Start of multiline comment highlighting

src/editor.rs

@@ -38,6 +38,8 @@ pub struct EditorSyntax {
     keywords1: Vec<&'static str>,
     keywords2: Vec<&'static str>,
     singleline_comment_start: String,
+    multiline_comment_start: String,
+    multiline_comment_end: String,
     flags: EditorSyntaxFlags,
 }
 
@@ -48,14 +50,18 @@ impl EditorSyntax {
         keywords1: Vec<&'static str>,
         keywords2: Vec<&'static str>,
         single_line_comment_start: &str,
+        multi_line_comment_start: &str,
+        multi_line_comment_end: &str,
         flags: EditorSyntaxFlags,
     ) -> Self {
         EditorSyntax {
-            file_type: String::from(file_type),
+            file_type: file_type.to_owned(),
             file_match,
             keywords1,
             keywords2,
-            singleline_comment_start: String::from(single_line_comment_start),
+            singleline_comment_start: single_line_comment_start.to_owned(),
+            multiline_comment_start: multi_line_comment_start.to_owned(),
+            multiline_comment_end: multi_line_comment_end.to_owned(),
             flags,
         }
     }
@@ -65,6 +71,7 @@ impl EditorSyntax {
 pub enum Highlight {
     Normal,
     LineComment,
+    MultiLineComment,
     Keyword1,
     Keyword2,
     String,
@@ -380,15 +387,18 @@ impl Editor {
         let keywords1 = &current_syntax.keywords1;
         let keywords2 = &current_syntax.keywords2;
 
-        let scs = current_syntax.singleline_comment_start.clone();
+        let scs = &current_syntax.singleline_comment_start;
+        let mcs = &current_syntax.multiline_comment_start;
+        let mce = &current_syntax.multiline_comment_end;
 
         let mut prev_separator = false;
         let mut in_string = false;
         let mut str_start = '\0';
+        let mut in_comment = false;
 
         let mut i = 0;
         let bytes = row.render.clone().into_bytes();
-        while i < row.render.len() {
+        'outer: while i < row.render.len() {
             let c = bytes[i] as char;
             let prev_highlight = if i > 0 {
                 row.highlight[i - 1]
@@ -398,7 +408,7 @@ impl Editor {
 
             // Single line comments
             if scs.len() > 0 && !in_string {
-                let comment = row.render.find(&scs);
+                let comment = row.render.find(scs);
                 if comment.is_some() {
                     // Pretty simple, highlight from the match to the end of the line
                     let comment_start = comment.unwrap();
@@ -408,6 +418,47 @@ impl Editor {
                 }
             }
 
+            // Multi-line comments
+            if mcs.len() > 0 && mce.len() > 0 && !in_string {
+                let mce_slice_range = if i as usize + mce.len() >= row.render.len() {
+                    i as usize..row.render.len()
+                } else {
+                    i as usize..(i as usize + mce.len())
+                };
+                let mcs_slice_range = if i as usize + mcs.len() >= row.render.len() {
+                    i as usize..row.render.len()
+                } else {
+                    i as usize..(i as usize + mcs.len())
+                };
+                if in_comment {
+                    row.highlight[i as usize] = Highlight::MultiLineComment;
+
+                    // End of a comment
+                    if &row.render[mce_slice_range.clone()] == mce {
+                        for x in mce_slice_range {
+                            row.highlight[x] = Highlight::MultiLineComment;
+                        }
+
+                        i += mce.len();
+                        in_comment = false;
+                        prev_separator = true;
+                        continue;
+                    } else {
+                        i += 1;
+                        continue;
+                    }
+                } else if &row.render[mcs_slice_range.clone()] == mcs {
+                    // Start of a multi-line comment
+                    for x in mcs_slice_range {
+                        row.highlight[x] = Highlight::MultiLineComment;
+                    }
+
+                    i += mcs.len();
+                    in_comment = true;
+                    continue;
+                }
+            }
+
             // Strings
             if current_syntax
                 .flags
@@ -431,7 +482,7 @@ impl Editor {
                     prev_separator = true;
                     continue;
                 } else {
-                    if c == '"' || c == '\'' {
+                    if (c == '"' || c == '\'') && prev_separator {
                         in_string = true;
                         str_start = c;
                         row.highlight[i as usize] = Highlight::String;
@@ -461,9 +512,22 @@ impl Editor {
                 for &keyword in keywords1 {
                     let matches = row.render.match_indices(keyword);
                     for (start, _) in matches {
-                        let end = start + keyword.len();
+                        let next_char_offset = start + keyword.len() + 1;
-                        for x in start..end {
+                        let is_end_of_line = next_char_offset >= row.render.len();
-                            row.highlight[x] = Highlight::Keyword1;
+                        let next_char = if is_end_of_line {
+                            '\0'
+                        } else {
+                            bytes[next_char_offset] as char
+                        };
+
+                        if is_separator(next_char) {
+                            let end = start + keyword.len();
+                            for x in start..end {
+                                row.highlight[x] = Highlight::Keyword1;
+                            }
+                            i += keyword.len();
+                            prev_separator = false;
+                            continue 'outer;
                         }
                     }
                 }
@@ -471,9 +535,22 @@ impl Editor {
                 for &keyword in keywords2 {
                     let matches = row.render.match_indices(keyword);
                     for (start, _) in matches {
-                        let end = start + keyword.len();
+                        let next_char_offset = start + keyword.len() + 1;
-                        for x in start..end {
+                        let is_end_of_line = next_char_offset >= row.render.len();
-                            row.highlight[x] = Highlight::Keyword2;
+                        let next_char = if is_end_of_line {
+                            '\0'
+                        } else {
+                            bytes[next_char_offset] as char
+                        };
+
+                        if is_separator(next_char) {
+                            let end = start + keyword.len();
+                            for x in start..end {
+                                row.highlight[x] = Highlight::Keyword2;
+                            }
+                            i += keyword.len();
+                            prev_separator = false;
+                            continue 'outer;
                         }
                     }
                 }
@@ -491,6 +568,7 @@ impl Editor {
             Keyword1 => 33,    // Yellow
             Keyword2 => 32,    // Green
             LineComment => 36, // Cyan
+            MultiLineComment => 36,
             Normal => 37,
             Number => 31,      // Red
             SearchMatch => 34, // Blue
@@ -815,7 +893,23 @@ impl Editor {
                 let mut current_color: i32 = -1;
 
                 for (x, ch) in output.char_indices() {
-                    if self.rows[file_row].highlight[x] == Highlight::Normal {
+                    if ch.is_ascii_control() {
+                        // Display unprintable characters in inverted colors
+                        let sym = if ch as u8 <= 26 {
+                            ('@' as u8 + ch as u8) as char
+                        } else {
+                            '?'
+                        };
+
+                        self.append_out("\x1b[7m");
+                        self.append_out_char(sym);
+                        self.append_out("\x1b[m");
+                        if current_color != -1 {
+                            let code = format!("\x1b[{}m", current_color);
+                            self.append_out(&code);
+                        }
+
+                    } else if self.rows[file_row].highlight[x] == Highlight::Normal {
                         if current_color != -1 {
                             self.append_out("\x1b[39m");
                             current_color = -1;
@@ -1276,6 +1370,8 @@ fn get_syntax_db() -> Vec<EditorSyntax> {
             ],
             vec!["int", "long", "double", "float", "char", "unsigned", "signed", "void"],
             "//",
+            "/*",
+            "*/",
             EditorSyntaxFlags::HIGHLIGHT_NUMBERS | EditorSyntaxFlags::HIGHLIGHT_STRINGS,
         ),
         EditorSyntax::new(
@@ -1345,21 +1441,27 @@ fn get_syntax_db() -> Vec<EditorSyntax> {
                 "f64"
             ],
             "//",
+            "/*",
+            "*/",
             EditorSyntaxFlags::HIGHLIGHT_NUMBERS | EditorSyntaxFlags::HIGHLIGHT_STRINGS,
         ),
     ]
 }
 
-fn is_separator(c: char) -> bool {
+fn is_separator(input_char: char) -> bool {
+    if  input_char.is_ascii_whitespace() || input_char == '\0' {
+        return true;
+    }
+
     let separator_chars = ",.()+-/*=~%<>[];";
 
     for ch in separator_chars.chars() {
-        if c == ch {
+        if input_char == ch {
             return true;
         }
     }
 
-    c.is_ascii_whitespace() || c == '\0'
+    false
 }
 
 #[cfg(test)]
@@ -1377,4 +1479,9 @@ mod tests {
         assert_eq!(editor.syntax.as_ref(), Some(&langs[0]));
     }
 
+    #[test]
+    fn is_separator_works() {
+        assert_eq!(is_separator(' '), true);
+        assert_eq!(is_separator('_'), false);
+    }
 }