Fix for paragraph style changes with mixed character styles.

This code to update the paragraph attribute removals in a way that
all the paragraph is changed when there is mixed styles in the paragraph.

Author: SergioEstevao

Aztec/Classes/Formatters/Base/ParagraphAttributeFormatter.swift

@@ -37,14 +37,14 @@ extension ParagraphAttributeFormatter {
         let rangeToApply = applicationRange(for: range, in: text)
 
         text.replaceOcurrences(of: String(.paragraphSeparator), with: String(.lineFeed), within: rangeToApply)
-        
-        text.enumerateAttributes(in: rangeToApply, options: []) { (attributes, range, stop) in
-            let currentAttributes = text.attributes(at: range.location, effectiveRange: nil)
+        // We copy the string that gets update to avoid that removal of paragraph attributes, like NSParagraphStyle,
+        // on a certain range affect all the paragraph and have side effects on the remaining removal
+        let updatedText = text.mutableCopy() as! NSMutableAttributedString
+        text.enumerateAttributes(in: rangeToApply, options: []) { (currentAttributes, range, stop) in
             let attributes = remove(from: currentAttributes)
-            
-            text.setAttributes(attributes, range: range)
+            updatedText.setAttributes(attributes, range: range)
         }
-
+        text.replaceCharacters(in: rangeToApply, with: updatedText.attributedSubstring(from: rangeToApply))
         return rangeToApply
     }
 }

Aztec/Classes/Formatters/Implementations/HeaderFormatter.swift

@@ -70,7 +70,12 @@ open class HeaderFormatter: ParagraphAttributeFormatter {
         if let font = attributes[.font] as? UIFont {
             var newFont = font.withSize(CGFloat(header.defaultFontSize))
             if Configuration.headersWithBoldTrait {
-                 newFont = newFont.modifyTraits(.traitBold, enable: false)
+                newFont = newFont.modifyTraits(.traitBold, enable: false)
+                if attributes[.shadow] != nil {
+                    resultingAttributes.removeValue(forKey: .shadow)
+                    resultingAttributes.removeValue(forKey: .kern)
+                    newFont = newFont.modifyTraits(.traitBold, enable: true)
+                }
             }
             resultingAttributes[.font] = newFont
         }
@@ -82,7 +87,9 @@ open class HeaderFormatter: ParagraphAttributeFormatter {
         guard let paragraphStyle = attributes[.paragraphStyle] as? ParagraphStyle else {
             return false
         }
-
+        if headerLevel == .none {
+            return paragraphStyle.headerLevel != 0
+        }
         return paragraphStyle.headerLevel != 0 && paragraphStyle.headerLevel == headerLevel.rawValue
     }
 }

AztecTests/TextKit/TextStorageTests.swift

@@ -538,4 +538,28 @@ class TextStorageTests: XCTestCase {
 
         XCTAssertEqual(expectedResult, result)
     }
+
+    /// Verifies that the all header formatting is removed when Header as styles (bold or italic)
+    ///
+    func testAllHeaderFormattingIsRemoved() {
+        let initialHTML = "<p>Hello World</p>"
+
+        // Setup
+        let defaultAttributes: [NSAttributedString.Key: Any] = [.font: UIFont.systemFont(ofSize: 14),
+                                                                .paragraphStyle: ParagraphStyle.default]
+        storage.setHTML(initialHTML, defaultAttributes: defaultAttributes)
+
+        let formatterH1 = HeaderFormatter(headerLevel: .h1)
+        let formatterBold = BoldWithShadowForHeadingFormatter()
+
+        formatterH1.applyAttributes(to: storage, at: NSRange(location:0, length: 0))
+        formatterBold.applyAttributes(to: storage, at: NSRange(location: 6, length: 3))
+
+        formatterH1.removeAttributes(from: storage, at: NSRange(location:0, length: 0))
+
+        storage.enumerateAttributes(in: storage.rangeOfEntireString, options: []) { (attributes, range, stop) in
+            let font = attributes[.font] as! UIFont
+            XCTAssert(font.pointSize == 14)
+        }
+    }
 }