parser

src/objects/emphasis.rs

@@ -0,0 +1,49 @@
+pub struct Emphasis;
+
+impl Emphasis {
+    pub fn parse(src: &str, marker: u8) -> Option<(&'_ str, usize)> {
+        expect!(src, 1, |c: u8| !c.is_ascii_whitespace());
+
+        let mut lines = 0;
+        let end = until_while!(src, 1, marker, |c| {
+            if c == b'\n' {
+                lines += 1;
+            }
+            lines < 2
+        });
+
+        expect!(src, end - 1, |c: u8| !c.is_ascii_whitespace());
+
+        if end < src.len() - 1 {
+            expect!(src, end + 1, |ch| ch == b' '
+                || ch == b'-'
+                || ch == b'.'
+                || ch == b','
+                || ch == b':'
+                || ch == b'!'
+                || ch == b'?'
+                || ch == b'\''
+                || ch == b')'
+                || ch == b'}');
+        }
+
+        Some((&src[1..end], end + 1))
+    }
+}
+
+#[test]
+fn parse() {
+    assert_eq!(
+        Emphasis::parse("*bold*", b'*').unwrap(),
+        ("bold", "*bold*".len())
+    );
+    assert_eq!(
+        Emphasis::parse("*bo\nld*", b'*').unwrap(),
+        ("bo\nld", "*bo\nld*".len())
+    );
+    assert!(Emphasis::parse("*bold*a", b'*').is_none());
+    assert!(Emphasis::parse("*bold*", b'/').is_none());
+    assert!(Emphasis::parse("*bold *", b'*').is_none());
+    assert!(Emphasis::parse("* bold*", b'*').is_none());
+    assert!(Emphasis::parse("*b\nol\nd*", b'*').is_none());
+}