From b1590a4fb0c28fdb6af866ea79c186ea57284493 Mon Sep 17 00:00:00 2001 From: Titus Wormer Date: Wed, 31 Aug 2022 16:50:20 +0200 Subject: Add support for GFM tables --- src/compiler.rs | 235 +++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 232 insertions(+), 3 deletions(-) (limited to 'src/compiler.rs') diff --git a/src/compiler.rs b/src/compiler.rs index 9057505..5626f8a 100644 --- a/src/compiler.rs +++ b/src/compiler.rs @@ -68,6 +68,43 @@ struct Definition { title: Option, } +/// GFM table: column alignment. +#[derive(Debug, PartialEq, Eq, Copy, Clone)] +enum GfmTableAlign { + /// No alignment. + /// + /// ```markdown + /// | | aaa | + /// > | | --- | + /// ^^^ + /// ``` + None, + /// Left alignment. + /// + /// ```markdown + /// | | aaa | + /// > | | :-- | + /// ^^^ + /// ``` + Left, + /// Center alignment. + /// + /// ```markdown + /// | | aaa | + /// > | | :-: | + /// ^^^ + /// ``` + Center, + /// Right alignment. + /// + /// ```markdown + /// | | aaa | + /// > | | --: | + /// ^^^ + /// ``` + Right, +} + /// Context used to compile markdown. #[allow(clippy::struct_excessive_bools)] #[derive(Debug)] @@ -107,6 +144,12 @@ struct CompileContext<'a> { pub gfm_footnote_definitions: Vec<(String, String)>, pub gfm_footnote_definition_calls: Vec<(String, usize)>, pub gfm_footnote_definition_stack: Vec<(usize, usize)>, + /// Whether we are in a GFM table head. + pub gfm_table_in_head: bool, + /// Current GFM table alignment. + pub gfm_table_align: Option>, + /// Current GFM table column. + pub gfm_table_column: usize, // Fields used to influance the current compilation. /// Ignore the next line ending. pub slurp_one_line_ending: bool, @@ -153,6 +196,9 @@ impl<'a> CompileContext<'a> { gfm_footnote_definitions: vec![], gfm_footnote_definition_calls: vec![], gfm_footnote_definition_stack: vec![], + gfm_table_in_head: false, + gfm_table_align: None, + gfm_table_column: 0, tight_stack: vec![], slurp_one_line_ending: false, image_alt_inside: false, @@ -350,6 +396,11 @@ fn enter(context: &mut CompileContext) { Name::GfmFootnoteDefinition => on_enter_gfm_footnote_definition(context), Name::GfmFootnoteCall => on_enter_gfm_footnote_call(context), Name::GfmStrikethrough => on_enter_gfm_strikethrough(context), + Name::GfmTable => on_enter_gfm_table(context), + Name::GfmTableBody => on_enter_gfm_table_body(context), + Name::GfmTableCell => on_enter_gfm_table_cell(context), + Name::GfmTableHead => on_enter_gfm_table_head(context), + Name::GfmTableRow => on_enter_gfm_table_row(context), Name::GfmTaskListItemCheck => on_enter_gfm_task_list_item_check(context), Name::HtmlFlow => on_enter_html_flow(context), Name::HtmlText => on_enter_html_text(context), @@ -407,6 +458,11 @@ fn exit(context: &mut CompileContext) { Name::GfmFootnoteDefinitionPrefix => on_exit_gfm_footnote_definition_prefix(context), Name::GfmFootnoteDefinition => on_exit_gfm_footnote_definition(context), Name::GfmStrikethrough => on_exit_gfm_strikethrough(context), + Name::GfmTable => on_exit_gfm_table(context), + Name::GfmTableBody => on_exit_gfm_table_body(context), + Name::GfmTableCell => on_exit_gfm_table_cell(context), + Name::GfmTableHead => on_exit_gfm_table_head(context), + Name::GfmTableRow => on_exit_gfm_table_row(context), Name::GfmTaskListItemCheck => on_exit_gfm_task_list_item_check(context), Name::GfmTaskListItemValueChecked => on_exit_gfm_task_list_item_value_checked(context), Name::HardBreakEscape | Name::HardBreakTrailing => on_exit_break(context), @@ -536,6 +592,105 @@ fn on_enter_gfm_strikethrough(context: &mut CompileContext) { } } +/// Handle [`Enter`][Kind::Enter]:[`GfmTable`][Name::GfmTable]. +fn on_enter_gfm_table(context: &mut CompileContext) { + // Find the alignment. + let mut index = context.index; + let mut in_delimiter_row = false; + let mut align = vec![]; + + while index < context.events.len() { + let event = &context.events[index]; + + if in_delimiter_row { + if event.kind == Kind::Enter { + // Start of alignment value: set a new column. + if event.name == Name::GfmTableDelimiterCellValue { + align.push( + if context.events[index + 1].name == Name::GfmTableDelimiterMarker { + GfmTableAlign::Left + } else { + GfmTableAlign::None + }, + ); + } + } else { + // End of alignment value: change the column. + if event.name == Name::GfmTableDelimiterCellValue { + if context.events[index - 1].name == Name::GfmTableDelimiterMarker { + let align_index = align.len() - 1; + align[align_index] = if align[align_index] == GfmTableAlign::Left { + GfmTableAlign::Center + } else { + GfmTableAlign::Right + } + } + } + // Done! + else if event.name == Name::GfmTableDelimiterRow { + break; + } + } + } else if event.kind == Kind::Enter && event.name == Name::GfmTableDelimiterRow { + in_delimiter_row = true; + } + + index += 1; + } + + // Generate. + context.gfm_table_align = Some(align); + context.line_ending_if_needed(); + context.push(""); +} + +/// Handle [`Enter`][Kind::Enter]:[`GfmTableBody`][Name::GfmTableBody]. +fn on_enter_gfm_table_body(context: &mut CompileContext) { + context.push(""); +} + +/// Handle [`Enter`][Kind::Enter]:[`GfmTableCell`][Name::GfmTableCell]. +fn on_enter_gfm_table_cell(context: &mut CompileContext) { + let column = context.gfm_table_column; + let align = context.gfm_table_align.as_ref().unwrap(); + + if column >= align.len() { + // Capture cell to ignore it. + context.buffer(); + } else { + let value = align[column]; + context.line_ending_if_needed(); + + if context.gfm_table_in_head { + context.push(" context.push(" align=\"left\""), + GfmTableAlign::Right => context.push(" align=\"right\""), + GfmTableAlign::Center => context.push(" align=\"center\""), + GfmTableAlign::None => {} + } + + context.push(">"); + } +} + +/// Handle [`Enter`][Kind::Enter]:[`GfmTableHead`][Name::GfmTableHead]. +fn on_enter_gfm_table_head(context: &mut CompileContext) { + context.line_ending_if_needed(); + context.push(""); + context.gfm_table_in_head = true; +} + +/// Handle [`Enter`][Kind::Enter]:[`GfmTableRow`][Name::GfmTableRow]. +fn on_enter_gfm_table_row(context: &mut CompileContext) { + context.line_ending_if_needed(); + context.push(""); +} + /// Handle [`Enter`][Kind::Enter]:[`GfmTaskListItemCheck`][Name::GfmTaskListItemCheck]. fn on_enter_gfm_task_list_item_check(context: &mut CompileContext) { if !context.image_alt_inside { @@ -892,7 +1047,24 @@ fn on_exit_raw_flow(context: &mut CompileContext) { /// Handle [`Exit`][Kind::Exit]:{[`CodeText`][Name::CodeText],[`MathText`][Name::MathText]}. fn on_exit_raw_text(context: &mut CompileContext) { let result = context.resume(); - let mut bytes = result.as_bytes(); + let mut bytes = result.as_bytes().to_vec(); + + // If we are in a GFM table, we need to decode escaped pipes. + // This is a rather weird GFM feature. + if context.gfm_table_align.is_some() { + let mut index = 0; + let mut len = bytes.len(); + + while index < len { + if index + 1 < len && bytes[index] == b'\\' && bytes[index + 1] == b'|' { + bytes.remove(index); + len -= 1; + } + + index += 1; + } + } + let mut trim = false; let mut index = 0; let mut end = bytes.len(); @@ -910,11 +1082,12 @@ fn on_exit_raw_text(context: &mut CompileContext) { } if trim { - bytes = &bytes[1..end]; + bytes.remove(0); + bytes.pop(); } context.raw_text_inside = false; - context.push(str::from_utf8(bytes).unwrap()); + context.push(str::from_utf8(&bytes).unwrap()); if !context.image_alt_inside { context.push(""); @@ -1113,6 +1286,62 @@ fn on_exit_gfm_strikethrough(context: &mut CompileContext) { } } +/// Handle [`Exit`][Kind::Exit]:[`GfmTable`][Name::GfmTable]. +fn on_exit_gfm_table(context: &mut CompileContext) { + context.gfm_table_align = None; + context.line_ending_if_needed(); + context.push("
"); +} + +/// Handle [`Exit`][Kind::Exit]:[`GfmTableBody`][Name::GfmTableBody]. +fn on_exit_gfm_table_body(context: &mut CompileContext) { + context.line_ending_if_needed(); + context.push(""); +} + +/// Handle [`Exit`][Kind::Exit]:[`GfmTableCell`][Name::GfmTableCell]. +fn on_exit_gfm_table_cell(context: &mut CompileContext) { + let align = context.gfm_table_align.as_ref().unwrap(); + + if context.gfm_table_column < align.len() { + if context.gfm_table_in_head { + context.push(""); + } else { + context.push(""); + } + } else { + // Stop capturing. + context.resume(); + } + + context.gfm_table_column += 1; +} + +/// Handle [`Exit`][Kind::Exit]:[`GfmTableHead`][Name::GfmTableHead]. +fn on_exit_gfm_table_head(context: &mut CompileContext) { + context.gfm_table_in_head = false; + context.line_ending_if_needed(); + context.push(""); +} + +/// Handle [`Exit`][Kind::Exit]:[`GfmTableRow`][Name::GfmTableRow]. +fn on_exit_gfm_table_row(context: &mut CompileContext) { + let mut column = context.gfm_table_column; + let len = context.gfm_table_align.as_ref().unwrap().len(); + + // Add “phantom” cells, for body rows that are shorter than the delimiter + // row (which is equal to the head row). + while column < len { + on_enter_gfm_table_cell(context); + on_exit_gfm_table_cell(context); + column += 1; + } + + context.gfm_table_column = 0; + context.line_ending_if_needed(); + context.push(""); +} + /// Handle [`Exit`][Kind::Exit]:[`GfmTaskListItemCheck`][Name::GfmTaskListItemCheck]. fn on_exit_gfm_task_list_item_check(context: &mut CompileContext) { if !context.image_alt_inside { -- cgit