[clang] [clang][dataflow] Fully support Environment construction for Stmt analysis. (PR #91616)

[via cfe-commits]

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@@ -146,6 +146,30 @@ TEST_F(DataflowAnalysisTest, DiagnoseFunctionDiagnoserCalledOnEachElement) {
                                    " (Lifetime ends)\n")));
 }
 
+TEST_F(DataflowAnalysisTest, CanAnalyzeStmt) {
+  std::string Code = R"cc(
+      struct S {int i;};
+      S getAnS() {return S{1};};
+      void foo() {
+        S AnS = getAnS();
+      }
+    )cc";
+  AST = tooling::buildASTFromCodeWithArgs(Code, {"-std=c++11"});
+  const auto &DeclStatement = matchNode<DeclStmt>(declStmt());
+  const auto &Func = matchNode<FunctionDecl>(functionDecl(hasName("foo")));
+
+  ACFG = std::make_unique<AdornedCFG>(llvm::cantFail(AdornedCFG::build(
+      Func, const_cast<DeclStmt &>(DeclStatement), AST->getASTContext())));
+
+  NoopAnalysis Analysis = NoopAnalysis(AST->getASTContext());
+  DACtx = std::make_unique<DataflowAnalysisContext>(
+      std::make_unique<WatchedLiteralsSolver>());
+  Environment Env(*DACtx, const_cast<DeclStmt &>(DeclStatement));
+
+  ASSERT_THAT_ERROR(runDataflowAnalysis(*ACFG, Analysis, Env).takeError(),
+                    llvm::Succeeded());
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martinboehme wrote:

Again, can we make this test stronger than simply asserting that we don't error out?

For example, if we made the member variable of `S` a bool instead of an integer, we could verify that it was initialized with a specific boolean literal.

https://github.com/llvm/llvm-project/pull/91616