parser

src/objects/link.rs

@@ -0,0 +1,68 @@
+#[cfg_attr(test, derive(PartialEq, Debug))]
+pub struct Link<'a> {
+    pub path: &'a str,
+    pub desc: Option<&'a str>,
+}
+
+impl<'a> Link<'a> {
+    pub fn parse(src: &'a str) -> Option<(Link<'a>, usize)> {
+        starts_with!(src, "[[");
+
+        let path = until_while!(src, 2, b']', |c| c != b']'
+            && c != b'<'
+            && c != b'>'
+            && c != b'\n');
+
+        if cond_eq!(src, path + 1, b']') {
+            Some((
+                Link {
+                    path: &src[2..path],
+                    desc: None,
+                },
+                path + 2,
+            ))
+        } else if src.as_bytes()[path + 1] == b'[' {
+            let desc = until_while!(src, path + 2, b']', |c| c != b']'
+                && c != b'['
+                && c != b'\n');
+
+            expect!(src, desc + 1, b']');
+
+            Some((
+                Link {
+                    path: &src[2..path],
+                    desc: Some(&src[path + 2..desc]),
+                },
+                desc + 2,
+            ))
+        } else {
+            None
+        }
+    }
+}
+
+#[test]
+fn parse() {
+    assert_eq!(
+        Link::parse("[[#id]]").unwrap(),
+        (
+            Link {
+                path: "#id",
+                desc: None,
+            },
+            "[[#id]]".len()
+        )
+    );
+    assert_eq!(
+        Link::parse("[[#id][desc]]").unwrap(),
+        (
+            Link {
+                path: "#id",
+                desc: Some("desc"),
+            },
+            "[[#id][desc]]".len()
+        )
+    );
+    assert!(Link::parse("[[#id][desc]").is_none());
+    assert!(Link::parse("[#id][desc]]").is_none());
+}