rumdl_lib/utils/

table_utils.rs

/// Shared table detection and processing utilities for markdown linting rules
///
/// This module provides optimized table detection and processing functionality
/// that can be shared across multiple table-related rules (MD055, MD056, MD058).
use super::blockquote::{parse_blockquote_prefix, strip_blockquote_prefix};

/// How many blockquotes `line` is nested in.
fn blockquote_depth(line: &str) -> usize {
    parse_blockquote_prefix(line).map_or(0, |parsed| parsed.nesting_level)
}

/// Represents a table block in the document
#[derive(Debug, Clone)]
pub struct TableBlock {
    pub start_line: usize,
    pub end_line: usize,
    pub header_line: usize,
    pub delimiter_line: usize,
    pub content_lines: Vec<usize>,
    /// If the table is inside a list item, this contains:
    /// - The list marker prefix for the header line (e.g., "- ", "1. ")
    /// - The content indent (number of spaces for continuation lines)
    pub list_context: Option<ListTableContext>,
}

/// Context information for tables inside list items
#[derive(Debug, Clone)]
pub struct ListTableContext {
    /// The list marker prefix including any leading whitespace (e.g., "- ", "  1. ")
    pub list_prefix: String,
    /// Number of spaces for continuation lines to align with content
    pub content_indent: usize,
}

/// Shared table detection utilities
pub struct TableUtils;

impl TableUtils {
    /// Returns true if the line has at least one unescaped pipe separator outside inline code and
    /// math spans.
    ///
    /// Skips pipes inside backtick code spans (`` `...` ``) and dollar-sign math spans (`$...$`,
    /// `$$...$$`) to avoid false positives from prose like `` `echo a | sed 's/a/b/'` `` or math
    /// like `$|S|$` (absolute value notation).
    ///
    /// Note: a bare `$` that opens a span without a matching closing `$` keeps the scanner in
    /// math mode for the rest of the line, suppressing any subsequent pipes. This is conservative
    /// and means that `$5 | $10`-style price comparisons (without outer pipes) are not detected
    /// as table separators — an accepted trade-off to avoid false positives from real math.
    fn has_unescaped_pipe_outside_spans(text: &str) -> bool {
        let chars: Vec<char> = text.chars().collect();
        let mut i = 0;
        let mut in_code = false;
        let mut code_delim_len = 0usize;
        let mut in_math = false;
        let mut math_delim_len = 0usize;

        while i < chars.len() {
            let ch = chars[i];

            if ch == '\\' && !in_code && !in_math {
                // Skip escaped character (only outside code and math spans —
                // backslashes are literal inside code spans per CommonMark).
                i += if i + 1 < chars.len() { 2 } else { 1 };
                continue;
            }

            if ch == '`' && !in_math {
                let mut run = 1usize;
                while i + run < chars.len() && chars[i + run] == '`' {
                    run += 1;
                }

                if in_code {
                    if run == code_delim_len {
                        in_code = false;
                        code_delim_len = 0;
                    }
                    // Mismatched backtick run inside a code span: consumed but span stays open.
                } else {
                    in_code = true;
                    code_delim_len = run;
                }

                i += run;
                continue;
            }

            if ch == '$' && !in_code {
                let mut run = 1usize;
                while i + run < chars.len() && chars[i + run] == '$' {
                    run += 1;
                }

                if in_math {
                    if run == math_delim_len {
                        in_math = false;
                        math_delim_len = 0;
                    }
                    // Mismatched $-run inside a math span: consumed but span stays open.
                } else {
                    in_math = true;
                    math_delim_len = run;
                }

                i += run;
                continue;
            }

            if ch == '|' && !in_code && !in_math {
                return true;
            }

            i += 1;
        }

        false
    }

    /// Check if a line looks like a potential table row
    /// Flavor-aware form of [`Self::is_potential_table_row`]
    ///
    /// Under Obsidian, a line whose only pipes sit inside wikilink aliases is
    /// prose rather than a table row, so those pipes are masked before the check.
    pub fn is_potential_table_row_with_flavor(line: &str, flavor: crate::config::MarkdownFlavor) -> bool {
        // Masking is the identity without an opener to mask inside, and this runs on
        // every line of the document.
        if flavor == crate::config::MarkdownFlavor::Obsidian && line.contains("[[") {
            return Self::is_potential_table_row(&Self::mask_pipes_in_wikilinks(line));
        }
        Self::is_potential_table_row(line)
    }

    pub fn is_potential_table_row(line: &str) -> bool {
        let trimmed = line.trim();
        if trimmed.is_empty() || !trimmed.contains('|') {
            return false;
        }

        // Skip lines that are clearly not table rows
        // Unordered list items with space or tab after marker
        if trimmed.starts_with("- ")
            || trimmed.starts_with("* ")
            || trimmed.starts_with("+ ")
            || trimmed.starts_with("-\t")
            || trimmed.starts_with("*\t")
            || trimmed.starts_with("+\t")
        {
            return false;
        }

        // Skip ordered list items: digits followed by . or ) then space/tab
        if let Some(first_non_digit) = trimmed.find(|c: char| !c.is_ascii_digit())
            && first_non_digit > 0
        {
            let after_digits = &trimmed[first_non_digit..];
            if after_digits.starts_with(". ")
                || after_digits.starts_with(".\t")
                || after_digits.starts_with(") ")
                || after_digits.starts_with(")\t")
            {
                return false;
            }
        }

        // Skip ATX headings (# through ######)
        if trimmed.starts_with('#') {
            let hash_count = trimmed.bytes().take_while(|&b| b == b'#').count();
            if hash_count <= 6 {
                let after_hashes = &trimmed[hash_count..];
                if after_hashes.is_empty() || after_hashes.starts_with(' ') || after_hashes.starts_with('\t') {
                    return false;
                }
            }
        }

        // For rows without explicit outer pipes, require a real separator outside
        // inline code and math spans to avoid prose/command false positives.
        let has_outer_pipes = trimmed.starts_with('|') && trimmed.ends_with('|');
        if !has_outer_pipes && !Self::has_unescaped_pipe_outside_spans(trimmed) {
            return false;
        }

        // Must have at least 2 parts when split by |
        let parts: Vec<&str> = trimmed.split('|').collect();
        if parts.len() < 2 {
            return false;
        }

        // Check if it looks like a table row by having reasonable content between pipes
        let mut valid_parts = 0;
        let mut total_non_empty_parts = 0;

        for part in &parts {
            let part_trimmed = part.trim();
            // Skip empty parts (from leading/trailing pipes)
            if part_trimmed.is_empty() {
                continue;
            }
            total_non_empty_parts += 1;

            // Count parts that look like table cells (reasonable content, no newlines)
            if !part_trimmed.contains('\n') {
                valid_parts += 1;
            }
        }

        // Check if all non-empty parts are valid (no newlines)
        if total_non_empty_parts > 0 && valid_parts != total_non_empty_parts {
            // Some cells contain newlines, not a valid table row
            return false;
        }

        // GFM allows tables with all empty cells (e.g., |||)
        // These are valid if they have proper table formatting (leading and trailing pipes)
        if total_non_empty_parts == 0 {
            // Empty cells are only valid with proper pipe formatting
            return trimmed.starts_with('|') && trimmed.ends_with('|') && parts.len() >= 3;
        }

        // GFM allows single-column tables, so >= 1 valid part is enough
        // when the line has proper table formatting (pipes)
        if trimmed.starts_with('|') && trimmed.ends_with('|') {
            // Properly formatted table row with pipes on both ends
            valid_parts >= 1
        } else {
            // For rows without proper pipe formatting, require at least 2 cells
            valid_parts >= 2
        }
    }

    /// Check if a line is a table delimiter row (e.g., |---|---|)
    pub fn is_delimiter_row(line: &str) -> bool {
        let trimmed = line.trim();
        if !trimmed.contains('|') || !trimmed.contains('-') {
            return false;
        }

        // Split by pipes and check each part
        let parts: Vec<&str> = trimmed.split('|').collect();
        let mut valid_delimiter_parts = 0;
        let mut total_non_empty_parts = 0;

        for part in &parts {
            let part_trimmed = part.trim();
            if part_trimmed.is_empty() {
                continue; // Skip empty parts from leading/trailing pipes
            }

            total_non_empty_parts += 1;

            // Check if this part looks like a delimiter (contains dashes and optionally colons)
            if part_trimmed.chars().all(|c| c == '-' || c == ':' || c.is_whitespace()) && part_trimmed.contains('-') {
                valid_delimiter_parts += 1;
            }
        }

        // All non-empty parts must be valid delimiters, and there must be at least one
        total_non_empty_parts > 0 && valid_delimiter_parts == total_non_empty_parts
    }

    /// Find all table blocks in the content with optimized detection
    /// This version accepts code_blocks and code_spans directly for use during LintContext construction
    pub fn find_table_blocks_with_code_info(
        content: &str,
        code_blocks: &[(usize, usize)],
        code_spans: &[crate::lint_context::CodeSpan],
        html_comment_ranges: &[crate::utils::skip_context::ByteRange],
        flavor: crate::config::MarkdownFlavor,
    ) -> Vec<TableBlock> {
        let lines: Vec<&str> = content.lines().collect();
        let mut tables = Vec::new();
        let mut i = 0;

        // Pre-compute line positions for efficient code block checking.
        // `str::lines()` strips the trailing `\r` from CRLF lines, so advancing by
        // `line.len() + 1` undercounts by one byte per CRLF line; the positions then
        // drift out of sync with the raw byte offsets that `code_blocks` uses, which
        // can misclassify a later table header as being inside a code block. Walk the
        // actual line terminator (`\n` or `\r\n`) from the raw bytes instead.
        let mut line_positions = Vec::with_capacity(lines.len());
        let content_bytes = content.as_bytes();
        let mut pos = 0;
        for line in &lines {
            line_positions.push(pos);
            pos += line.len();
            if content_bytes.get(pos) == Some(&b'\r') {
                pos += 1;
            }
            if content_bytes.get(pos) == Some(&b'\n') {
                pos += 1;
            }
        }

        // Stack of active list content indents for continuation table tracking.
        // Supports nested lists: when a child list is seen, we push; when we
        // dedent past a level, we pop back to the enclosing list.
        let mut list_indent_stack: Vec<usize> = Vec::new();

        while i < lines.len() {
            // Skip lines in code blocks, code spans, or HTML comments
            let line_start = line_positions[i];
            let in_code =
                crate::utils::code_block_utils::CodeBlockUtils::is_in_code_block_or_span(code_blocks, line_start) || {
                    // Binary search on sorted code spans
                    let idx = code_spans.partition_point(|span| span.byte_offset <= line_start);
                    idx > 0 && line_start < code_spans[idx - 1].byte_end
                };
            let in_html_comment = {
                // Binary search on sorted HTML comment ranges
                let idx = html_comment_ranges.partition_point(|range| range.start <= line_start);
                idx > 0 && line_start < html_comment_ranges[idx - 1].end
            };

            if in_code || in_html_comment {
                i += 1;
                continue;
            }

            // Strip blockquote prefix for table detection
            let line_content = strip_blockquote_prefix(lines[i]);

            // Update active list tracking
            let (list_prefix, list_content, content_indent) = Self::extract_list_prefix(line_content);
            if !list_prefix.is_empty() {
                // Line has a list marker. Pop any deeper/equal levels, then push this one.
                while list_indent_stack.last().is_some_and(|&top| top >= content_indent) {
                    list_indent_stack.pop();
                }
                list_indent_stack.push(content_indent);
            } else if !line_content.trim().is_empty() {
                // Non-blank line without a marker: pop any levels we've dedented past
                let leading = line_content.len() - line_content.trim_start().len();
                while list_indent_stack.last().is_some_and(|&top| leading < top) {
                    list_indent_stack.pop();
                }
            }
            // Blank lines keep the stack unchanged (blank lines don't end list items)

            // Check if this is a list item that contains a table row on the same line,
            // or a continuation table indented under an active list item
            let (is_same_line_list_table, effective_content) =
                if !list_prefix.is_empty() && Self::is_potential_table_row_content(list_content, flavor) {
                    (true, list_content)
                } else {
                    (false, line_content)
                };

            // Detect continuation list tables: no marker on this line, but indented
            // under an active list item (e.g., "- Text\n  | h1 | h2 |")
            let continuation_indent = if !is_same_line_list_table && list_prefix.is_empty() {
                let leading = line_content.len() - line_content.trim_start().len();
                // Find the deepest list level this line is indented under
                list_indent_stack
                    .iter()
                    .rev()
                    .find(|&&indent| leading >= indent)
                    .copied()
            } else {
                None
            };

            let is_continuation_list_table = continuation_indent.is_some()
                && {
                    let indent = continuation_indent.unwrap();
                    let leading = line_content.len() - line_content.trim_start().len();
                    // Per CommonMark, 4+ spaces beyond content indent is a code block
                    leading < indent + 4
                }
                && Self::is_potential_table_row_with_flavor(effective_content, flavor);

            let is_any_list_table = is_same_line_list_table || is_continuation_list_table;

            // For continuation list tables, use the matched list indent
            let effective_content_indent = if is_same_line_list_table {
                content_indent
            } else if is_continuation_list_table {
                continuation_indent.unwrap()
            } else {
                0
            };

            // Look for potential table start
            if is_any_list_table || Self::is_potential_table_row_with_flavor(effective_content, flavor) {
                // For list tables (same-line or continuation), check indented continuation lines
                // For regular tables, check the next line directly
                let (next_line_content, delimiter_has_valid_indent) = if i + 1 < lines.len() {
                    let next_raw = strip_blockquote_prefix(lines[i + 1]);
                    if is_any_list_table {
                        // Verify the delimiter line has proper indentation
                        let leading_spaces = next_raw.len() - next_raw.trim_start().len();
                        if leading_spaces >= effective_content_indent {
                            // Has proper indentation, strip it and check as delimiter
                            (
                                Self::strip_list_continuation_indent(next_raw, effective_content_indent),
                                true,
                            )
                        } else {
                            // Not enough indentation - not a list table
                            (next_raw, false)
                        }
                    } else {
                        (next_raw, true)
                    }
                } else {
                    ("", true)
                };

                // For list tables, only accept if delimiter has valid indentation
                let effective_is_list_table = is_any_list_table && delimiter_has_valid_indent;

                if i + 1 < lines.len() && Self::is_delimiter_row(next_line_content) {
                    // Found a table! Find its end
                    let table_start = i;
                    let header_line = i;
                    let delimiter_line = i + 1;
                    let mut table_end = i + 1; // Include the delimiter row
                    let mut content_lines = Vec::new();

                    // Continue while we have table rows
                    let table_depth = blockquote_depth(lines[i]);
                    let mut j = i + 2;
                    while j < lines.len() {
                        let line = lines[j];
                        // Strip blockquote prefix for checking
                        let raw_content = strip_blockquote_prefix(line);

                        // For list tables, strip expected indentation
                        let line_content = if effective_is_list_table {
                            Self::strip_list_continuation_indent(raw_content, effective_content_indent)
                        } else {
                            raw_content
                        };

                        if line_content.trim().is_empty() {
                            // Empty line ends the table
                            break;
                        }

                        // For list tables, the continuation line must have proper indentation
                        if effective_is_list_table {
                            let leading_spaces = raw_content.len() - raw_content.trim_start().len();
                            if leading_spaces < effective_content_indent {
                                // Not enough indentation - end of table
                                break;
                            }
                        }

                        // A row belongs to the container the table is in, and
                        // every other non-blank line is a row, with or without
                        // pipes, until another block starts. The Obsidian
                        // flavor keeps requiring a pipe outside a wikilink, so
                        // a paragraph holding a wikilink alias stays prose.
                        if blockquote_depth(line) != table_depth
                            || Self::starts_block_after_table(line_content)
                            || (flavor == crate::config::MarkdownFlavor::Obsidian
                                && !Self::is_potential_table_row_with_flavor(line_content, flavor))
                        {
                            break;
                        }
                        content_lines.push(j);
                        table_end = j;
                        j += 1;
                    }

                    let list_context = if effective_is_list_table {
                        if is_same_line_list_table {
                            // Same-line: prefix is the actual list marker (e.g., "- ")
                            Some(ListTableContext {
                                list_prefix: list_prefix.to_string(),
                                content_indent: effective_content_indent,
                            })
                        } else {
                            // Continuation: prefix is the indentation spaces
                            Some(ListTableContext {
                                list_prefix: " ".repeat(effective_content_indent),
                                content_indent: effective_content_indent,
                            })
                        }
                    } else {
                        None
                    };

                    tables.push(TableBlock {
                        start_line: table_start,
                        end_line: table_end,
                        header_line,
                        delimiter_line,
                        content_lines,
                        list_context,
                    });
                    i = table_end + 1;
                } else {
                    i += 1;
                }
            } else {
                i += 1;
            }
        }

        tables
    }

    /// Whether `line`, a line after a table's rows inside the table's own
    /// container, starts a block and so ends the table. GFM ends a table only
    /// at a blank line or the start of another block, so any other line is a
    /// row, pipes or not.
    ///
    /// Only the openers markdown-rs and pulldown-cmark agree on count. Where
    /// they disagree (a line indented four columns, `#` followed by a tab, a
    /// type-7 HTML tag, a footnote label with a space in it) the line is taken
    /// as a row: a rule then leaves it alone rather than rewrite it, or insert
    /// a blank line before it, on the strength of one parser's reading.
    ///
    /// A colon fence is the one exception. GFM has no such block, but every
    /// syntax that writes `:::` (Pandoc and Quarto divs, MyST, Azure DevOps,
    /// Docusaurus and VitePress admonitions, generic directives) opens or
    /// closes a container there, and a table row holding only colons is not
    /// something anyone writes on purpose.
    fn starts_block_after_table(line: &str) -> bool {
        let indent = line.bytes().take_while(|&b| b == b' ').count();
        if indent >= 4 || line[indent..].starts_with('\t') {
            return false;
        }
        let text = line[indent..].trim_end();
        let bytes = text.as_bytes();
        let Some(&first) = bytes.first() else {
            return false;
        };
        let space_or_end = |at: usize| bytes.get(at).is_none_or(|&b| b == b' ' || b == b'\t');
        match first {
            b'>' => true,
            b'-' | b'*' | b'+' if space_or_end(1) => true,
            b'-' | b'*' | b'_' => crate::utils::thematic_break::is_thematic_break(text),
            b'0'..=b'9' => {
                let digits = bytes.iter().take_while(|b| b.is_ascii_digit()).count();
                digits <= 9 && matches!(bytes.get(digits), Some(b'.' | b')')) && space_or_end(digits + 1)
            }
            b'#' => {
                let hashes = bytes.iter().take_while(|&&b| b == b'#').count();
                hashes <= 6 && bytes.get(hashes).is_none_or(|&b| b == b' ')
            }
            b'`' | b'~' | b':' => bytes.iter().take_while(|&&b| b == first).count() >= 3,
            b'<' => {
                crate::utils::html_block::opens_untagged_html_block(text)
                    || crate::utils::html_block::parse_html_block_start(text).is_some_and(|(tag, _)| {
                        !crate::utils::html_block::NON_SPEC_BLOCK_ELEMENTS.contains(&tag.as_str())
                    })
            }
            b'[' => text
                .strip_prefix("[^")
                .and_then(|rest| rest.split_once("]:"))
                .is_some_and(|(label, _)| {
                    !label.is_empty() && !label.contains(|c: char| c.is_whitespace() || c == ']')
                }),
            _ => false,
        }
    }

    /// Strip list continuation indentation from a line.
    /// For lines that are continuations of a list item's content, strip the expected indent.
    fn strip_list_continuation_indent(line: &str, expected_indent: usize) -> &str {
        let bytes = line.as_bytes();
        let mut spaces = 0;

        for &b in bytes {
            if b == b' ' {
                spaces += 1;
            } else if b == b'\t' {
                // Tab counts as up to 4 spaces, rounding up to next multiple of 4
                spaces = (spaces / 4 + 1) * 4;
            } else {
                break;
            }

            if spaces >= expected_indent {
                break;
            }
        }

        // Strip at most expected_indent characters
        let strip_count = spaces.min(expected_indent).min(line.len());
        // Count actual bytes to strip (handling tabs)
        let mut byte_count = 0;
        let mut counted_spaces = 0;
        for &b in bytes {
            if counted_spaces >= strip_count {
                break;
            }
            if b == b' ' {
                counted_spaces += 1;
                byte_count += 1;
            } else if b == b'\t' {
                counted_spaces = (counted_spaces / 4 + 1) * 4;
                byte_count += 1;
            } else {
                break;
            }
        }

        &line[byte_count..]
    }

    /// Find all table blocks in the content with optimized detection
    /// This is a backward-compatible wrapper that accepts LintContext
    pub fn find_table_blocks(content: &str, ctx: &crate::lint_context::LintContext) -> Vec<TableBlock> {
        Self::find_table_blocks_with_code_info(
            content,
            &ctx.code_blocks,
            &ctx.code_spans(),
            ctx.html_comment_ranges(),
            ctx.flavor,
        )
    }

    /// Count the number of cells in a table row
    pub fn count_cells(row: &str) -> usize {
        Self::count_cells_with_flavor(row, crate::config::MarkdownFlavor::Standard)
    }

    /// Count the number of cells in a table row with flavor-specific behavior
    ///
    /// Pipes inside code spans are treated as content, not cell delimiters.
    ///
    /// This function strips blockquote prefixes before counting cells, so it works
    /// correctly for tables inside blockquotes.
    pub fn count_cells_with_flavor(row: &str, flavor: crate::config::MarkdownFlavor) -> usize {
        // Strip blockquote prefix if present before counting cells
        let (_, content) = Self::extract_blockquote_prefix(row);
        Self::split_table_row_with_flavor(content, flavor).len()
    }

    /// Count the number of consecutive backslashes immediately preceding `pos` in `chars`.
    fn count_preceding_backslashes(chars: &[char], pos: usize) -> usize {
        let mut count = 0;
        let mut k = pos;
        while k > 0 {
            k -= 1;
            if chars[k] == '\\' {
                count += 1;
            } else {
                break;
            }
        }
        count
    }

    /// Locate the inline code spans in `chars` as half-open char ranges covering
    /// the opening delimiter, the content and the closing delimiter.
    ///
    /// Backticks preceded by an odd number of backslashes are escaped (literal text)
    /// and do not open or close code spans. An even number of backslashes means the
    /// backslashes themselves are escaped, so the backtick is a real delimiter. A run
    /// of backticks with no matching closing run of the same length is literal text,
    /// and scanning resumes just after it.
    ///
    /// This is the single definition of a code span for table parsing: both pipe
    /// masking and wikilink detection read it, so they cannot disagree about where
    /// code starts and ends.
    fn inline_code_spans(chars: &[char]) -> Vec<(usize, usize)> {
        let mut spans = Vec::new();
        let mut i = 0;

        while i < chars.len() {
            if chars[i] != '`' {
                i += 1;
                continue;
            }

            // A backtick preceded by an odd number of backslashes is escaped
            if Self::count_preceding_backslashes(chars, i) % 2 != 0 {
                i += 1;
                continue;
            }

            // Count consecutive backticks at start
            let start = i;
            let mut backtick_count = 0;
            while i < chars.len() && chars[i] == '`' {
                backtick_count += 1;
                i += 1;
            }

            // Look for a closing run of exactly the same length. Per CommonMark,
            // backslash escapes do NOT work inside code spans -- all characters
            // including backslashes are literal -- so no escape check applies here.
            let mut j = i;
            while j < chars.len() {
                if chars[j] == '`' {
                    let mut close_count = 0;
                    while j < chars.len() && chars[j] == '`' {
                        close_count += 1;
                        j += 1;
                    }

                    if close_count == backtick_count {
                        spans.push((start, j));
                        i = j;
                        break;
                    }
                    // Run of a different length: keep searching (j is already past it)
                } else {
                    j += 1;
                }
            }
            // With no matching closing run the opener is literal text; `i` already
            // sits just past it, so a later backtick can still open a span.
        }

        spans
    }

    /// Mask pipes inside inline code blocks with a placeholder character.
    ///
    /// The mask is the same byte width as what it replaces, so offsets into the
    /// masked string still address the original text.
    pub fn mask_pipes_in_inline_code(text: &str) -> String {
        if !text.contains('`') {
            return text.to_string();
        }

        let chars: Vec<char> = text.chars().collect();
        let spans = Self::inline_code_spans(&chars);
        if spans.is_empty() {
            return text.to_string();
        }

        let mut result = String::with_capacity(text.len());
        let mut cursor = 0;
        for (start, end) in spans {
            result.extend(chars[cursor..start].iter());
            // The delimiters are backticks, so masking every pipe across the whole
            // span leaves them untouched and only rewrites the content.
            for &ch in &chars[start..end] {
                result.push(if ch == '|' { '_' } else { ch });
            }
            cursor = end;
        }
        result.extend(chars[cursor..].iter());

        result
    }

    /// Mask pipes inside wikilink aliases for accurate table cell parsing
    ///
    /// In Obsidian, `[[Target|Label]]` renders `Label` as a link to `Target`, so
    /// the pipe separates the two halves of one link rather than two table cells.
    /// Only a pipe between `[[` and a closing `]]` on the same line is masked.
    ///
    /// Two shapes are deliberately left as prose, because reading them as a link
    /// would merge cells in a table that is already well formed and so would report
    /// a column-count mismatch against a document that has none:
    ///
    /// - Brackets inside an inline code span. Code binds tighter than links, so
    ///   ``` `[[` | mid | `]]` ``` is three cells of prose, not one cell with a link.
    /// - A blank link target. `[[ | ]]` and `[[|Label]]` name no note, so the
    ///   brackets are prose that happens to straddle a cell divider.
    ///
    /// The mask is the same byte width as what it replaces, so offsets into the
    /// masked string still address the original text.
    pub fn mask_pipes_in_wikilinks(text: &str) -> String {
        // Without both halves of an opener and a pipe to hide there is nothing to do,
        // and this runs over every line of an Obsidian document.
        if !text.contains("[[") || !text.contains('|') {
            return text.to_string();
        }

        let chars: Vec<char> = text.chars().collect();
        let code_spans = Self::inline_code_spans(&chars);
        let code_span_at = |pos: usize| code_spans.iter().find(|&&(s, e)| pos >= s && pos < e).copied();

        let mut result = String::with_capacity(text.len());
        let mut i = 0;

        while i < chars.len() {
            // Copy a code span through untouched; nothing inside it is link syntax.
            if let Some((_, end)) = code_span_at(i) {
                result.extend(chars[i..end].iter());
                i = end;
                continue;
            }

            if chars[i] == '['
                && i + 1 < chars.len()
                && chars[i + 1] == '['
                && let Some(close) = Self::wikilink_close(&chars, &code_spans, i)
            {
                result.push_str("[[");
                for &ch in &chars[i + 2..close] {
                    if ch == '|' {
                        result.push('_'); // Mask pipe with underscore
                    } else {
                        result.push(ch);
                    }
                }
                result.push_str("]]");
                i = close + 2;
                continue;
            }

            result.push(chars[i]);
            i += 1;
        }

        result
    }

    /// Find the `]]` closing the wikilink opened by the `[[` at `open`, or `None`
    /// when the brackets do not delimit one.
    ///
    /// `code_spans` are the ranges from [`Self::inline_code_spans`]; brackets and
    /// pipes inside one are content, so the scan steps over them whole.
    fn wikilink_close(chars: &[char], code_spans: &[(usize, usize)], open: usize) -> Option<usize> {
        let mut j = open + 2;
        let mut first_pipe = None;

        while j + 1 < chars.len() {
            if let Some(&(_, end)) = code_spans.iter().find(|&&(s, _)| s == j) {
                j = end;
                continue;
            }

            if chars[j] == ']' && chars[j + 1] == ']' {
                // The half before the pipe names the note the link points at, so a
                // blank one means these brackets are prose that happens to straddle
                // a cell divider rather than a link holding one.
                if let Some(pipe) = first_pipe
                    && chars[open + 2..pipe].iter().all(|c| c.is_whitespace())
                {
                    return None;
                }
                return Some(j);
            }

            // A wikilink does not span a nested "[["
            if chars[j] == '[' && chars[j + 1] == '[' {
                return None;
            }

            if chars[j] == '|' && first_pipe.is_none() {
                first_pipe = Some(j);
            }

            j += 1;
        }

        None
    }

    /// Mask escaped pipes for accurate table cell parsing
    ///
    /// In GFM tables, escape handling happens BEFORE cell boundary detection:
    /// - `\|` → escaped pipe → masked (stays as cell content)
    /// - `\\|` → escaped backslash + pipe → NOT masked (pipe is a delimiter)
    ///
    /// This function only handles escaped pipes. Pipes inside inline code spans
    /// are handled separately by `mask_pipes_in_inline_code`.
    pub fn mask_pipes_for_table_parsing(text: &str) -> String {
        let mut result = String::new();
        let chars: Vec<char> = text.chars().collect();
        let mut i = 0;

        while i < chars.len() {
            if chars[i] == '\\' {
                if i + 1 < chars.len() && chars[i + 1] == '\\' {
                    // Escaped backslash: \\ → push both and continue
                    // The next character (if it's a pipe) will be a real delimiter
                    result.push('\\');
                    result.push('\\');
                    i += 2;
                } else if i + 1 < chars.len() && chars[i + 1] == '|' {
                    // Escaped pipe: \| → mask the pipe
                    result.push('\\');
                    result.push('_'); // Mask the pipe
                    i += 2;
                } else {
                    // Single backslash not followed by \ or | → just push it
                    result.push(chars[i]);
                    i += 1;
                }
            } else {
                result.push(chars[i]);
                i += 1;
            }
        }

        result
    }

    /// Split a table row into individual cell contents with flavor-specific behavior.
    ///
    /// Returns a Vec of cell content strings (not trimmed - preserves original spacing).
    /// This is the foundation for both cell counting and cell content extraction.
    ///
    /// Pipes inside code spans are treated as content, not cell delimiters.
    pub fn split_table_row_with_flavor(row: &str, flavor: crate::config::MarkdownFlavor) -> Vec<String> {
        let trimmed = row.trim();

        if !trimmed.contains('|') {
            return Vec::new();
        }

        // First, mask escaped pipes (same for all flavors)
        let masked = Self::mask_pipes_for_table_parsing(trimmed);

        // Mask pipes inside inline code for all flavors
        let mut final_masked = Self::mask_pipes_in_inline_code(&masked);

        // In Obsidian, a pipe inside [[Target|Label]] separates the link from its
        // alias rather than one cell from the next
        if flavor == crate::config::MarkdownFlavor::Obsidian {
            final_masked = Self::mask_pipes_in_wikilinks(&final_masked);
        }

        let has_leading = final_masked.starts_with('|');
        let has_trailing = final_masked.ends_with('|');

        let mut masked_content = final_masked.as_str();
        let mut orig_content = trimmed;

        if has_leading {
            masked_content = &masked_content[1..];
            orig_content = &orig_content[1..];
        }

        // Track whether we actually strip a trailing pipe
        let stripped_trailing = has_trailing && !masked_content.is_empty();
        if stripped_trailing {
            masked_content = &masked_content[..masked_content.len() - 1];
            orig_content = &orig_content[..orig_content.len() - 1];
        }

        // Handle edge cases for degenerate inputs
        if masked_content.is_empty() {
            if stripped_trailing {
                // "||" case: two pipes with empty content between = one empty cell
                return vec![String::new()];
            } else {
                // "|" case: single pipe, not a valid table row
                return Vec::new();
            }
        }

        let masked_parts: Vec<&str> = masked_content.split('|').collect();
        let mut cells = Vec::new();
        let mut pos = 0;

        for masked_cell in masked_parts {
            let cell_len = masked_cell.len();
            let orig_cell = if pos + cell_len <= orig_content.len() {
                &orig_content[pos..pos + cell_len]
            } else {
                masked_cell
            };
            cells.push(orig_cell.to_string());
            pos += cell_len + 1; // +1 for the pipe delimiter
        }

        cells
    }

    /// Split a table row into individual cell contents using Standard/GFM behavior.
    pub fn split_table_row(row: &str) -> Vec<String> {
        Self::split_table_row_with_flavor(row, crate::config::MarkdownFlavor::Standard)
    }

    /// Whether a row ends in a delimiter rather than an escaped cell-content pipe.
    pub(crate) fn has_unescaped_trailing_pipe(line: &str) -> bool {
        let bytes = line.trim_end().as_bytes();
        if bytes.last() != Some(&b'|') {
            return false;
        }
        bytes[..bytes.len() - 1]
            .iter()
            .rev()
            .take_while(|&&byte| byte == b'\\')
            .count()
            % 2
            == 0
    }

    /// Determine the pipe style of a table row
    ///
    /// Handles tables inside blockquotes by stripping the blockquote prefix
    /// before analyzing the pipe style.
    pub fn determine_pipe_style(line: &str) -> Option<&'static str> {
        // Strip blockquote prefix if present before analyzing pipe style
        let content = strip_blockquote_prefix(line);
        let trimmed = content.trim();
        if !trimmed.contains('|') {
            return None;
        }

        let has_leading = trimmed.starts_with('|');
        let has_trailing = Self::has_unescaped_trailing_pipe(trimmed);

        match (has_leading, has_trailing) {
            (true, true) => Some("leading_and_trailing"),
            (true, false) => Some("leading_only"),
            (false, true) => Some("trailing_only"),
            (false, false) => Some("no_leading_or_trailing"),
        }
    }

    /// Extract blockquote prefix from a line, returning (prefix, content).
    ///
    /// This is useful for stripping the prefix before processing, then restoring it after.
    /// For example: `"> | H1 | H2 |"` returns `("> ", "| H1 | H2 |")`.
    pub fn extract_blockquote_prefix(line: &str) -> (&str, &str) {
        // Find where the actual content starts (after blockquote markers and spaces)
        let bytes = line.as_bytes();
        let mut pos = 0;

        // Skip leading whitespace (indent before blockquote marker)
        while pos < bytes.len() && (bytes[pos] == b' ' || bytes[pos] == b'\t') {
            pos += 1;
        }

        // If no blockquote marker, return empty prefix
        if pos >= bytes.len() || bytes[pos] != b'>' {
            return ("", line);
        }

        // Skip all blockquote markers and spaces
        while pos < bytes.len() {
            if bytes[pos] == b'>' {
                pos += 1;
                // Skip optional space after >
                if pos < bytes.len() && bytes[pos] == b' ' {
                    pos += 1;
                }
            } else if bytes[pos] == b' ' || bytes[pos] == b'\t' {
                pos += 1;
            } else {
                break;
            }
        }

        // Split at the position where content starts
        (&line[..pos], &line[pos..])
    }

    /// Extract list marker prefix from a line, returning (prefix, content, content_indent).
    ///
    /// This handles unordered list markers (`-`, `*`, `+`) and ordered list markers (`1.`, `10)`, etc.)
    /// Returns:
    /// - prefix: The list marker including any leading whitespace and trailing space (e.g., "- ", "  1. ")
    /// - content: The content after the list marker
    /// - content_indent: The number of spaces needed for continuation lines to align with content
    ///
    /// For example:
    /// - `"- | H1 | H2 |"` returns `("- ", "| H1 | H2 |", 2)`
    /// - `"1. | H1 | H2 |"` returns `("1. ", "| H1 | H2 |", 3)`
    /// - `"  - table"` returns `("  - ", "table", 4)`
    ///
    /// Returns `("", line, 0)` if the line doesn't start with a list marker.
    pub fn extract_list_prefix(line: &str) -> (&str, &str, usize) {
        let bytes = line.as_bytes();

        // Skip leading whitespace
        let leading_spaces = bytes.iter().take_while(|&&b| b == b' ' || b == b'\t').count();
        let mut pos = leading_spaces;

        if pos >= bytes.len() {
            return ("", line, 0);
        }

        // Check for unordered list marker: -, *, +
        if matches!(bytes[pos], b'-' | b'*' | b'+') {
            pos += 1;

            // Must be followed by space or tab (or end of line for marker-only lines)
            if pos >= bytes.len() || bytes[pos] == b' ' || bytes[pos] == b'\t' {
                // Skip the space after marker if present
                if pos < bytes.len() && (bytes[pos] == b' ' || bytes[pos] == b'\t') {
                    pos += 1;
                }
                let content_indent = pos;
                return (&line[..pos], &line[pos..], content_indent);
            }
            // Not a list marker (e.g., "-word" or "--")
            return ("", line, 0);
        }

        // Check for ordered list marker: digits followed by . or ) then space
        if bytes[pos].is_ascii_digit() {
            let digit_start = pos;
            while pos < bytes.len() && bytes[pos].is_ascii_digit() {
                pos += 1;
            }

            // Must have at least one digit
            if pos > digit_start && pos < bytes.len() {
                // Check for . or ) followed by space/tab
                if bytes[pos] == b'.' || bytes[pos] == b')' {
                    pos += 1;
                    if pos >= bytes.len() || bytes[pos] == b' ' || bytes[pos] == b'\t' {
                        // Skip the space after marker if present
                        if pos < bytes.len() && (bytes[pos] == b' ' || bytes[pos] == b'\t') {
                            pos += 1;
                        }
                        let content_indent = pos;
                        return (&line[..pos], &line[pos..], content_indent);
                    }
                }
            }
        }

        ("", line, 0)
    }

    /// Extract the table row content from a line, stripping any list/blockquote prefix.
    ///
    /// This is useful for processing table rows that may be inside list items or blockquotes.
    /// The line_index indicates which line of the table this is (0 = header, 1 = delimiter, etc.)
    pub fn extract_table_row_content<'a>(line: &'a str, table_block: &TableBlock, line_index: usize) -> &'a str {
        // First strip blockquote prefix
        let (_, after_blockquote) = Self::extract_blockquote_prefix(line);

        // Then handle list prefix if present
        if let Some(ref list_ctx) = table_block.list_context {
            if line_index == 0 {
                // Header line: strip list prefix (handles both markers and indentation)
                after_blockquote
                    .strip_prefix(&list_ctx.list_prefix)
                    .unwrap_or_else(|| Self::extract_list_prefix(after_blockquote).1)
            } else {
                // Continuation lines: strip indentation
                Self::strip_list_continuation_indent(after_blockquote, list_ctx.content_indent)
            }
        } else {
            after_blockquote
        }
    }

    /// Check if the content after a list marker looks like a table row.
    /// This is used to detect tables that start on the same line as a list marker.
    pub fn is_list_item_with_table_row(line: &str, flavor: crate::config::MarkdownFlavor) -> bool {
        let (prefix, content, _) = Self::extract_list_prefix(line);
        if prefix.is_empty() {
            return false;
        }

        // Check if the content after the list marker is a table row
        // It must start with | (proper table format within a list)
        let trimmed = content.trim();
        if !trimmed.starts_with('|') {
            return false;
        }

        // Use our table row detection on the content
        Self::is_potential_table_row_content(content, flavor)
    }

    /// Internal helper: Check if content (without list/blockquote prefix) looks like a table row.
    fn is_potential_table_row_content(content: &str, flavor: crate::config::MarkdownFlavor) -> bool {
        Self::is_potential_table_row_with_flavor(content, flavor)
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::lint_context::LintContext;

    #[test]
    fn test_is_potential_table_row() {
        // Basic valid table rows
        assert!(TableUtils::is_potential_table_row("| Header 1 | Header 2 |"));
        assert!(TableUtils::is_potential_table_row("| Cell 1 | Cell 2 |"));
        assert!(TableUtils::is_potential_table_row("Cell 1 | Cell 2"));
        assert!(TableUtils::is_potential_table_row("| Cell |")); // Single-column tables are valid in GFM

        // Multiple cells
        assert!(TableUtils::is_potential_table_row("| A | B | C | D | E |"));

        // With whitespace
        assert!(TableUtils::is_potential_table_row("  | Indented | Table |  "));
        assert!(TableUtils::is_potential_table_row("| Spaces | Around |"));

        // Not table rows
        assert!(!TableUtils::is_potential_table_row("- List item"));
        assert!(!TableUtils::is_potential_table_row("* Another list"));
        assert!(!TableUtils::is_potential_table_row("+ Plus list"));
        assert!(!TableUtils::is_potential_table_row("Regular text"));
        assert!(!TableUtils::is_potential_table_row(""));
        assert!(!TableUtils::is_potential_table_row("   "));

        // Code blocks
        assert!(!TableUtils::is_potential_table_row("`code with | pipe`"));
        assert!(!TableUtils::is_potential_table_row("``multiple | backticks``"));
        assert!(!TableUtils::is_potential_table_row("Use ``a|b`` in prose"));
        assert!(TableUtils::is_potential_table_row("| `fenced` | Uses ``` and ~~~ |"));
        assert!(TableUtils::is_potential_table_row("`!foo && bar` | `(!foo) && bar`"));
        assert!(!TableUtils::is_potential_table_row("`echo a | sed 's/a/b/'`"));

        // Math spans: pipes inside $...$ are not table separators
        assert!(!TableUtils::is_potential_table_row(
            "Text with $|S|$ math notation here."
        ));
        assert!(!TableUtils::is_potential_table_row(
            "Size $|S|$ was even, check $|T|$ too."
        ));
        assert!(!TableUtils::is_potential_table_row("Display $$|A| + |B|$$ math here."));
        // Math pipe in cell with outer pipes is still a table row
        assert!(TableUtils::is_potential_table_row("| cell with $|S|$ math |"));
        // Pipe after fully closed math spans is still detected
        assert!(TableUtils::is_potential_table_row("$a$ | $b$"));
        assert!(TableUtils::is_potential_table_row("$f(x)$ and $g(x)$ | result"));
        // $5 | $10 style price comparisons are suppressed as a deliberate trade-off:
        // the leading $ opens a math span, consuming the pipe. Tables with bare dollar
        // amounts should use outer pipes (| $5 | $10 |) to be correctly detected.
        assert!(!TableUtils::is_potential_table_row("$5 | $10"));

        // Single pipe not enough
        assert!(!TableUtils::is_potential_table_row("Just one |"));
        assert!(!TableUtils::is_potential_table_row("| Just one"));

        // Very long cells are valid in tables (no length limit for cell content)
        let long_cell = "a".repeat(150);
        assert!(TableUtils::is_potential_table_row(&format!("| {long_cell} | b |")));

        // Cells with newlines
        assert!(!TableUtils::is_potential_table_row("| Cell with\nnewline | Other |"));

        // Empty cells (Issue #129)
        assert!(TableUtils::is_potential_table_row("|||")); // Two empty cells
        assert!(TableUtils::is_potential_table_row("||||")); // Three empty cells
        assert!(TableUtils::is_potential_table_row("| | |")); // Two empty cells with spaces
    }

    #[test]
    fn test_list_items_with_pipes_not_table_rows() {
        // Ordered list items should NOT be detected as table rows
        assert!(!TableUtils::is_potential_table_row("1. Item with | pipe"));
        assert!(!TableUtils::is_potential_table_row("10. Item with | pipe"));
        assert!(!TableUtils::is_potential_table_row("999. Item with | pipe"));
        assert!(!TableUtils::is_potential_table_row("1) Item with | pipe"));
        assert!(!TableUtils::is_potential_table_row("10) Item with | pipe"));

        // Unordered list items with tabs
        assert!(!TableUtils::is_potential_table_row("-\tItem with | pipe"));
        assert!(!TableUtils::is_potential_table_row("*\tItem with | pipe"));
        assert!(!TableUtils::is_potential_table_row("+\tItem with | pipe"));

        // Indented list items (the trim_start normalizes indentation)
        assert!(!TableUtils::is_potential_table_row("  - Indented | pipe"));
        assert!(!TableUtils::is_potential_table_row("    * Deep indent | pipe"));
        assert!(!TableUtils::is_potential_table_row("  1. Ordered indent | pipe"));

        // Task list items
        assert!(!TableUtils::is_potential_table_row("- [ ] task | pipe"));
        assert!(!TableUtils::is_potential_table_row("- [x] done | pipe"));

        // Multiple pipes in list items
        assert!(!TableUtils::is_potential_table_row("1. foo | bar | baz"));
        assert!(!TableUtils::is_potential_table_row("- alpha | beta | gamma"));

        // These SHOULD still be detected as potential table rows
        assert!(TableUtils::is_potential_table_row("| cell | cell |"));
        assert!(TableUtils::is_potential_table_row("cell | cell"));
        assert!(TableUtils::is_potential_table_row("| Header | Header |"));
    }

    #[test]
    fn test_atx_headings_with_pipes_not_table_rows() {
        // All 6 ATX heading levels with pipes
        assert!(!TableUtils::is_potential_table_row("# Heading | with pipe"));
        assert!(!TableUtils::is_potential_table_row("## Heading | with pipe"));
        assert!(!TableUtils::is_potential_table_row("### Heading | with pipe"));
        assert!(!TableUtils::is_potential_table_row("#### Heading | with pipe"));
        assert!(!TableUtils::is_potential_table_row("##### Heading | with pipe"));
        assert!(!TableUtils::is_potential_table_row("###### Heading | with pipe"));

        // Multiple pipes in headings
        assert!(!TableUtils::is_potential_table_row("### col1 | col2 | col3"));
        assert!(!TableUtils::is_potential_table_row("## a|b|c"));

        // Headings with tab after hashes
        assert!(!TableUtils::is_potential_table_row("#\tHeading | pipe"));
        assert!(!TableUtils::is_potential_table_row("##\tHeading | pipe"));

        // Heading with only hashes and pipe (empty heading text)
        assert!(!TableUtils::is_potential_table_row("# |"));
        assert!(!TableUtils::is_potential_table_row("## |"));

        // Indented headings (spaces before #)
        assert!(!TableUtils::is_potential_table_row("  ## Heading | pipe"));
        assert!(!TableUtils::is_potential_table_row("   ### Heading | pipe"));

        // Unicode content in headings (the original proptest failure case)
        assert!(!TableUtils::is_potential_table_row("#### ®aAA|ᯗ"));

        // 7+ hashes are NOT headings — should follow normal table detection
        // "####### text|pipe" has no space after 7 hashes if treated as non-heading
        // but with a space it still has 7+ hashes so not a heading
        assert!(TableUtils::is_potential_table_row("####### text | pipe"));

        // Hash without space is NOT a heading, so pipe detection applies
        assert!(TableUtils::is_potential_table_row("#nospc|pipe"));

        // These SHOULD still be detected as potential table rows
        assert!(TableUtils::is_potential_table_row("| # Header | Value |"));
        assert!(TableUtils::is_potential_table_row("text | #tag"));
    }

    #[test]
    fn test_is_delimiter_row() {
        // Basic delimiter rows
        assert!(TableUtils::is_delimiter_row("|---|---|"));
        assert!(TableUtils::is_delimiter_row("| --- | --- |"));
        assert!(TableUtils::is_delimiter_row("|:---|---:|"));
        assert!(TableUtils::is_delimiter_row("|:---:|:---:|"));

        // With varying dash counts
        assert!(TableUtils::is_delimiter_row("|-|--|"));
        assert!(TableUtils::is_delimiter_row("|-------|----------|"));

        // With whitespace
        assert!(TableUtils::is_delimiter_row("|  ---  |  ---  |"));
        assert!(TableUtils::is_delimiter_row("| :--- | ---: |"));

        // Multiple columns
        assert!(TableUtils::is_delimiter_row("|---|---|---|---|"));

        // Without leading/trailing pipes
        assert!(TableUtils::is_delimiter_row("--- | ---"));
        assert!(TableUtils::is_delimiter_row(":--- | ---:"));

        // Not delimiter rows
        assert!(!TableUtils::is_delimiter_row("| Header | Header |"));
        assert!(!TableUtils::is_delimiter_row("Regular text"));
        assert!(!TableUtils::is_delimiter_row(""));
        assert!(!TableUtils::is_delimiter_row("|||"));
        assert!(!TableUtils::is_delimiter_row("| | |"));

        // Must have dashes
        assert!(!TableUtils::is_delimiter_row("| : | : |"));
        assert!(!TableUtils::is_delimiter_row("|    |    |"));

        // Mixed content
        assert!(!TableUtils::is_delimiter_row("| --- | text |"));
        assert!(!TableUtils::is_delimiter_row("| abc | --- |"));
    }

    #[test]
    fn test_count_cells() {
        // Basic counts
        assert_eq!(TableUtils::count_cells("| Cell 1 | Cell 2 | Cell 3 |"), 3);
        assert_eq!(TableUtils::count_cells("Cell 1 | Cell 2 | Cell 3"), 3);
        assert_eq!(TableUtils::count_cells("| Cell 1 | Cell 2"), 2);
        assert_eq!(TableUtils::count_cells("Cell 1 | Cell 2 |"), 2);

        // Single cell
        assert_eq!(TableUtils::count_cells("| Cell |"), 1);
        assert_eq!(TableUtils::count_cells("Cell"), 0); // No pipe

        // Empty cells
        assert_eq!(TableUtils::count_cells("|  |  |  |"), 3);
        assert_eq!(TableUtils::count_cells("| | | |"), 3);

        // Many cells
        assert_eq!(TableUtils::count_cells("| A | B | C | D | E | F |"), 6);

        // Edge cases
        assert_eq!(TableUtils::count_cells("||"), 1); // One empty cell
        assert_eq!(TableUtils::count_cells("|||"), 2); // Two empty cells

        // No table
        assert_eq!(TableUtils::count_cells("Regular text"), 0);
        assert_eq!(TableUtils::count_cells(""), 0);
        assert_eq!(TableUtils::count_cells("   "), 0);

        // Whitespace handling
        assert_eq!(TableUtils::count_cells("  | A | B |  "), 2);
        assert_eq!(TableUtils::count_cells("|   A   |   B   |"), 2);
    }

    #[test]
    fn test_count_cells_with_escaped_pipes() {
        // Pipes inside code spans are treated as content, not cell delimiters.
        // To include a literal pipe outside code spans, escape it with \|.

        // Basic table structure
        assert_eq!(TableUtils::count_cells("| Challenge | Solution |"), 2);
        assert_eq!(TableUtils::count_cells("| A | B | C |"), 3);
        assert_eq!(TableUtils::count_cells("| One | Two |"), 2);

        // Escaped pipes: \| keeps the pipe as content
        assert_eq!(TableUtils::count_cells(r"| Command | echo \| grep |"), 2);
        assert_eq!(TableUtils::count_cells(r"| A | B \| C |"), 2); // B | C is one cell

        // Escaped pipes inside backticks
        assert_eq!(TableUtils::count_cells(r"| Command | `echo \| grep` |"), 2);

        // Double backslash + pipe: \\| means escaped backslash followed by pipe delimiter
        assert_eq!(TableUtils::count_cells(r"| A | B \\| C |"), 3); // \\| is NOT escaped pipe
        // Double backslash inside backticks: pipe is still masked by code span
        assert_eq!(TableUtils::count_cells(r"| A | `B \\| C` |"), 2);

        // Pipes inside code spans are content, not delimiters
        assert_eq!(TableUtils::count_cells("| Command | `echo | grep` |"), 2);
        assert_eq!(TableUtils::count_cells("| `code | one` | `code | two` |"), 2);
        assert_eq!(TableUtils::count_cells("| `single|pipe` |"), 1);

        // Regex example - pipes in code spans are masked
        assert_eq!(TableUtils::count_cells(r"| Hour formats | `^([0-1]?\d|2[0-3])` |"), 2);
        // Escaped pipe inside code is also masked (escape is redundant here)
        assert_eq!(TableUtils::count_cells(r"| Hour formats | `^([0-1]?\d\|2[0-3])` |"), 2);
    }

    #[test]
    fn test_determine_pipe_style() {
        // All pipe styles
        assert_eq!(
            TableUtils::determine_pipe_style("| Cell 1 | Cell 2 |"),
            Some("leading_and_trailing")
        );
        assert_eq!(
            TableUtils::determine_pipe_style("| Cell 1 | Cell 2"),
            Some("leading_only")
        );
        assert_eq!(
            TableUtils::determine_pipe_style("Cell 1 | Cell 2 |"),
            Some("trailing_only")
        );
        assert_eq!(
            TableUtils::determine_pipe_style("Cell 1 | Cell 2"),
            Some("no_leading_or_trailing")
        );

        // With whitespace
        assert_eq!(
            TableUtils::determine_pipe_style("  | Cell 1 | Cell 2 |  "),
            Some("leading_and_trailing")
        );
        assert_eq!(
            TableUtils::determine_pipe_style("  | Cell 1 | Cell 2  "),
            Some("leading_only")
        );

        // No pipes
        assert_eq!(TableUtils::determine_pipe_style("Regular text"), None);
        assert_eq!(TableUtils::determine_pipe_style(""), None);
        assert_eq!(TableUtils::determine_pipe_style("   "), None);

        // Single pipe cases
        assert_eq!(TableUtils::determine_pipe_style("|"), Some("leading_and_trailing"));
        assert_eq!(TableUtils::determine_pipe_style("| Cell"), Some("leading_only"));
        assert_eq!(TableUtils::determine_pipe_style("Cell |"), Some("trailing_only"));
    }

    #[test]
    fn test_determine_pipe_style_distinguishes_escaped_cell_pipes() {
        for backslashes in 0..=6 {
            let row = format!("A | B {}|", "\\".repeat(backslashes));
            let expected = if backslashes % 2 == 0 {
                "trailing_only"
            } else {
                "no_leading_or_trailing"
            };
            for prefix in ["", "> ", ">> "] {
                assert_eq!(
                    TableUtils::determine_pipe_style(&format!("{prefix}{row}")),
                    Some(expected)
                );
            }
        }
    }

    #[test]
    fn test_find_table_blocks_simple() {
        let content = "| Header 1 | Header 2 |
|-----------|-----------|
| Cell 1    | Cell 2    |
| Cell 3    | Cell 4    |";

        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);

        let tables = TableUtils::find_table_blocks(content, &ctx);
        assert_eq!(tables.len(), 1);

        let table = &tables[0];
        assert_eq!(table.start_line, 0);
        assert_eq!(table.end_line, 3);
        assert_eq!(table.header_line, 0);
        assert_eq!(table.delimiter_line, 1);
        assert_eq!(table.content_lines, vec![2, 3]);
    }

    #[test]
    fn test_find_table_blocks_multiple() {
        let content = "Some text

| Table 1 | Col A |
|----------|-------|
| Data 1   | Val 1 |

More text

| Table 2 | Col 2 |
|----------|-------|
| Data 2   | Data  |";

        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);

        let tables = TableUtils::find_table_blocks(content, &ctx);
        assert_eq!(tables.len(), 2);

        // First table
        assert_eq!(tables[0].start_line, 2);
        assert_eq!(tables[0].end_line, 4);
        assert_eq!(tables[0].header_line, 2);
        assert_eq!(tables[0].delimiter_line, 3);
        assert_eq!(tables[0].content_lines, vec![4]);

        // Second table
        assert_eq!(tables[1].start_line, 8);
        assert_eq!(tables[1].end_line, 10);
        assert_eq!(tables[1].header_line, 8);
        assert_eq!(tables[1].delimiter_line, 9);
        assert_eq!(tables[1].content_lines, vec![10]);
    }

    #[test]
    fn test_find_table_blocks_no_content_rows() {
        let content = "| Header 1 | Header 2 |
|-----------|-----------|

Next paragraph";

        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);

        let tables = TableUtils::find_table_blocks(content, &ctx);
        assert_eq!(tables.len(), 1);

        let table = &tables[0];
        assert_eq!(table.start_line, 0);
        assert_eq!(table.end_line, 1); // Just header and delimiter
        assert_eq!(table.content_lines.len(), 0);
    }

    #[test]
    fn test_find_table_blocks_in_code_block() {
        let content = "```
| Not | A | Table |
|-----|---|-------|
| In  | Code | Block |
```

| Real | Table |
|------|-------|
| Data | Here  |";

        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);

        let tables = TableUtils::find_table_blocks(content, &ctx);
        assert_eq!(tables.len(), 1); // Only the table outside code block

        let table = &tables[0];
        assert_eq!(table.header_line, 6);
        assert_eq!(table.delimiter_line, 7);
    }

    #[test]
    fn test_find_table_blocks_no_tables() {
        let content = "Just regular text
No tables here
- List item with | pipe
* Another list item";

        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);

        let tables = TableUtils::find_table_blocks(content, &ctx);
        assert_eq!(tables.len(), 0);
    }

    #[test]
    fn test_find_table_blocks_malformed() {
        let content = "| Header without delimiter |
| This looks like table |
But no delimiter row

| Proper | Table |
|---------|-------|
| Data    | Here  |";

        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);

        let tables = TableUtils::find_table_blocks(content, &ctx);
        assert_eq!(tables.len(), 1); // Only the proper table
        assert_eq!(tables[0].header_line, 4);
    }

    #[test]
    fn test_find_table_blocks_keeps_obsidian_wikilink_prose_out_of_the_table() {
        let content = "| A | B |\n| - | - |\n| x | y |\n[[Foo|bar]] is a note.\n";

        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Obsidian, None);
        let blocks = TableUtils::find_table_blocks(content, &ctx);
        assert_eq!(blocks.len(), 1, "Expected one table, got {blocks:?}");
        assert_eq!(
            blocks[0].end_line, 2,
            "Wikilink prose was absorbed into the table: {:?}",
            blocks[0]
        );
        assert_eq!(blocks[0].content_lines, vec![2]);

        // Control: under GFM the same pipe is a cell delimiter, so the line really
        // is a table row and belongs to the block.
        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);
        let blocks = TableUtils::find_table_blocks(content, &ctx);
        assert_eq!(blocks.len(), 1, "Expected one table, got {blocks:?}");
        assert_eq!(
            blocks[0].end_line, 3,
            "GFM should still read the pipe as a delimiter: {:?}",
            blocks[0]
        );
    }

    #[test]
    fn test_edge_cases() {
        // Test empty content
        assert!(!TableUtils::is_potential_table_row(""));
        assert!(!TableUtils::is_delimiter_row(""));
        assert_eq!(TableUtils::count_cells(""), 0);
        assert_eq!(TableUtils::determine_pipe_style(""), None);

        // Test whitespace only
        assert!(!TableUtils::is_potential_table_row("   "));
        assert!(!TableUtils::is_delimiter_row("   "));
        assert_eq!(TableUtils::count_cells("   "), 0);
        assert_eq!(TableUtils::determine_pipe_style("   "), None);

        // Test single character
        assert!(!TableUtils::is_potential_table_row("|"));
        assert!(!TableUtils::is_delimiter_row("|"));
        assert_eq!(TableUtils::count_cells("|"), 0); // Need at least 2 parts

        // Test very long lines are valid table rows (no length limit)
        // Test both single-column and multi-column long lines
        let long_single = format!("| {} |", "a".repeat(200));
        assert!(TableUtils::is_potential_table_row(&long_single)); // Single-column table with long content

        let long_multi = format!("| {} | {} |", "a".repeat(200), "b".repeat(200));
        assert!(TableUtils::is_potential_table_row(&long_multi)); // Multi-column table with long content

        // Test unicode
        assert!(TableUtils::is_potential_table_row("| 你好 | 世界 |"));
        assert!(TableUtils::is_potential_table_row("| émoji | 🎉 |"));
        assert_eq!(TableUtils::count_cells("| 你好 | 世界 |"), 2);
    }

    #[test]
    fn test_table_block_struct() {
        let block = TableBlock {
            start_line: 0,
            end_line: 5,
            header_line: 0,
            delimiter_line: 1,
            content_lines: vec![2, 3, 4, 5],
            list_context: None,
        };

        // Test Debug trait
        let debug_str = format!("{block:?}");
        assert!(debug_str.contains("TableBlock"));
        assert!(debug_str.contains("start_line: 0"));

        // Test Clone trait
        let cloned = block.clone();
        assert_eq!(cloned.start_line, block.start_line);
        assert_eq!(cloned.end_line, block.end_line);
        assert_eq!(cloned.header_line, block.header_line);
        assert_eq!(cloned.delimiter_line, block.delimiter_line);
        assert_eq!(cloned.content_lines, block.content_lines);
        assert!(cloned.list_context.is_none());
    }

    #[test]
    fn test_split_table_row() {
        // Basic split
        let cells = TableUtils::split_table_row("| Cell 1 | Cell 2 | Cell 3 |");
        assert_eq!(cells.len(), 3);
        assert_eq!(cells[0].trim(), "Cell 1");
        assert_eq!(cells[1].trim(), "Cell 2");
        assert_eq!(cells[2].trim(), "Cell 3");

        // Without trailing pipe
        let cells = TableUtils::split_table_row("| Cell 1 | Cell 2");
        assert_eq!(cells.len(), 2);

        // Empty cells
        let cells = TableUtils::split_table_row("| | | |");
        assert_eq!(cells.len(), 3);

        // Single cell
        let cells = TableUtils::split_table_row("| Cell |");
        assert_eq!(cells.len(), 1);
        assert_eq!(cells[0].trim(), "Cell");

        // No pipes
        let cells = TableUtils::split_table_row("No pipes here");
        assert_eq!(cells.len(), 0);
    }

    #[test]
    fn test_split_table_row_with_escaped_pipes() {
        // Escaped pipes should be preserved in cell content
        let cells = TableUtils::split_table_row(r"| A | B \| C |");
        assert_eq!(cells.len(), 2);
        assert!(cells[1].contains(r"\|"), "Escaped pipe should be in cell content");

        // Double backslash + pipe is NOT escaped
        let cells = TableUtils::split_table_row(r"| A | B \\| C |");
        assert_eq!(cells.len(), 3);
    }

    #[test]
    fn test_split_table_row_with_flavor_mkdocs() {
        // MkDocs flavor: pipes in inline code are NOT cell delimiters
        let cells =
            TableUtils::split_table_row_with_flavor("| Type | `x | y` |", crate::config::MarkdownFlavor::MkDocs);
        assert_eq!(cells.len(), 2);
        assert!(
            cells[1].contains("`x | y`"),
            "Inline code with pipe should be single cell in MkDocs flavor"
        );

        // Multiple pipes in inline code
        let cells =
            TableUtils::split_table_row_with_flavor("| Type | `a | b | c` |", crate::config::MarkdownFlavor::MkDocs);
        assert_eq!(cells.len(), 2);
        assert!(cells[1].contains("`a | b | c`"));
    }

    #[test]
    fn test_split_table_row_with_flavor_standard() {
        // Pipes in inline code are NOT cell delimiters for any flavor
        let cells =
            TableUtils::split_table_row_with_flavor("| Type | `x | y` |", crate::config::MarkdownFlavor::Standard);
        assert_eq!(
            cells.len(),
            2,
            "Pipes in code spans should not be cell delimiters, got {cells:?}"
        );
        assert!(
            cells[1].contains("`x | y`"),
            "Inline code with pipe should be single cell"
        );
    }

    #[test]
    fn test_split_table_row_with_flavor_obsidian_wikilink() {
        // Obsidian flavor: the pipe in [[Target|Label]] separates a link from its
        // alias, not one cell from the next
        let cells = TableUtils::split_table_row_with_flavor(
            "| Alice | [[White Rabbit|the Rabbit]] |",
            crate::config::MarkdownFlavor::Obsidian,
        );
        assert_eq!(cells.len(), 2, "Aliased wikilink should be one cell, got {cells:?}");
        assert!(cells[1].contains("[[White Rabbit|the Rabbit]]"));

        // Two aliased wikilinks in one cell
        let cells = TableUtils::split_table_row_with_flavor(
            "| Guests | [[Mad Hatter|the Hatter]] and [[March Hare|the Hare]] |",
            crate::config::MarkdownFlavor::Obsidian,
        );
        assert_eq!(
            cells.len(),
            2,
            "Two aliased wikilinks should be one cell, got {cells:?}"
        );

        // A plain wikilink has no pipe to mask
        let cells = TableUtils::split_table_row_with_flavor(
            "| Alice | [[Cheshire Cat]] |",
            crate::config::MarkdownFlavor::Obsidian,
        );
        assert_eq!(cells.len(), 2);

        // An unterminated wikilink must not swallow the rest of the row
        let cells = TableUtils::split_table_row_with_flavor(
            "| Alice | [[White Rabbit | curious |",
            crate::config::MarkdownFlavor::Obsidian,
        );
        assert_eq!(
            cells.len(),
            3,
            "Unterminated wikilink should not mask pipes, got {cells:?}"
        );
    }

    #[test]
    fn test_split_table_row_wikilink_only_for_obsidian() {
        // Other flavors keep GFM behaviour: an unescaped pipe is a cell delimiter
        for flavor in [
            crate::config::MarkdownFlavor::Standard,
            crate::config::MarkdownFlavor::MkDocs,
        ] {
            let cells = TableUtils::split_table_row_with_flavor("| Alice | [[White Rabbit|the Rabbit]] |", flavor);
            assert_eq!(
                cells.len(),
                3,
                "{flavor:?} should treat the wikilink pipe as a delimiter, got {cells:?}"
            );
        }
    }

    #[test]
    fn test_mask_pipes_in_wikilinks_preserves_length() {
        // Masking must not change length, or cell offsets drift
        for text in [
            "| Alice | [[White Rabbit|the Rabbit]] |",
            "| [[Mad Hatter|Hatter]] | [[March Hare|Hare]] |",
            "no wikilink here | just a pipe",
            "[[unterminated | still text",
        ] {
            assert_eq!(
                TableUtils::mask_pipes_in_wikilinks(text).len(),
                text.len(),
                "masking changed length of {text:?}"
            );
        }
    }

    #[test]
    fn test_wikilink_brackets_in_a_code_span_stay_prose() {
        // Code binds tighter than a link, so brackets quoted as code open nothing.
        // Reading them as a link would merge four well-formed cells into fewer and
        // report a column-count mismatch against a table that has none.
        for row in [
            "| `[[` | mid | `]]` |",
            "| `[[Target` | mid | `Label]]` |",
            "| a | `[[` | b | `]]` |",
            // A quoted "[[" is not an opener even when a real "]]" follows it
            // outside the span, so the pipe between them stays a delimiter.
            "| `[[` and Target|Label]] |",
        ] {
            let obsidian = TableUtils::split_table_row_with_flavor(row, crate::config::MarkdownFlavor::Obsidian);
            let standard = TableUtils::split_table_row_with_flavor(row, crate::config::MarkdownFlavor::Standard);
            assert_eq!(
                obsidian, standard,
                "Obsidian disagreed with GFM about {row:?}: {obsidian:?} vs {standard:?}"
            );
        }

        // A code span inside a genuine wikilink is content of the alias, so the
        // link still closes at its own "]]" and the row is one cell.
        let cells = TableUtils::split_table_row_with_flavor(
            "| [[Target|Label with `a|b` inside]] |",
            crate::config::MarkdownFlavor::Obsidian,
        );
        assert_eq!(
            cells.len(),
            1,
            "Wikilink holding a code span should be one cell, got {cells:?}"
        );

        // A "]]" that only exists inside a code span does not close the link, so
        // there is nothing to mask and the pipes stay delimiters.
        let cells = TableUtils::split_table_row_with_flavor(
            "| [[Target | alias `]]` | tail |",
            crate::config::MarkdownFlavor::Obsidian,
        );
        assert_eq!(
            cells.len(),
            3,
            "A closer hidden in code should not close the link, got {cells:?}"
        );
    }

    #[test]
    fn test_wikilink_with_a_blank_target_stays_prose() {
        // The half before the pipe names the note, so a blank one means these
        // brackets are prose that happens to straddle a cell divider.
        for row in [
            "| [[ | ]] |",
            "| [[|Label]] |",
            "| starts [[ | ends ]] here |",
            "| [[\t|\tx]] |",
        ] {
            let obsidian = TableUtils::split_table_row_with_flavor(row, crate::config::MarkdownFlavor::Obsidian);
            let standard = TableUtils::split_table_row_with_flavor(row, crate::config::MarkdownFlavor::Standard);
            assert_eq!(
                obsidian, standard,
                "Obsidian disagreed with GFM about {row:?}: {obsidian:?} vs {standard:?}"
            );
        }

        // Positive control: one non-whitespace character of target is a link.
        let cells = TableUtils::split_table_row_with_flavor("| [[x | y]] |", crate::config::MarkdownFlavor::Obsidian);
        assert_eq!(cells.len(), 1, "A named target should be one cell, got {cells:?}");
    }

    #[test]
    fn test_inline_code_spans_agree_with_pipe_masking() {
        // Both maskers read one definition of a code span, so an unmatched run of
        // backticks is literal text to both and scanning resumes just after it.
        let text = "``x | y and `c|d`";
        let chars: Vec<char> = text.chars().collect();
        let spans = TableUtils::inline_code_spans(&chars);
        assert_eq!(spans.len(), 1, "Only the matched pair is a code span, got {spans:?}");
        let (start, end) = spans[0];
        assert_eq!(
            chars[start..end].iter().collect::<String>(),
            "`c|d`",
            "The span should start at the run that closes, not the unmatched opener"
        );

        // The pipe outside every span survives; the one inside is masked.
        assert_eq!(TableUtils::mask_pipes_in_inline_code(text), "``x | y and `c_d`");
    }

    // === extract_blockquote_prefix tests ===

    #[test]
    fn test_extract_blockquote_prefix_no_blockquote() {
        // Regular table row without blockquote
        let (prefix, content) = TableUtils::extract_blockquote_prefix("| H1 | H2 |");
        assert_eq!(prefix, "");
        assert_eq!(content, "| H1 | H2 |");
    }

    #[test]
    fn test_extract_blockquote_prefix_single_level() {
        // Single blockquote level
        let (prefix, content) = TableUtils::extract_blockquote_prefix("> | H1 | H2 |");
        assert_eq!(prefix, "> ");
        assert_eq!(content, "| H1 | H2 |");
    }

    #[test]
    fn test_extract_blockquote_prefix_double_level() {
        // Double blockquote level
        let (prefix, content) = TableUtils::extract_blockquote_prefix(">> | H1 | H2 |");
        assert_eq!(prefix, ">> ");
        assert_eq!(content, "| H1 | H2 |");
    }

    #[test]
    fn test_extract_blockquote_prefix_triple_level() {
        // Triple blockquote level
        let (prefix, content) = TableUtils::extract_blockquote_prefix(">>> | H1 | H2 |");
        assert_eq!(prefix, ">>> ");
        assert_eq!(content, "| H1 | H2 |");
    }

    #[test]
    fn test_extract_blockquote_prefix_with_spaces() {
        // Blockquote with spaces between markers
        let (prefix, content) = TableUtils::extract_blockquote_prefix("> > | H1 | H2 |");
        assert_eq!(prefix, "> > ");
        assert_eq!(content, "| H1 | H2 |");
    }

    #[test]
    fn test_extract_blockquote_prefix_indented() {
        // Indented blockquote
        let (prefix, content) = TableUtils::extract_blockquote_prefix("  > | H1 | H2 |");
        assert_eq!(prefix, "  > ");
        assert_eq!(content, "| H1 | H2 |");
    }

    #[test]
    fn test_extract_blockquote_prefix_no_space_after() {
        // Blockquote without space after marker
        let (prefix, content) = TableUtils::extract_blockquote_prefix(">| H1 | H2 |");
        assert_eq!(prefix, ">");
        assert_eq!(content, "| H1 | H2 |");
    }

    #[test]
    fn test_determine_pipe_style_in_blockquote() {
        // determine_pipe_style should handle blockquotes correctly
        assert_eq!(
            TableUtils::determine_pipe_style("> | H1 | H2 |"),
            Some("leading_and_trailing")
        );
        assert_eq!(
            TableUtils::determine_pipe_style("> H1 | H2"),
            Some("no_leading_or_trailing")
        );
        assert_eq!(
            TableUtils::determine_pipe_style(">> | H1 | H2 |"),
            Some("leading_and_trailing")
        );
        assert_eq!(TableUtils::determine_pipe_style(">>> | H1 | H2"), Some("leading_only"));
    }

    #[test]
    fn test_list_table_delimiter_requires_indentation() {
        // Test case: list item contains pipe, but delimiter line is at column 1
        // This should NOT be detected as a list table since the delimiter has no indentation.
        // The result is a non-list table starting at line 0 (the list item becomes the header)
        // but list_context should be None.
        let content = "- List item with | pipe\n|---|---|\n| Cell 1 | Cell 2 |";
        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);
        let tables = TableUtils::find_table_blocks(content, &ctx);

        // The table will be detected starting at line 0, but crucially it should NOT have
        // list_context set, meaning it won't be treated as a list-table for column count purposes
        assert_eq!(tables.len(), 1, "Should find exactly one table");
        assert!(
            tables[0].list_context.is_none(),
            "Should NOT have list context since delimiter has no indentation"
        );
    }

    #[test]
    fn test_list_table_with_properly_indented_delimiter() {
        // Test case: list item with table header, delimiter properly indented
        // This SHOULD be detected as a list table
        let content = "- | Header 1 | Header 2 |\n  |----------|----------|\n  | Cell 1   | Cell 2   |";
        let ctx = LintContext::new(content, crate::config::MarkdownFlavor::Standard, None);
        let tables = TableUtils::find_table_blocks(content, &ctx);

        // Should find exactly one list-table starting at line 0
        assert_eq!(tables.len(), 1, "Should find exactly one table");
        assert_eq!(tables[0].start_line, 0, "Table should start at list item line");
        assert!(
            tables[0].list_context.is_some(),
            "Should be a list table since delimiter is properly indented"
        );
    }

    #[test]
    fn test_mask_pipes_in_inline_code_regular_backticks() {
        // Regular backtick code span: pipe should be masked
        let result = TableUtils::mask_pipes_in_inline_code("| `code | here` |");
        assert_eq!(result, "| `code _ here` |");
    }

    #[test]
    fn test_mask_pipes_in_inline_code_escaped_backtick_not_code_span() {
        // Escaped backtick (\`) is literal text, not a code span opener.
        // The pipe should NOT be masked.
        let result = TableUtils::mask_pipes_in_inline_code(r"| \`not code | still pipe\` |");
        assert_eq!(result, r"| \`not code | still pipe\` |");
    }

    #[test]
    fn test_mask_pipes_in_inline_code_escaped_backslash_then_backtick() {
        // Escaped backslash (\\) followed by backtick: the backtick IS a code span opener.
        // The pipe inside the code span SHOULD be masked.
        let result = TableUtils::mask_pipes_in_inline_code(r"| \\`real code | masked\\` |");
        // \\` = escaped backslash + real backtick (code span opener)
        // The pipe between the backticks should be masked
        assert_eq!(result, r"| \\`real code _ masked\\` |");
    }

    #[test]
    fn test_mask_pipes_in_inline_code_triple_backslash_before_backtick() {
        // Three backslashes before backtick: odd count means backtick is escaped
        let result = TableUtils::mask_pipes_in_inline_code(r"| \\\`not code | pipe\\\` |");
        assert_eq!(result, r"| \\\`not code | pipe\\\` |");
    }

    #[test]
    fn test_mask_pipes_in_inline_code_four_backslashes_before_backtick() {
        // Four backslashes before backtick: even count means backtick is a real delimiter
        let result = TableUtils::mask_pipes_in_inline_code(r"| \\\\`code | here\\\\` |");
        assert_eq!(result, r"| \\\\`code _ here\\\\` |");
    }

    #[test]
    fn test_mask_pipes_in_inline_code_no_backslash() {
        // No backslashes at all: standard behavior, pipe inside code span is masked
        let result = TableUtils::mask_pipes_in_inline_code("before `a | b` after");
        assert_eq!(result, "before `a _ b` after");
    }

    #[test]
    fn test_mask_pipes_in_inline_code_no_code_span() {
        // No backticks at all: nothing should be masked
        let result = TableUtils::mask_pipes_in_inline_code("| col1 | col2 |");
        assert_eq!(result, "| col1 | col2 |");
    }

    #[test]
    fn test_mask_pipes_in_inline_code_backslash_before_closing_backtick() {
        // Per CommonMark spec, backslash escapes do NOT work inside code spans.
        // Inside a code span, `\` is a literal character. So `foo\` is a valid
        // code span containing "foo\", and the closing backtick is NOT escaped.
        //
        // Input: | `foo\` | bar |
        // The code span is `foo\` (backtick opens, backslash is literal, backtick closes).
        // The pipe after the code span is a real delimiter, producing 2 cells.
        // The pipe inside the code span should be left alone (there isn't one here).
        let result = TableUtils::mask_pipes_in_inline_code(r"| `foo\` | bar |");
        // The backslash before closing backtick is literal inside the code span,
        // so the code span closes at that backtick. The pipe between cells is NOT masked.
        assert_eq!(result, r"| `foo\` | bar |");
    }

    #[test]
    fn test_mask_pipes_in_inline_code_backslash_literal_with_pipe_inside() {
        // Code span contains a backslash and a pipe: `a\|b`
        // The backslash is literal inside the code span (CommonMark spec).
        // The pipe is inside the code span, so it should be masked.
        let result = TableUtils::mask_pipes_in_inline_code(r"| `a\|b` | col2 |");
        assert_eq!(result, r"| `a\_b` | col2 |");
    }

    #[test]
    fn test_count_preceding_backslashes() {
        let chars: Vec<char> = r"abc\\\`def".chars().collect();
        // Position of backtick is at index 6 (a=0, b=1, c=2, \=3, \=4, \=5, `=6)
        assert_eq!(TableUtils::count_preceding_backslashes(&chars, 6), 3);

        let chars2: Vec<char> = r"abc\\`def".chars().collect();
        // Position of backtick is at index 5
        assert_eq!(TableUtils::count_preceding_backslashes(&chars2, 5), 2);

        let chars3: Vec<char> = "`def".chars().collect();
        // Position of backtick is at index 0 -- no preceding chars
        assert_eq!(TableUtils::count_preceding_backslashes(&chars3, 0), 0);
    }

    #[test]
    fn test_has_unescaped_pipe_backslash_literal_in_code_span() {
        // Per CommonMark: backslashes are literal inside code spans.
        // `foo\` is a complete code span, so the pipe after it is outside code.
        assert!(TableUtils::has_unescaped_pipe_outside_spans(r"`foo\` | bar"));

        // Escaped backtick outside code span: \` is not a code span opener
        assert!(TableUtils::has_unescaped_pipe_outside_spans(r"\`foo | bar\`"));

        // Pipe inside code span should not count
        assert!(!TableUtils::has_unescaped_pipe_outside_spans(r"`foo | bar`"));
    }

    #[test]
    fn test_table_after_code_span_detected() {
        use crate::config::MarkdownFlavor;

        let content = "`code`\n\n| A | B |\n|---|---|\n| 1 | 2 |\n";
        let ctx = LintContext::new(content, MarkdownFlavor::Standard, None);
        assert!(!ctx.table_blocks.is_empty(), "Table after code span should be detected");
    }

    #[test]
    fn test_table_inside_html_comment_not_detected() {
        use crate::config::MarkdownFlavor;

        let content = "<!--\n| A | B |\n|---|---|\n| 1 | 2 |\n-->\n";
        let ctx = LintContext::new(content, MarkdownFlavor::Standard, None);
        assert!(
            ctx.table_blocks.is_empty(),
            "Table inside HTML comment should not be detected"
        );
    }
}