LanguageServer/Cpp: Add tests

The Cpp LanguageServer tests can be run with: CppLanguageServer -t

The tests now only cover some very simple autocomplete and
"find declaration" use cases, but it's a start :)

4 files changed, 165 insertions, 1 deletions

diff --git a/Userland/DevTools/HackStudio/LanguageServers/Cpp/CMakeLists.txt b/Userland/DevTools/HackStudio/LanguageServers/Cpp/CMakeLists.txt
index 55f6995844..a6c405548d 100644
--- a/Userland/DevTools/HackStudio/LanguageServers/Cpp/CMakeLists.txt
+++ b/Userland/DevTools/HackStudio/LanguageServers/Cpp/CMakeLists.txt
@@ -1,6 +1,7 @@
 set(SOURCES
     LexerAutoComplete.cpp
     ParserAutoComplete.cpp
+    Tests.cpp
     main.cpp
 )
 
diff --git a/Userland/DevTools/HackStudio/LanguageServers/Cpp/Tests.cpp b/Userland/DevTools/HackStudio/LanguageServers/Cpp/Tests.cpp
new file mode 100644
index 0000000000..a76855a96e
--- /dev/null
+++ b/Userland/DevTools/HackStudio/LanguageServers/Cpp/Tests.cpp
@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) 2021, Itamar S. <itamar8910@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "Tests.h"
+#include "../FileDB.h"
+#include "ParserAutoComplete.h"
+
+using namespace LanguageServers;
+using namespace LanguageServers::Cpp;
+
+static bool s_some_test_failed = false;
+
+#define I_TEST(name)                     \
+    {                                    \
+        printf("Testing " #name "... "); \
+        fflush(stdout);                  \
+    }
+
+#define PASS              \
+    do {                  \
+        printf("PASS\n"); \
+        fflush(stdout);   \
+        return;           \
+    } while (0)
+
+#define FAIL(reason)                   \
+    do {                               \
+        printf("FAIL: " #reason "\n"); \
+        s_some_test_failed = true;     \
+        return;                        \
+    } while (0)
+
+static void test_complete_local_args();
+static void test_complete_local_vars();
+static void test_complete_type();
+static void test_find_variable_definition();
+
+int run_tests()
+{
+    test_complete_local_args();
+    test_complete_local_vars();
+    test_complete_type();
+    test_find_variable_definition();
+    return s_some_test_failed ? 1 : 0;
+}
+
+void test_complete_local_args()
+{
+    I_TEST(Complete Local Args)
+    FileDB filedb;
+    String content = R"(
+int main(int argc, char** argv){
+ar
+}
+)";
+    filedb.add("a.cpp", content);
+    ParserAutoComplete autocomplete(filedb);
+    auto suggestions = autocomplete.get_suggestions("a.cpp", { 2, 2 });
+    if (suggestions.size() != 2)
+        FAIL(bad size);
+
+    if (suggestions[0].completion == "argc" && suggestions[1].completion == "argv")
+        PASS;
+
+    FAIL("wrong results");
+}
+
+void test_complete_local_vars()
+{
+    I_TEST(Complete Local Vars)
+    FileDB filedb;
+    String content = R"(
+int main(int argc, char** argv){
+int myvar1 = 3;
+myv
+}
+)";
+    filedb.add("a.cpp", content);
+    ParserAutoComplete autocomplete(filedb);
+    auto suggestions = autocomplete.get_suggestions("a.cpp", { 3, 3 });
+    if (suggestions.size() != 1)
+        FAIL(bad size);
+
+    if (suggestions[0].completion == "myvar1")
+        PASS;
+
+    FAIL("wrong results");
+}
+
+void test_complete_type()
+{
+    I_TEST(Complete Type)
+    FileDB filedb;
+    String content = R"(
+struct MyStruct {
+int x;
+}
+void foo(){
+MyS
+}
+)";
+    filedb.add("a.cpp", content);
+    ParserAutoComplete autocomplete(filedb);
+    auto suggestions = autocomplete.get_suggestions("a.cpp", { 5, 3 });
+    if (suggestions.size() != 1)
+        FAIL(bad size);
+
+    if (suggestions[0].completion == "MyStruct")
+        PASS;
+
+    FAIL("wrong results");
+}
+
+void test_find_variable_definition()
+{
+    I_TEST(Find Variable Declaration)
+    FileDB filedb;
+    String content = R"(
+int main(int argc, char** argv){
+argv = nullptr;
+}
+)";
+    filedb.add("a.cpp", content);
+    ParserAutoComplete autocomplete(filedb);
+    auto position = autocomplete.find_declaration_of("a.cpp", { 2, 1 });
+    if (!position.has_value())
+        FAIL("declaration not found");
+
+    if (position.value().file == "a.cpp" && position.value().line == 1 && position.value().column >= 19)
+        PASS;
+    FAIL("wrong declaration location");
+}
diff --git a/Userland/DevTools/HackStudio/LanguageServers/Cpp/Tests.h b/Userland/DevTools/HackStudio/LanguageServers/Cpp/Tests.h
new file mode 100644
index 0000000000..0c98313e9a
--- /dev/null
+++ b/Userland/DevTools/HackStudio/LanguageServers/Cpp/Tests.h
@@ -0,0 +1,9 @@
+/*
+ * Copyright (c) 2021, Itamar S. <itamar8910@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+int run_tests();
diff --git a/Userland/DevTools/HackStudio/LanguageServers/Cpp/main.cpp b/Userland/DevTools/HackStudio/LanguageServers/Cpp/main.cpp
index a13c424f26..6e404c6af7 100644
--- a/Userland/DevTools/HackStudio/LanguageServers/Cpp/main.cpp
+++ b/Userland/DevTools/HackStudio/LanguageServers/Cpp/main.cpp
@@ -5,7 +5,9 @@
  */
 
 #include "ClientConnection.h"
+#include "Tests.h"
 #include <AK/LexicalPath.h>
+#include <LibCore/ArgsParser.h>
 #include <LibCore/EventLoop.h>
 #include <LibCore/File.h>
 #include <LibCore/LocalServer.h>
@@ -13,7 +15,24 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
-int main(int, char**)
+static int mode_server();
+
+int main(int argc, char** argv)
+{
+    bool tests = false;
+
+    Core::ArgsParser parser;
+    parser.add_option(tests, "Run tests", "tests", 't');
+    parser.parse(argc, argv);
+
+    if (tests) {
+        return run_tests();
+    }
+
+    return mode_server();
+}
+
+int mode_server()
 {
     Core::EventLoop event_loop;
     if (pledge("stdio unix recvfd rpath ", nullptr) < 0) {