1//===- unittests/ErrorOrTest.cpp - ErrorOr.h 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/Support/ErrorOr.h"
10#include "llvm/Support/Errc.h"
11#include "gtest/gtest.h"
12#include <memory>
13
14using namespace llvm;
15
16namespace {
17
18ErrorOr<int> t1() { return 1; }
19ErrorOr<int> t2() { return errc::invalid_argument; }
20
21TEST(ErrorOr, SimpleValue) {
22 ErrorOr<int> a = t1();
23 // FIXME: This is probably a bug in gtest. EXPECT_TRUE should expand to
24 // include the !! to make it friendly to explicit bool operators.
25 EXPECT_TRUE(!!a);
26 EXPECT_EQ(1, *a);
27
28 ErrorOr<int> b = a;
29 EXPECT_EQ(1, *b);
30
31 a = t2();
32 EXPECT_FALSE(a);
33 EXPECT_EQ(a.getError(), errc::invalid_argument);
34#ifdef EXPECT_DEBUG_DEATH
35 EXPECT_DEBUG_DEATH(*a, "Cannot get value when an error exists");
36#endif
37}
38
39ErrorOr<std::unique_ptr<int> > t3() {
40 return std::unique_ptr<int>(new int(3));
41}
42
43TEST(ErrorOr, Types) {
44 int x;
45 ErrorOr<int&> a(x);
46 *a = 42;
47 EXPECT_EQ(42, x);
48
49 // Move only types.
50 EXPECT_EQ(3, **t3());
51}
52
53struct B {};
54struct D : B {};
55
56TEST(ErrorOr, Covariant) {
57 ErrorOr<B*> b(ErrorOr<D*>(nullptr));
58 b = ErrorOr<D*>(nullptr);
59
60 ErrorOr<std::unique_ptr<B> > b1(ErrorOr<std::unique_ptr<D> >(nullptr));
61 b1 = ErrorOr<std::unique_ptr<D> >(nullptr);
62
63 ErrorOr<std::unique_ptr<int>> b2(ErrorOr<int *>(nullptr));
64 ErrorOr<int *> b3(nullptr);
65 ErrorOr<std::unique_ptr<int>> b4(b3);
66}
67
68TEST(ErrorOr, Comparison) {
69 ErrorOr<int> x(errc::no_such_file_or_directory);
70 EXPECT_EQ(x, errc::no_such_file_or_directory);
71}
72
73TEST(ErrorOr, ImplicitConversion) {
74 ErrorOr<std::string> x("string literal");
75 EXPECT_TRUE(!!x);
76}
77
78TEST(ErrorOr, ImplicitConversionCausesMove) {
79 struct Source {};
80 struct Destination {
81 Destination(const Source&) {}
82 Destination(Source&&) = delete;
83 };
84 Source s;
85 ErrorOr<Destination> x = s;
86 EXPECT_TRUE(!!x);
87}
88
89TEST(ErrorOr, ImplicitConversionNoAmbiguity) {
90 struct CastsToErrorCode {
91 CastsToErrorCode() = default;
92 CastsToErrorCode(std::error_code) {}
93 operator std::error_code() { return errc::invalid_argument; }
94 } casts_to_error_code;
95 ErrorOr<CastsToErrorCode> x1(casts_to_error_code);
96 ErrorOr<CastsToErrorCode> x2 = casts_to_error_code;
97 ErrorOr<CastsToErrorCode> x3 = {casts_to_error_code};
98 ErrorOr<CastsToErrorCode> x4{casts_to_error_code};
99 ErrorOr<CastsToErrorCode> x5(errc::no_such_file_or_directory);
100 ErrorOr<CastsToErrorCode> x6 = errc::no_such_file_or_directory;
101 ErrorOr<CastsToErrorCode> x7 = {errc::no_such_file_or_directory};
102 ErrorOr<CastsToErrorCode> x8{errc::no_such_file_or_directory};
103 EXPECT_TRUE(!!x1);
104 EXPECT_TRUE(!!x2);
105 EXPECT_TRUE(!!x3);
106 EXPECT_TRUE(!!x4);
107 EXPECT_FALSE(x5);
108 EXPECT_FALSE(x6);
109 EXPECT_FALSE(x7);
110 EXPECT_FALSE(x8);
111}
112
113// ErrorOr<int*> x(nullptr);
114// ErrorOr<std::unique_ptr<int>> y = x; // invalid conversion
115static_assert(
116 !std::is_convertible_v<const ErrorOr<int *> &,
117 ErrorOr<std::unique_ptr<int>>>,
118 "do not invoke explicit ctors in implicit conversion from lvalue");
119
120// ErrorOr<std::unique_ptr<int>> y = ErrorOr<int*>(nullptr); // invalid
121// // conversion
122static_assert(
123 !std::is_convertible_v<ErrorOr<int *> &&, ErrorOr<std::unique_ptr<int>>>,
124 "do not invoke explicit ctors in implicit conversion from rvalue");
125
126// ErrorOr<int*> x(nullptr);
127// ErrorOr<std::unique_ptr<int>> y;
128// y = x; // invalid conversion
129static_assert(!std::is_assignable_v<ErrorOr<std::unique_ptr<int>> &,
130 const ErrorOr<int *> &>,
131 "do not invoke explicit ctors in assignment");
132
133// ErrorOr<std::unique_ptr<int>> x;
134// x = ErrorOr<int*>(nullptr); // invalid conversion
135static_assert(
136 !std::is_assignable_v<ErrorOr<std::unique_ptr<int>> &, ErrorOr<int *> &&>,
137 "do not invoke explicit ctors in assignment");
138} // end anon namespace
139

source code of llvm/unittests/Support/ErrorOrTest.cpp