Add tests for replacing the entire base collection

Author: karwa

Tests/SwiftAlgorithmsTests/ReplaceSubrangeTests.swift

@@ -176,5 +176,23 @@ final class ReplaceSubrangeTests: XCTestCase {
       XCTAssertEqualCollections(result, "hello, wo")
       IndexValidator().validate(result, expectedCount: 9)
     }
+
+    // Location: entire collection
+    // Replacement: non-empty
+    do {
+      let base = "hello, world!"
+      let result = base.lazy.replacingSubrange(base.startIndex..<base.endIndex, with: Array("blah blah blah"))
+      XCTAssertEqualCollections(result, "blah blah blah")
+      IndexValidator().validate(result, expectedCount: 14)
+    }
+
+    // Location: entire collection
+    // Replacement: empty
+    do {
+      let base = "hello, world!"
+      let result = base.lazy.replacingSubrange(base.startIndex..<base.endIndex, with: EmptyCollection())
+      XCTAssertEqualCollections(result, "")
+      IndexValidator().validate(result, expectedCount: 0)
+    }
   }
 }