Fix indexes when working with characters containing multiple unicode …

…scalars
kean · Apr 5, 2022 · 0804f33 · 0804f33
1 parent ab2800b
commit 0804f33
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Showing 2 changed files with 5 additions and 1 deletion.
diff --git a/Source/Formatting.swift b/Source/Formatting.swift
@@ -118,6 +118,9 @@ private final class Parser: NSObject, XMLParserDelegate {
         let output = NSMutableAttributedString(string: text)
         // Apply tags in reverse, more specific tags are applied last.
         for (range, attributes) in attributes.reversed() {
+            let lb = text.index(text.startIndex, offsetBy: range.lowerBound)
+            let ub = text.index(text.startIndex, offsetBy: range.upperBound)
+            let range = NSRange(lb..<ub, in: text)
             output.addAttributes(attributes, range: range)
         }
         return output

diff --git a/Tests/FormattingTests.swift b/Tests/FormattingTests.swift
@@ -198,7 +198,8 @@ class FormattingsTests: XCTestCase {
         ])
 
         // WHEN
-        let input = "⚠ Text with <t>emoji</t>"
+        // important: ⚠️ contains two unicode scalars
+        let input = "⚠️ Text with <t>emoji</t>"
         let output = NSAttributedString(formatting: input, style: style)
 
         //  THEN