Add gtest

Signed-off-by: CHatingPython <chatingpython@gmail.com>

furc/test/lexer.cpp

@@ -0,0 +1,29 @@
+#include "furc/front/lexer.hpp"
+
+#include "gtest/gtest.h"
+
+namespace {
+
+using namespace furc::front;
+using namespace std::string_view_literals;
+
+#define EXPECT_TOKEN(lexer, t) EXPECT_EQ((lexer).next_token(), (t));
+
+TEST(Lexer, Tokens) {
+    lexer lexer("<TEMP>", "()\n\t\t{\n}[];    :,.main return func");
+    EXPECT_TOKEN(lexer, (token{ token_t::Lparen, "("sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Rparen, ")"sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Lbrace, "{"sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Rbrace, "}"sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Lbracket, "["sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Rbracket, "]"sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Semicolon, ";"sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Colon, ":"sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Comma, ","sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Dot, "."sv }));
+    EXPECT_TOKEN(lexer, (token{ token_t::Identifier, "main"sv }));
+    EXPECT_TOKEN(lexer, (token{ keyword_token::Return }));
+    EXPECT_TOKEN(lexer, (token{ keyword_token::Func }));
+}
+
+} // namespace