FixItApplier: Non-empty insertions can conflict with other edits

Author: AnthonyLatsis

Sources/SwiftIDEUtils/FixItApplier.swift

@@ -106,7 +106,9 @@ public enum FixItApplier {
             return false
           }
 
-          return remainingEdit.range.overlaps(edit.range)
+          // Anything else that is not disjoint bound-wise will conflict.
+          return edit.endUtf8Offset > remainingEdit.startUtf8Offset
+            && edit.startUtf8Offset < remainingEdit.endUtf8Offset
         }
 
         guard !shouldDropRemainingEdit() else {

Tests/SwiftIDEUtilsTest/FixItApplierTests.swift

@@ -202,10 +202,9 @@ class FixItApplierApplyEditsTests: XCTestCase {
         .init(range: 0..<5, replacement: "_"),  // Replacement
         .init(range: 2..<2, replacement: "a"),  // Insertion
       ],
-      // FIXME: This behavior where these edits are not considered overlapping doesn't feel desirable
       outputs: [
-        .init("_x = 1"),
-        .init("_ a= 1"),
+        .init("_ = 1"),
+        .init("vaar x = 1"),
       ]
     )
   }