Add OrgNode.find

amake · Sep 15, 2023 · 141fba5 · 141fba5
1 parent 133f47e
commit 141fba5
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diff --git a/lib/src/org.dart b/lib/src/org.dart
@@ -38,6 +38,8 @@ String parseOrgIdUrl(String url) {
   return url.substring(3);
 }
 
+typedef OrgPath = List<OrgNode>;
+
 /// The base type of all Org AST objects
 abstract class OrgNode {
   /// The children of this node. May be empty (no children) or null (an object
@@ -68,6 +70,25 @@ abstract class OrgNode {
     return true;
   }
 
+  ({T node, OrgPath path})? find<T extends OrgNode>(
+    bool Function(T) predicate, [
+    OrgPath path = const [],
+  ]) {
+    final self = this;
+    if (self is T && predicate(self)) {
+      return (node: self, path: path);
+    }
+    if (children != null) {
+      for (final child in children!) {
+        final result = child.find<T>(predicate, [...path, child]);
+        if (result != null) {
+          return result;
+        }
+      }
+    }
+    return null;
+  }
+
   String toMarkup() {
     final buf = StringBuffer();
     _toMarkupImpl(buf);

diff --git a/test/ast_test.dart b/test/ast_test.dart
@@ -522,6 +522,51 @@ content''');
         expect(sections, ['Foobar', 'Bizzbazz']);
       });
     });
+    group('find', () {
+      final result = parser.parse('''* Foobar
+** Bizzbazz
+/boo/
+*** Bingbang
+*blah*''');
+      final doc = result.value as OrgDocument;
+      test('find deep with type', () {
+        var visited = 0;
+        final found = doc.find<OrgMarkup>((node) {
+          visited += 1;
+          return node.style == OrgStyle.bold;
+        });
+        expect(found, isNotNull);
+        expect(found!.node.content, 'blah');
+        expect(visited, 2);
+        expect(found.path.map((n) => n.toString()), [
+          'OrgSection',
+          'OrgSection',
+          'OrgSection',
+          'OrgContent',
+          'OrgParagraph',
+          'OrgContent',
+          'OrgMarkup'
+        ]);
+      });
+      test('find shallow with type', () {
+        var visited = 0;
+        final found = doc.find<OrgMarkup>((node) {
+          visited += 1;
+          return node.style == OrgStyle.italic;
+        });
+        expect(found, isNotNull);
+        expect(found!.node.content, 'boo');
+        expect(visited, 1);
+        expect(found.path.map((n) => n.toString()), [
+          'OrgSection',
+          'OrgSection',
+          'OrgContent',
+          'OrgParagraph',
+          'OrgContent',
+          'OrgMarkup'
+        ]);
+      });
+    });
     group('section ids', () {
       test('has ids', () {
         final result = parser.parse('''* Foobar