Fix blankLinesAroundMark not ignoring trailing comments at start of scope (#2203)

Author: mattczech

Sources/Rules/BlankLinesAroundMark.swift

@@ -28,7 +28,7 @@ public extension FormatRule {
             }
             if formatter.options.insertBlankLines,
                let lastIndex = formatter.index(of: .linebreak, before: startIndex),
-               let lastToken = formatter.last(.nonSpace, before: lastIndex),
+               let lastToken = formatter.last(.nonSpaceOrComment, before: lastIndex),
                !lastToken.isLinebreak, lastToken != .startOfScope("{")
             {
                 formatter.insertLinebreak(at: lastIndex)

Tests/Rules/BlankLinesAroundMarkTests.swift

@@ -74,6 +74,17 @@ class BlankLinesAroundMarkTests: XCTestCase {
         testFormatting(for: input, rule: .blankLinesAroundMark)
     }
 
+    func testNoInsertBlankLineBeforeMarkAtStartOfScopeWithTrailingComment() {
+        let input = """
+        struct Foo { // some comment here
+            // MARK: bar
+
+            let string: String
+        }
+        """
+        testFormatting(for: input, rule: .blankLinesAroundMark)
+    }
+
     func testNoInsertBlankLineAfterMarkAtEndOfScope() {
         let input = """
         do {