treat newline as space at start and end of inline code

src/cm.rs

@@ -548,11 +548,14 @@ impl<'a, 'o> CommonMarkFormatter<'a, 'o> {
             for _ in 0..numticks {
                 write!(self, "`").unwrap();
             }
+
+            let all_space = literal.iter().all(|&c| c==b' ' || c==b'\r' || c==b'\n');
+            let has_edge_space = literal[0] == b' ' || literal[literal.len() - 1] == b' ';
+            let has_edge_backtick =  literal[0] == b'`' || literal[literal.len() - 1] == b'`';
+
             let pad = literal.is_empty()
-                || literal[0] == b'`'
-                || literal[literal.len() - 1] == b'`'
-                || literal[0] == b' '
-                || literal[literal.len() - 1] == b' ';
+                || has_edge_backtick
+                || (!all_space && has_edge_space);
             if pad {
                 write!(self, " ").unwrap();
             }

src/strings.rs

@@ -65,7 +65,7 @@ pub fn normalize_code(v: &[u8]) -> Vec<u8> {
             }
             c => r.push(c),
         }
-        if v[i] != b' ' {
+        if v[i] != b' ' && v[i] != b'\r' && v[i] != b'\n' {
             contains_nonspace = true;
         }
 
@@ -274,3 +274,18 @@ pub fn extract_attributes_from_tag(html_tag: &str) -> HashMap<String, String> {
 
     attributes
 }
+
+#[cfg(test)]
+pub mod tests {
+    use super::normalize_code;
+
+    #[test]
+    pub fn normalize_code_handles_lone_newline() {
+        assert_eq!(normalize_code(&[b'\n']), vec![b' ']);
+    }
+
+    #[test]
+    pub fn normalize_code_handles_lone_space() {
+        assert_eq!(normalize_code(&[b' ']), vec![b' ']);
+    }
+}

src/tests.rs

@@ -403,6 +403,11 @@ fn backticks() {
     );
 }
 
+#[test]
+fn backticks_empty_with_newline_should_be_space() {
+    html("`\n`", "<p><code> </code></p>\n");
+}
+
 #[test]
 fn backticks_num() {
     let input = "Some `code1`. More ``` code2 ```.\n";