::FormatMdContinuationIndent,
+    >;
+    fn into_format(self) -> Self::Format {
+        FormatOwnedWithRule::new(
+            self,
+            crate::markdown::auxiliary::continuation_indent::FormatMdContinuationIndent::default(),
+        )
+    }
+}
 impl FormatRule<biome_markdown_syntax::MdDocument>
     for crate::markdown::auxiliary::document::FormatMdDocument
 {

crates/biome_markdown_formatter/src/markdown/any/leaf_block.rs

@@ -9,6 +9,7 @@ impl FormatRule<AnyMdLeafBlock> for FormatAnyMdLeafBlock {
     fn fmt(&self, node: &AnyMdLeafBlock, f: &mut MarkdownFormatter) -> FormatResult<()> {
         match node {
             AnyMdLeafBlock::AnyMdCodeBlock(node) => node.format().fmt(f),
+            AnyMdLeafBlock::MdContinuationIndent(node) => node.format().fmt(f),
             AnyMdLeafBlock::MdHeader(node) => node.format().fmt(f),
             AnyMdLeafBlock::MdHtmlBlock(node) => node.format().fmt(f),
             AnyMdLeafBlock::MdLinkReferenceDefinition(node) => node.format().fmt(f),

crates/biome_markdown_formatter/src/markdown/auxiliary/continuation_indent.rs

@@ -0,0 +1,14 @@
+use crate::prelude::*;
+use biome_markdown_syntax::MdContinuationIndent;
+use biome_rowan::AstNode;
+#[derive(Debug, Clone, Default)]
+pub(crate) struct FormatMdContinuationIndent;
+impl FormatNodeRule<MdContinuationIndent> for FormatMdContinuationIndent {
+    fn fmt_fields(
+        &self,
+        node: &MdContinuationIndent,
+        f: &mut MarkdownFormatter,
+    ) -> FormatResult<()> {
+        format_verbatim_node(node.syntax()).fmt(f)
+    }
+}

crates/biome_markdown_formatter/src/markdown/auxiliary/mod.rs

@@ -3,6 +3,7 @@
 pub(crate) mod autolink;
 pub(crate) mod bullet;
 pub(crate) mod bullet_list_item;
+pub(crate) mod continuation_indent;
 pub(crate) mod document;
 pub(crate) mod entity_reference;
 pub(crate) mod fenced_code_block;

crates/biome_markdown_parser/src/syntax/list.rs

@@ -2041,10 +2041,13 @@ fn check_continuation_indent(
                 };
             }
 
-            // Consume the structural indent as trivia so that block
-            // detection (at_bullet_list_item, etc.) works on the
-            // de-indented content. See §5.2 continuation lines.
-            p.skip_line_indent(state.required_indent);
+            // Emit the indentation for a continuation line inside a list item
+            // as an explicit MdContinuationIndent node so it appears in the
+            // CST rather than as skipped trivia. See CommonMark §5.2:
+            // https://spec.commonmark.org/0.31.2/#list-items
+            let ci_m = p.start();
+            p.emit_line_indent(state.required_indent);
+            ci_m.complete(p, MD_CONTINUATION_INDENT);
             p.set_virtual_line_start();
 
             return ContinuationResult {

crates/biome_markdown_parser/src/to_html.rs

@@ -44,11 +44,11 @@
 
 use biome_markdown_syntax::{
     AnyMdBlock, AnyMdBulletListMember, AnyMdCodeBlock, AnyMdInline, AnyMdLeafBlock,
-    MarkdownLanguage, MdAutolink, MdBlockList, MdBullet, MdBulletListItem, MdDocument,
-    MdEntityReference, MdFencedCodeBlock, MdHardLine, MdHeader, MdHtmlBlock, MdIndentCodeBlock,
-    MdInlineCode, MdInlineEmphasis, MdInlineHtml, MdInlineImage, MdInlineItalic, MdInlineItemList,
-    MdInlineLink, MdLinkDestination, MdLinkLabel, MdLinkReferenceDefinition, MdLinkTitle,
-    MdOrderedListItem, MdParagraph, MdQuote, MdReferenceImage, MdReferenceLink,
+    MarkdownLanguage, MdAutolink, MdBlockList, MdBullet, MdBulletListItem, MdContinuationIndent,
+    MdDocument, MdEntityReference, MdFencedCodeBlock, MdHardLine, MdHeader, MdHtmlBlock,
+    MdIndentCodeBlock, MdInlineCode, MdInlineEmphasis, MdInlineHtml, MdInlineImage, MdInlineItalic,
+    MdInlineItemList, MdInlineLink, MdLinkDestination, MdLinkLabel, MdLinkReferenceDefinition,
+    MdLinkTitle, MdOrderedListItem, MdParagraph, MdQuote, MdReferenceImage, MdReferenceLink,
     MdReferenceLinkLabel, MdSetextHeader, MdSoftBreak, MdTextual, MdThematicBreakBlock,
 };
 use biome_rowan::{AstNode, AstNodeList, Direction, SyntaxNode, TextRange, WalkEvent};
@@ -526,6 +526,11 @@ impl<'a> HtmlRenderer<'a> {
     }
 
     fn enter(&mut self, node: SyntaxNode<MarkdownLanguage>) {
+        if MdContinuationIndent::cast(node.clone()).is_some() {
+            self.opaque_depth = Some(self.depth);
+            return;
+        }
+
         if MdInlineItemList::cast(node.clone()).is_some()
             && self
                 .suppressed_inline_nodes
@@ -622,7 +627,16 @@ impl<'a> HtmlRenderer<'a> {
 
         if let Some(bullet) = MdBullet::cast(node.clone()) {
             let list_is_tight = self.list_stack.last().is_some_and(|state| state.is_tight);
-            let blocks: Vec<_> = bullet.content().iter().collect();
+            let blocks: Vec<_> = bullet
+                .content()
+                .iter()
+                .filter(|b| {
+                    !matches!(
+                        b,
+                        AnyMdBlock::AnyMdLeafBlock(AnyMdLeafBlock::MdContinuationIndent(_),)
+                    )
+                })
+                .collect();
             let item_has_blank_line = blocks
                 .windows(2)
                 .any(|pair| is_newline_block(&pair[0]) && is_newline_block(&pair[1]));
@@ -1173,12 +1187,12 @@ fn render_fenced_code_block(
 ) {
     out.push_str("<pre><code");
 
-    // Determine the fence indentation from the explicit indent slot
+    // Determine the fence indentation from the explicit indent slot.
+    // The indent list only contains the fence's own 0-3 spaces;
+    // list/quote indent is handled separately via container_indent.
     let fence_leading_indent = indent_list_width(&code.indent());
     let container_indent = list_indent + quote_indent;
-    let fence_indent = fence_leading_indent
-        .saturating_sub(container_indent)
-        .min(MAX_BLOCK_PREFIX_INDENT);
+    let fence_indent = fence_leading_indent.min(MAX_BLOCK_PREFIX_INDENT);
     let content_indent = container_indent + fence_indent;
 
     // Get info string (language) - process escapes
@@ -1749,11 +1763,13 @@ fn is_paragraph_block(block: &AnyMdBlock) -> bool {
     )
 }
 
-/// Check if a block is a newline (produces no output).
+/// Check if a block is a newline or continuation indent (produces no output).
 fn is_newline_block(block: &AnyMdBlock) -> bool {
     matches!(
         block,
-        AnyMdBlock::AnyMdLeafBlock(AnyMdLeafBlock::MdNewline(_))
+        AnyMdBlock::AnyMdLeafBlock(
+            AnyMdLeafBlock::MdNewline(_) | AnyMdLeafBlock::MdContinuationIndent(_),
+        )
     )
 }
 

crates/biome_markdown_parser/tests/md_test_suite/ok/fenced_code_in_list.md.snap

@@ -45,10 +45,20 @@ MdDocument {
                         MdNewline {
                             value_token: NEWLINE@6..7 "\n" [] [],
                         },
+                        MdContinuationIndent {
+                            indent: MdIndentTokenList [
+                                MdIndentToken {
+                                    md_indent_char_token: MD_INDENT_CHAR@7..8 " " [] [],
+                                },
+                                MdIndentToken {
+                                    md_indent_char_token: MD_INDENT_CHAR@8..9 " " [] [],
+                                },
+                            ],
+                        },
                         MdFencedCodeBlock {
                             indent: MdIndentTokenList [
                                 MdIndentToken {
-                                    md_indent_char_token: MD_INDENT_CHAR@7..10 " " [Whitespace(" "), Whitespace(" ")] [],
+                                    md_indent_char_token: MD_INDENT_CHAR@9..10 " " [] [],
                                 },
                                 MdIndentToken {
                                     md_indent_char_token: MD_INDENT_CHAR@10..11 " " [] [],
@@ -135,10 +145,16 @@ MdDocument {
               1: (empty)
             1: MD_NEWLINE@6..7
               0: NEWLINE@6..7 "\n" [] []
-            2: MD_FENCED_CODE_BLOCK@7..41
-              0: MD_INDENT_TOKEN_LIST@7..11
-                0: MD_INDENT_TOKEN@7..10
-                  0: MD_INDENT_CHAR@7..10 " " [Whitespace(" "), Whitespace(" ")] []
+            2: MD_CONTINUATION_INDENT@7..9
+              0: MD_INDENT_TOKEN_LIST@7..9
+                0: MD_INDENT_TOKEN@7..8
+                  0: MD_INDENT_CHAR@7..8 " " [] []
+                1: MD_INDENT_TOKEN@8..9
+                  0: MD_INDENT_CHAR@8..9 " " [] []
+            3: MD_FENCED_CODE_BLOCK@9..41
+              0: MD_INDENT_TOKEN_LIST@9..11
+                0: MD_INDENT_TOKEN@9..10
+                  0: MD_INDENT_CHAR@9..10 " " [] []
                 1: MD_INDENT_TOKEN@10..11
                   0: MD_INDENT_CHAR@10..11 " " [] []
               1: TRIPLE_BACKTICK@11..14 "```" [] []

crates/biome_markdown_parser/tests/md_test_suite/ok/html_block_in_list.md.snap

@@ -215,10 +215,20 @@ MdDocument {
                         MdNewline {
                             value_token: NEWLINE@355..356 "\n" [] [],
                         },
+                        MdContinuationIndent {
+                            indent: MdIndentTokenList [
+                                MdIndentToken {
+                                    md_indent_char_token: MD_INDENT_CHAR@356..357 " " [] [],
+                                },
+                                MdIndentToken {
+                                    md_indent_char_token: MD_INDENT_CHAR@357..358 " " [] [],
+                                },
+                            ],
+                        },
                         MdParagraph {
                             list: MdInlineItemList [
                                 MdTextual {
-                                    value_token: MD_TEXTUAL_LITERAL@356..467 "NOTE: the shape of the JSON is considered experimental, and the shape of the JSON might change in the future." [Whitespace(" "), Whitespace(" ")] [],
+                                    value_token: MD_TEXTUAL_LITERAL@358..467 "NOTE: the shape of the JSON is considered experimental, and the shape of the JSON might change in the future." [] [],
                                 },
                                 MdTextual {
                                     value_token: MD_TEXTUAL_LITERAL@467..468 "\n" [] [],
@@ -229,11 +239,21 @@ MdDocument {
                         MdNewline {
                             value_token: NEWLINE@468..469 "\n" [] [],
                         },
+                        MdContinuationIndent {
+                            indent: MdIndentTokenList [
+                                MdIndentToken {
+                                    md_indent_char_token: MD_INDENT_CHAR@469..470 " " [] [],
+                                },
+                                MdIndentToken {
+                                    md_indent_char_token: MD_INDENT_CHAR@470..471 " " [] [],
+                                },
+                            ],
+                        },
                         MdHtmlBlock {
                             indent: MdIndentTokenList [],
                             content: MdInlineItemList [
                                 MdTextual {
-                                    value_token: MD_TEXTUAL_LITERAL@469..472 "<" [Whitespace(" "), Whitespace(" ")] [],
+                                    value_token: MD_TEXTUAL_LITERAL@471..472 "<" [] [],
                                 },
                                 MdTextual {
                                     value_token: MD_TEXTUAL_LITERAL@472..479 "details" [] [],
@@ -2302,20 +2322,32 @@ MdDocument {
               1: (empty)
             1: MD_NEWLINE@355..356
               0: NEWLINE@355..356 "\n" [] []
-            2: MD_PARAGRAPH@356..468
-              0: MD_INLINE_ITEM_LIST@356..468
-                0: MD_TEXTUAL@356..467
-                  0: MD_TEXTUAL_LITERAL@356..467 "NOTE: the shape of the JSON is considered experimental, and the shape of the JSON might change in the future." [Whitespace(" "), Whitespace(" ")] []
+            2: MD_CONTINUATION_INDENT@356..358
+              0: MD_INDENT_TOKEN_LIST@356..358
+                0: MD_INDENT_TOKEN@356..357
+                  0: MD_INDENT_CHAR@356..357 " " [] []
+                1: MD_INDENT_TOKEN@357..358
+                  0: MD_INDENT_CHAR@357..358 " " [] []
+            3: MD_PARAGRAPH@358..468
+              0: MD_INLINE_ITEM_LIST@358..468
+                0: MD_TEXTUAL@358..467
+                  0: MD_TEXTUAL_LITERAL@358..467 "NOTE: the shape of the JSON is considered experimental, and the shape of the JSON might change in the future." [] []
                 1: MD_TEXTUAL@467..468
                   0: MD_TEXTUAL_LITERAL@467..468 "\n" [] []
               1: (empty)
-            3: MD_NEWLINE@468..469
+            4: MD_NEWLINE@468..469
               0: NEWLINE@468..469 "\n" [] []
-            4: MD_HTML_BLOCK@469..2001
-              0: MD_INDENT_TOKEN_LIST@469..469
-              1: MD_INLINE_ITEM_LIST@469..2001
-                0: MD_TEXTUAL@469..472
-                  0: MD_TEXTUAL_LITERAL@469..472 "<" [Whitespace(" "), Whitespace(" ")] []
+            5: MD_CONTINUATION_INDENT@469..471
+              0: MD_INDENT_TOKEN_LIST@469..471
+                0: MD_INDENT_TOKEN@469..470
+                  0: MD_INDENT_CHAR@469..470 " " [] []
+                1: MD_INDENT_TOKEN@470..471
+                  0: MD_INDENT_CHAR@470..471 " " [] []
+            6: MD_HTML_BLOCK@471..2001
+              0: MD_INDENT_TOKEN_LIST@471..471
+              1: MD_INLINE_ITEM_LIST@471..2001
+                0: MD_TEXTUAL@471..472
+                  0: MD_TEXTUAL_LITERAL@471..472 "<" [] []
                 1: MD_TEXTUAL@472..479
                   0: MD_TEXTUAL_LITERAL@472..479 "details" [] []
                 2: MD_TEXTUAL@479..480

crates/biome_markdown_parser/tests/md_test_suite/ok/list_continuation_edge_cases.md.snap

@@ -353,10 +353,20 @@ MdDocument {
                                 },
                             ],
                         },
+                        MdContinuationIndent {
+                            indent: MdIndentTokenList [
+                                MdIndentToken {
+                                    md_indent_char_token: MD_INDENT_CHAR@323..324 " " [] [],
+                                },
+                                MdIndentToken {
+                                    md_indent_char_token: MD_INDENT_CHAR@324..325 " " [] [],
+                                },
+                            ],
+                        },
                         MdParagraph {
                             list: MdInlineItemList [
                                 MdTextual {
-                                    value_token: MD_TEXTUAL_LITERAL@323..365 "outer continuation at parent indentation" [Whitespace(" "), Whitespace(" ")] [],
+                                    value_token: MD_TEXTUAL_LITERAL@325..365 "outer continuation at parent indentation" [] [],
                                 },
                                 MdTextual {
                                     value_token: MD_TEXTUAL_LITERAL@365..366 "\n" [] [],
@@ -691,14 +701,20 @@ MdDocument {
                         7: MD_TEXTUAL@322..323
                           0: MD_TEXTUAL_LITERAL@322..323 "\n" [] []
                       1: (empty)
-            2: MD_PARAGRAPH@323..366
-              0: MD_INLINE_ITEM_LIST@323..366
-                0: MD_TEXTUAL@323..365
-                  0: MD_TEXTUAL_LITERAL@323..365 "outer continuation at parent indentation" [Whitespace(" "), Whitespace(" ")] []
+            2: MD_CONTINUATION_INDENT@323..325
+              0: MD_INDENT_TOKEN_LIST@323..325
+                0: MD_INDENT_TOKEN@323..324
+                  0: MD_INDENT_CHAR@323..324 " " [] []
+                1: MD_INDENT_TOKEN@324..325
+                  0: MD_INDENT_CHAR@324..325 " " [] []
+            3: MD_PARAGRAPH@325..366
+              0: MD_INLINE_ITEM_LIST@325..366
+                0: MD_TEXTUAL@325..365
+                  0: MD_TEXTUAL_LITERAL@325..365 "outer continuation at parent indentation" [] []
                 1: MD_TEXTUAL@365..366
                   0: MD_TEXTUAL_LITERAL@365..366 "\n" [] []
               1: (empty)
-            3: MD_NEWLINE@366..367
+            4: MD_NEWLINE@366..367
               0: NEWLINE@366..367 "\n" [] []
         1: MD_BULLET@367..385
           0: MD_LIST_MARKER_PREFIX@367..368