add docs.

tests/Clang/Preamble.cpp

@@ -1,6 +1,78 @@
 #include <gtest/gtest.h>
+#include <Clang/CompileDatabase.h>
+#include <Clang/Preamble.h>
+#include <Support/Filesystem.h>
+#include <clang/Lex/Preprocessor.h>
+#include <clang/Lex/MacroArgs.h>
 
-TEST(Preamble, Include) {
-    EXPECT_EQ(1, 1);
-    EXPECT_EQ(1 + 1, 2);
+// TEST(clice, preamble) {
+//     using namespace clice;
+//     CompileDatabase::instance().load("/home/ykiko/Project/C++/clice/samples/build");
+//     std::string_view path = "/home/ykiko/Project/C++/clice/samples/main.cpp";
+//     auto content = readAll(path);
+//     CompilerInvocation invocation;
+//     auto preamble = Preamble::build(path, content, invocation);
+// }
+
+TEST(clice, clang) {
+    auto instance = std::make_unique<clang::CompilerInstance>();
+
+    clang::DiagnosticIDs* ids = new clang::DiagnosticIDs();
+    clang::DiagnosticOptions* diag_opts = new clang::DiagnosticOptions();
+    clang::DiagnosticConsumer* consumer = new clang::TextDiagnosticPrinter(llvm::errs(), diag_opts);
+    clang::DiagnosticsEngine* engine = new clang::DiagnosticsEngine(ids, diag_opts, consumer);
+    instance->setDiagnostics(engine);
+
+    auto invocation = std::make_shared<clang::CompilerInvocation>();
+    std::vector<const char*> args = {
+        "-x",
+        "c++",
+        "-no-round-trip-args",
+        "-std=gnu++20",
+        "/home/ykiko/Project/C++/clice/samples/main.cpp",
+    };
+    // invocation = clang::createInvocation(args, {});
+    clang::CompilerInvocation::CreateFromArgs(*invocation, args, instance->getDiagnostics());
+    instance->setInvocation(std::move(invocation));
+
+    /// if need code completion
+    // auto& opts = invocation->getFrontendOpts();
+    // auto& codeCompletionAt = opts.CodeCompletionAt;
+    // codeCompletionAt.FileName = "main.cpp";
+    // codeCompletionAt.Line = 10;
+    // codeCompletionAt.Column = 4;
+
+    if(!instance->createTarget()) {
+        llvm::errs() << "Failed to create target\n";
+        std::terminate();
+    }
+
+    if(auto manager = instance->createFileManager()) {
+        instance->createSourceManager(*manager);
+    } else {
+        llvm::errs() << "Failed to create file manager\n";
+        std::terminate();
+    }
+
+    instance->createPreprocessor(clang::TranslationUnitKind::TU_Complete);
+
+    instance->createASTContext();
+
+    /// if code completion
+    // instance->setCodeCompletionConsumer(consumer);
+    clang::SyntaxOnlyAction action;
+
+    if(!action.BeginSourceFile(*instance, instance->getFrontendOpts().Inputs[0])) {
+        llvm::errs() << "Failed to begin source file\n";
+        std::terminate();
+    }
+
+    if(auto error = action.Execute()) {
+        llvm::errs() << "Failed to execute action: " << error << "\n";
+        std::terminate();
+    }
+
+    // instance->getASTContext().getTranslationUnitDecl()->dump();
+
+    action.EndSourceFile();
 }