xref: /llvm-project/clang/unittests/Analysis/FlowSensitive/ASTOpsTest.cpp (revision 198fb5ed4ac7d096da03ea4a0a27832d18b1350f)
1 //===- unittests/Analysis/FlowSensitive/ASTOpsTest.cpp --------------------===//
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 "clang/Analysis/FlowSensitive/ASTOps.h"
10 #include "TestingSupport.h"
11 #include "clang/AST/Decl.h"
12 #include "clang/AST/DeclCXX.h"
13 #include "clang/ASTMatchers/ASTMatchers.h"
14 #include "clang/Basic/LLVM.h"
15 #include "clang/Frontend/ASTUnit.h"
16 #include "clang/Tooling/Tooling.h"
17 #include "gmock/gmock.h"
18 #include "gtest/gtest.h"
19 #include <memory>
20 #include <string>
21 
22 namespace {
23 
24 using namespace clang;
25 using namespace dataflow;
26 
27 using ast_matchers::cxxMethodDecl;
28 using ast_matchers::cxxRecordDecl;
29 using ast_matchers::hasName;
30 using ast_matchers::hasType;
31 using ast_matchers::initListExpr;
32 using ast_matchers::match;
33 using ast_matchers::selectFirst;
34 using test::findValueDecl;
35 using testing::IsEmpty;
36 using testing::UnorderedElementsAre;
37 
38 TEST(ASTOpsTest, RecordInitListHelperOnEmptyUnionInitList) {
39   // This is a regression test: The `RecordInitListHelper` used to assert-fail
40   // when called for the `InitListExpr` of an empty union.
41   std::string Code = R"cc(
42     struct S {
43       S() : UField{} {};
44 
45       union U {} UField;
46     };
47   )cc";
48   std::unique_ptr<ASTUnit> Unit =
49       tooling::buildASTFromCodeWithArgs(Code, {"-fsyntax-only", "-std=c++17"});
50   auto &ASTCtx = Unit->getASTContext();
51 
52   ASSERT_EQ(ASTCtx.getDiagnostics().getClient()->getNumErrors(), 0U);
53 
54   auto *InitList = selectFirst<InitListExpr>(
55       "init",
56       match(initListExpr(hasType(cxxRecordDecl(hasName("U")))).bind("init"),
57             ASTCtx));
58   ASSERT_NE(InitList, nullptr);
59 
60   RecordInitListHelper Helper(InitList);
61   EXPECT_THAT(Helper.base_inits(), IsEmpty());
62   EXPECT_THAT(Helper.field_inits(), IsEmpty());
63 }
64 
65 TEST(ASTOpsTest, ReferencedDeclsOnUnionInitList) {
66   // This is a regression test: `getReferencedDecls()` used to return a null
67   // `FieldDecl` in this case (in addition to the correct non-null `FieldDecl`)
68   // because `getInitializedFieldInUnion()` returns null for the syntactic form
69   // of the `InitListExpr`.
70   std::string Code = R"cc(
71     struct S {
72       S() : UField{0} {};
73 
74       union U {
75         int I;
76       } UField;
77     };
78   )cc";
79   std::unique_ptr<ASTUnit> Unit =
80       tooling::buildASTFromCodeWithArgs(Code, {"-fsyntax-only", "-std=c++17"});
81   auto &ASTCtx = Unit->getASTContext();
82 
83   ASSERT_EQ(ASTCtx.getDiagnostics().getClient()->getNumErrors(), 0U);
84 
85   auto *InitList = selectFirst<InitListExpr>(
86       "init",
87       match(initListExpr(hasType(cxxRecordDecl(hasName("U")))).bind("init"),
88             ASTCtx));
89   ASSERT_NE(InitList, nullptr);
90   auto *IDecl = cast<FieldDecl>(findValueDecl(ASTCtx, "I"));
91 
92   EXPECT_THAT(getReferencedDecls(*InitList).Fields,
93               UnorderedElementsAre(IDecl));
94 }
95 
96 TEST(ASTOpsTest, ReferencedDeclsLocalsNotParamsOrStatics) {
97   std::string Code = R"cc(
98     void func(int Param) {
99       static int Static = 0;
100       int Local = Param;
101       Local = Static;
102     }
103   )cc";
104   std::unique_ptr<ASTUnit> Unit =
105       tooling::buildASTFromCodeWithArgs(Code, {"-fsyntax-only", "-std=c++17"});
106   auto &ASTCtx = Unit->getASTContext();
107 
108   ASSERT_EQ(ASTCtx.getDiagnostics().getClient()->getNumErrors(), 0U);
109 
110   auto *Func = cast<FunctionDecl>(findValueDecl(ASTCtx, "func"));
111   ASSERT_NE(Func, nullptr);
112   auto *LocalDecl = cast<VarDecl>(findValueDecl(ASTCtx, "Local"));
113 
114   EXPECT_THAT(getReferencedDecls(*Func).Locals,
115               UnorderedElementsAre(LocalDecl));
116 }
117 
118 TEST(ASTOpsTest, LambdaCaptures) {
119   std::string Code = R"cc(
120     void func(int CapturedByRef, int CapturedByValue, int NotCaptured) {
121     int Local;
122       auto Lambda = [&CapturedByRef, CapturedByValue, &Local](int LambdaParam) {
123       };
124     }
125   )cc";
126   std::unique_ptr<ASTUnit> Unit =
127       tooling::buildASTFromCodeWithArgs(Code, {"-fsyntax-only", "-std=c++17"});
128   auto &ASTCtx = Unit->getASTContext();
129 
130   ASSERT_EQ(ASTCtx.getDiagnostics().getClient()->getNumErrors(), 0U);
131 
132   auto *LambdaCallOp = selectFirst<CXXMethodDecl>(
133       "l", match(cxxMethodDecl(hasName("operator()")).bind("l"), ASTCtx));
134   ASSERT_NE(LambdaCallOp, nullptr);
135   auto *Func = cast<FunctionDecl>(findValueDecl(ASTCtx, "func"));
136   ASSERT_NE(Func, nullptr);
137   auto *CapturedByRefDecl = Func->getParamDecl(0);
138   ASSERT_NE(CapturedByRefDecl, nullptr);
139   auto *CapturedByValueDecl = Func->getParamDecl(1);
140   ASSERT_NE(CapturedByValueDecl, nullptr);
141 
142   EXPECT_THAT(getReferencedDecls(*Func).LambdaCapturedParams, IsEmpty());
143   ReferencedDecls ForLambda = getReferencedDecls(*LambdaCallOp);
144   EXPECT_THAT(ForLambda.LambdaCapturedParams,
145               UnorderedElementsAre(CapturedByRefDecl, CapturedByValueDecl));
146   // Captured locals must be seen in the body for them to appear in
147   // ReferencedDecls.
148   EXPECT_THAT(ForLambda.Locals, IsEmpty());
149 }
150 
151 } // namespace
152