Support converting Markdown into a string without any markup.

Author: objecthub

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## 1.1.9 (2024-08-04)
+
+- Support converting Markdown into a string without any markup
+
 ## 1.1.8 (2024-05-01)
 - Fix `Color.hexString` on iOS to handle black correctly
 - Clean up `Package.swift`

Sources/MarkdownKit/Block.swift

@@ -141,6 +141,42 @@ public enum Block: Equatable, CustomStringConvertible, CustomDebugStringConverti
         return self.description
     }
   }
+  
+  /// Returns raw text for this block, i.e. ignoring all markup.
+  public var string: String {
+    switch self {
+      case .document(let blocks):
+        return blocks.string
+      case .blockquote(let blocks):
+        return blocks.string
+      case .list(_, _, let blocks):
+        return blocks.string
+      case .listItem(_, _, let blocks):
+        return blocks.string
+      case .paragraph(let text):
+        return text.string
+      case .heading(_, let text):
+        return text.string
+      case .indentedCode(let lines):
+        return lines.map { String($0) }.joined()
+      case .fencedCode(_, let lines):
+        return lines.map { String($0) }.joined(separator: "\n")
+      case .htmlBlock(_):
+        return ""
+      case .referenceDef(_, _, let lines):
+        return lines.map { String($0) }.joined(separator: " ")
+      case .thematicBreak:
+        return "\n\n"
+      case .table(let headers, _, let rows):
+        return headers.map { $0.string }.joined(separator: " | ") + "\n" +
+               rows.map { $0.map { $0.string }.joined(separator: " | ") }
+                   .joined(separator: "\n")
+      case .definitionList(let defs):
+        return defs.map { $0.string }.joined(separator: "\n\n")
+      case .custom(let obj):
+        return obj.string
+    }
+  }
 
   fileprivate static func string(from blocks: Blocks) -> String {
     var res = ""
@@ -295,6 +331,10 @@ public struct Definition: Equatable, CustomStringConvertible, CustomDebugStringC
   public var debugDescription: String {
     return self.description
   }
+  
+  public var string: String {
+    return "\(self.item.rawDescription): \(self.descriptions.string)"
+  }
 }
 
 public typealias Definitions = ContiguousArray<Definition>

Sources/MarkdownKit/Blocks.swift

@@ -43,4 +43,9 @@ extension Blocks {
   public var isSingleton: Bool {
     return self.count == 1
   }
+  
+  /// Returns raw text for this sequence of blocks.
+  public var string: String {
+    return self.map { $0.string }.joined(separator: "\n")
+  }
 }

Sources/MarkdownKit/CustomBlock.swift

@@ -25,6 +25,7 @@ import Foundation
 /// externally (i.e. not by the MarkdownKit framework).
 ///
 public protocol CustomBlock: CustomStringConvertible, CustomDebugStringConvertible {
+  var string: String { get }
   func equals(to other: CustomBlock) -> Bool
   func parse(via parser: InlineParser) -> Block
   func generateHtml(via htmlGen: HtmlGenerator, tight: Bool) -> String
@@ -34,3 +35,10 @@ public protocol CustomBlock: CustomStringConvertible, CustomDebugStringConvertib
                     tight: Bool) -> String
   #endif
 }
+
+extension CustomBlock {
+  /// By default, the custom block does not have any raw string content.
+  public var string: String {
+    return ""
+  }
+}

Sources/MarkdownKit/Text.swift

@@ -126,13 +126,15 @@ public struct Text: Collection, Equatable, CustomStringConvertible, CustomDebugS
   /// Returns a raw description of this `Text` object as a string, i.e. as if the text
   /// would be represented in Markdown but ignoring all markup.
   public var rawDescription: String {
-    var res = ""
-    for fragment in self.fragments {
-      res = res + fragment.rawDescription
-    }
-    return res
+    return self.fragments.map { $0.rawDescription }.joined()
   }
-
+  
+  /// Returns a raw description of this `Text` object as a string for which all markup
+  /// gets ignored.
+  public var string: String {
+    return self.fragments.map { $0.string }.joined()
+  }
+  
   /// Returns a debug description of this `Text` object.
   public var debugDescription: String {
     var res = ""

Sources/MarkdownKit/TextFragment.swift

@@ -108,7 +108,24 @@ public enum TextFragment: Equatable, CustomStringConvertible, CustomDebugStringC
         return customTextFragment.rawDescription
     }
   }
-
+  
+  /// Returns a raw description of this `TextFragment` object as a string in which all
+  /// markup gets ignored.
+  public var string: String {
+    switch self {
+      case .html(_):
+        return ""
+      case .delimiter(let ch, let n, _):
+        var res = String(ch)
+        for _ in 1..<n {
+          res.append(ch)
+        }
+        return res
+      default:
+        return self.rawDescription
+    }
+  }
+  
   /// Returns a debug description of this `TextFragment` object.
   public var debugDescription: String {
     switch self {

Tests/MarkdownKitTests/MarkdownBlockTests.swift

@@ -325,6 +325,14 @@ class MarkdownBlockTests: XCTestCase, MarkdownKitFactory {
                                       "</code></pre>\n"),
                             paragraph("okay")))
   }
+  
+  func testToString() {
+    XCTAssertEqual(parseBlocks(" # First\n ## Second  \n### Third").string, "First\nSecond\nThird")
+    XCTAssertEqual(parseBlocks(">  # Hello\n>  Next line\n And last line").string, "Hello\nNext line And last line")
+    XCTAssertEqual(parseBlocks("one\n\n      foo\n    bar\n\ntwo").string, "one\n  foo\nbar\n\ntwo")
+    XCTAssertEqual(parseBlocks("- foo\n - bar\n  - baz\n   - boo").string, "foo\nbar\nbaz\nboo")
+    XCTAssertEqual(parseBlocks("- foo\n  - one\n  - two\n \n  three").string, "foo\none\ntwo\nthree")
+  }
 
   func testDebug() {