Merge pull request #854 from notriddle/notriddle/issue-853-deeply-nes…

…ted-parens

Use same limit for refdef as inline links

pulldown-cmark/specs/regression.txt

@@ -2501,3 +2501,13 @@ ISSUE 847
 <!p>
 <p>&lt;!p&gt;</p>
 ````````````````````````````````
+
+ISSUE 853
+
+```````````````````````````````` example
+[linky]
+
+[linky]: ((()))
+.
+<p><a href="((()))">linky</a></p>
+````````````````````````````````

pulldown-cmark/src/firstpass.rs

@@ -5,7 +5,7 @@ use std::cmp::max;
 use std::ops::Range;
 
 use crate::parse::{
-    scan_containers, Allocations, FootnoteDef, HeadingAttributes, Item, ItemBody, LinkDef,
+    scan_containers, Allocations, FootnoteDef, HeadingAttributes, Item, ItemBody, LinkDef, LINK_MAX_NESTED_PARENS,
 };
 use crate::strings::CowStr;
 use crate::tree::{Tree, TreeIndex};
@@ -1678,7 +1678,7 @@ impl<'a, 'b> FirstPass<'a, 'b> {
         let (mut i, _newlines) = self.scan_refdef_space(bytes, start)?;
 
         // scan link dest
-        let (dest_length, dest) = scan_link_dest(self.text, i, 1)?;
+        let (dest_length, dest) = scan_link_dest(self.text, i, LINK_MAX_NESTED_PARENS)?;
         if dest_length == 0 {
             return None;
         }

pulldown-cmark/src/parse.rs

@@ -40,7 +40,7 @@ use crate::{Alignment, CodeBlockKind, Event, HeadingLevel, LinkType, Options, Ta
 // The simplest countermeasure is to limit their depth, which is
 // explicitly allowed by the spec as long as the limit is at least 3:
 // https://spec.commonmark.org/0.29/#link-destination
-const LINK_MAX_NESTED_PARENS: usize = 5;
+pub(crate) const LINK_MAX_NESTED_PARENS: usize = 5;
 
 #[derive(Debug, Default, Clone, Copy)]
 pub(crate) struct Item {

pulldown-cmark/tests/suite/regression.rs

@@ -2988,3 +2988,15 @@ fn regression_test_188() {
 
     test_markdown_html(original, expected, false, false, false);
 }
+
+#[test]
+fn regression_test_189() {
+    let original = r##"[linky]
+
+[linky]: ((()))
+"##;
+    let expected = r##"<p><a href="((()))">linky</a></p>
+"##;
+
+    test_markdown_html(original, expected, false, false, false);
+}