1 //===- llvm/unittest/Support/EditDistanceTest.cpp - Edit distance tests ---===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/ADT/StringRef.h"
10 #include "llvm/ADT/edit_distance.h"
11 #include "gtest/gtest.h"
12 #include <cstdlib>
13 
14 using namespace llvm;
15 
16 namespace {
17 
18 struct Result {
19   unsigned NumMaps;
20   unsigned EditDist;
21 };
22 } // namespace
23 
24 static Result editDistanceAndMaps(StringRef A, StringRef B,
25                                   unsigned MaxEditDistance = 0) {
26   unsigned NumMaps = 0;
27   auto TrackMaps = [&](const char X) {
28     ++NumMaps;
29     return X;
30   };
31   unsigned EditDist = llvm::ComputeMappedEditDistance(
32       makeArrayRef(A.data(), A.size()), makeArrayRef(B.data(), B.size()),
33       TrackMaps, true, MaxEditDistance);
34   return {NumMaps, EditDist};
35 }
36 
37 TEST(EditDistance, VerifyShortCircuit) {
38   StringRef Hello = "Hello";
39   StringRef HelloWorld = "HelloWorld";
40   Result R = editDistanceAndMaps(Hello, HelloWorld, 5);
41   EXPECT_EQ(R.EditDist, 5U);
42   EXPECT_GT(R.NumMaps, 0U);
43 
44   R = editDistanceAndMaps(Hello, HelloWorld);
45   EXPECT_EQ(R.EditDist, 5U);
46   EXPECT_GT(R.NumMaps, 0U);
47 
48   R = editDistanceAndMaps(Hello, HelloWorld, 4);
49   EXPECT_EQ(R.EditDist, 5U);
50   EXPECT_EQ(R.NumMaps, 0U);
51 
52   R = editDistanceAndMaps(HelloWorld, Hello, 4);
53   EXPECT_EQ(R.EditDist, 5U);
54   EXPECT_EQ(R.NumMaps, 0U);
55 
56   R = editDistanceAndMaps(Hello, HelloWorld, 1);
57   EXPECT_EQ(R.EditDist, 2U);
58   EXPECT_EQ(R.NumMaps, 0U);
59 
60   R = editDistanceAndMaps(HelloWorld, Hello, 1);
61   EXPECT_EQ(R.EditDist, 2U);
62   EXPECT_EQ(R.NumMaps, 0U);
63 }
64