Change whitespace behaviour

A single linebreak will be ignored in plain text while a double line
break will be converted to a single linebreak. All following
linebreaks are taken as-is and rendered as normal linebreaks.
(Fixes #13)

Signed-off-by: trivernis <trivernis@protonmail.com>

Cargo.lock

@@ -235,9 +235,9 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "charred"
-version = "0.3.5"
+version = "0.3.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed9759715d56a062d5636cd0cbc71f2aa8a978afe08c572a69e65e8cf53418f5"
+checksum = "4163b788273102d5de1aaf35a76b1c0e347844842f5278d4d738ad08170e0ea8"
 
 [[package]]
 name = "chrono"
@@ -2315,7 +2315,7 @@ checksum = "fe0f37c9e8f3c5a4a66ad655a93c74daac4ad00c441533bf5c6e7990bb42604e"
 
 [[package]]
 name = "snekdown"
-version = "0.32.3"
+version = "0.33.0"
 dependencies = [
  "asciimath-rs",
  "base64 0.12.3",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "snekdown"
-version = "0.32.3"
+version = "0.33.0"
 authors = ["trivernis <trivernis@protonmail.com>"]
 edition = "2018"
 license-file = "LICENSE"
@@ -21,7 +21,7 @@ path = "src/main.rs"
 pdf = ["headless_chrome", "failure"]
 
 [dependencies]
-charred = "0.3.5"
+charred = "0.3.6"
 asciimath-rs = "0.5.7"
 bibliographix = "0.6.0"
 crossbeam-utils = "0.7.2"

src/format/html/to_html.rs

@@ -251,7 +251,7 @@ impl ToHtml for Paragraph {
         }
         if self.elements.len() > 1 {
             for element in &self.elements[1..] {
-                writer.write("<br/>".to_string())?;
+                writer.write(" ".to_string())?;
                 element.to_html(writer)?;
             }
         }

src/parser/block.rs

@@ -165,6 +165,7 @@ impl ParseBlock for Parser {
     fn parse_quote(&mut self) -> ParseResult<Quote> {
         let start_index = self.ctm.get_index();
         self.ctm.seek_whitespace();
+
         let metadata = if let Ok(meta) = self.parse_inline_metadata() {
             Some(meta)
         } else {
@@ -199,11 +200,12 @@ impl ParseBlock for Parser {
 
     /// Parses a paragraph
     fn parse_paragraph(&mut self) -> ParseResult<Paragraph> {
-        self.ctm.seek_whitespace();
         let mut paragraph = Paragraph::new();
-        while let Ok(token) = self.parse_line() {
-            paragraph.add_element(token);
+
+        while let Ok(element) = self.parse_line() {
+            paragraph.add_element(element);
             let start_index = self.ctm.get_index();
+
             if self.ctm.check_any_sequence(&BLOCK_SPECIAL_CHARS)
                 || self.ctm.check_any(&self.block_break_at)
             {

src/parser/line.rs

@@ -1,7 +1,8 @@
 use super::ParseResult;
 use crate::elements::tokens::*;
+use crate::elements::Inline::LineBreak;
 use crate::elements::{BibEntry, Metadata};
-use crate::elements::{Cell, Centered, Header, Inline, Line, ListItem, Row, Ruler, TextLine};
+use crate::elements::{Cell, Centered, Header, Line, ListItem, Row, Ruler, TextLine};
 use crate::parser::inline::ParseInline;
 use crate::Parser;
 use bibliographix::bibliography::bibliography_entry::BibliographyEntry;
@@ -16,6 +17,7 @@ pub(crate) trait ParseLine {
     fn parse_row(&mut self) -> ParseResult<Row>;
     fn parse_centered(&mut self) -> ParseResult<Centered>;
     fn parse_ruler(&mut self) -> ParseResult<Ruler>;
+    fn parse_paragraph_break(&mut self) -> ParseResult<TextLine>;
     fn parse_text_line(&mut self) -> ParseResult<TextLine>;
     fn parse_bib_entry(&mut self) -> ParseResult<BibEntry>;
 }
@@ -36,6 +38,9 @@ impl ParseLine for Parser {
             } else if let Ok(bib) = self.parse_bib_entry() {
                 log::trace!("Line::BibEntry");
                 Ok(Line::BibEntry(bib))
+            } else if let Ok(text) = self.parse_paragraph_break() {
+                log::trace!("Line::LineBreak");
+                Ok(Line::Text(text))
             } else if let Ok(text) = self.parse_text_line() {
                 log::trace!("Line::Text");
                 Ok(Line::Text(text))
@@ -166,6 +171,8 @@ impl ParseLine for Parser {
     /// Parses a line of text
     fn parse_text_line(&mut self) -> ParseResult<TextLine> {
         let mut text = TextLine::new();
+        let start_index = self.ctm.get_index();
+
         while let Ok(subtext) = self.parse_inline() {
             text.add_subtext(subtext);
             if self.ctm.check_eof() || self.ctm.check_any(&self.inline_break_at) {
@@ -173,21 +180,36 @@ impl ParseLine for Parser {
             }
         }
 
+        // add a linebreak when encountering \n\n
         if self.ctm.check_char(&LB) {
-            if let Ok(_) = self.ctm.seek_one() {
+            self.ctm.try_seek();
+
             if self.ctm.check_char(&LB) {
-                    text.add_subtext(Inline::LineBreak)
-                }
+                text.add_subtext(LineBreak);
+
+                self.ctm.try_seek();
             }
         }
 
         if text.subtext.len() > 0 {
             Ok(text)
         } else {
-            Err(self.ctm.err().into())
+            Err(self.ctm.rewind_with_error(start_index).into())
         }
     }
 
+    /// Parses a paragraph break
+    fn parse_paragraph_break(&mut self) -> ParseResult<TextLine> {
+        let start_index = self.ctm.get_index();
+        self.ctm.assert_char(&LB, Some(start_index))?;
+        self.ctm.seek_one()?;
+
+        let mut line = TextLine::new();
+        line.subtext.push(LineBreak);
+
+        Ok(line)
+    }
+
     fn parse_bib_entry(&mut self) -> ParseResult<BibEntry> {
         let start_index = self.ctm.get_index();
         self.ctm.seek_any(&INLINE_WHITESPACE)?;
@@ -239,6 +261,7 @@ impl ParseLine for Parser {
                 }
             }
         };
+        self.ctm.seek_whitespace();
 
         self.options
             .document

src/parser/mod.rs

@@ -136,6 +136,11 @@ impl Parser {
     /// Returns a string of the current position in the file
     pub(crate) fn get_position_string(&self) -> String {
         let char_index = self.ctm.get_index();
+        self.get_position_string_for_index(char_index)
+    }
+
+    /// Returns a string of the given index position in the file
+    fn get_position_string_for_index(&self, char_index: usize) -> String {
         let text = self.ctm.get_text();
         let mut text_unil = text[..char_index].to_vec();
         let line_number = text_unil.iter().filter(|c| c == &&LB).count();
@@ -180,10 +185,10 @@ impl Parser {
         let anchor = Arc::new(RwLock::new(ImportAnchor::new()));
         let anchor_clone = Arc::clone(&anchor);
         let wg = self.wg.clone();
-        let mut chid_parser = self.create_child(path.clone());
+        let mut child_parser = self.create_child(path.clone());
 
         let _ = thread::spawn(move || {
-            let document = chid_parser.parse();
+            let document = child_parser.parse();
             anchor_clone.write().unwrap().set_document(document);
 
             drop(wg);
@@ -332,7 +337,18 @@ impl Parser {
                     if self.ctm.check_eof() {
                         break;
                     }
-                    eprintln!("{}", err);
+                    match err {
+                        ParseError::TapeError(t) => {
+                            log::error!(
+                                "Parse Error: {}\n\t--> {}\n",
+                                t,
+                                self.get_position_string_for_index(t.get_index())
+                            )
+                        }
+                        _ => {
+                            log::error!("{}", err)
+                        }
+                    }
                     break;
                 }
             }