From 39ac8ef02d765b461650d59a4e835ae862199d47 Mon Sep 17 00:00:00 2001
From: eelke <eelke@eelkeklein.nl>
Date: Mon, 28 Jan 2019 20:53:10 +0100
Subject: [PATCH] Some work on parser, not used yet.

---
 core/SqlAstSelect.cpp              | 11 +++++++----
 core/SqlParser.cpp                 |  9 +++++++--
 core/SqlParser.h                   |  4 +++-
 tests/pglabtests/pglabtests.pro    |  5 +++--
 tests/pglabtests/tst_SqlParser.cpp | 30 ++++++++++++++++++++++++++++++
 5 files changed, 50 insertions(+), 9 deletions(-)
 create mode 100644 tests/pglabtests/tst_SqlParser.cpp

diff --git a/core/SqlAstSelect.cpp b/core/SqlAstSelect.cpp
index dcf7a5a..001bedd 100644
--- a/core/SqlAstSelect.cpp
+++ b/core/SqlAstSelect.cpp
@@ -2,16 +2,19 @@
 #include "SqlAstSelectList.h"
 #include "SqlParser.h"
 
-using namespace SqlAst;
+namespace SqlAst {
+
 
 std::shared_ptr<SqlAst::Select> parseSelect(SqlParser &parser)
 {
-	std::shared_ptr<SqlAst::Select> ast_select = std::make_shared<SqlAst::Select>();
+	auto ast_select = std::make_shared<SqlAst::Select>();
 	// parse select list of expression + aliasses, required
-	auto select_list = parseSelectList(parser);
-	ast_select->setSelectList(select_list);
+//	auto select_list = parseSelectList(parser);
+//	ast_select->setSelectList(select_list);
 
 	// parse optional from list
 
 	return ast_select;
 }
+
+}
diff --git a/core/SqlParser.cpp b/core/SqlParser.cpp
index e14e7f0..38354bd 100644
--- a/core/SqlParser.cpp
+++ b/core/SqlParser.cpp
@@ -33,7 +33,7 @@ SqlParser::SqlParser(SqlLexer &lexer)
 
 }
 
-void SqlParser::parse()
+std::shared_ptr<SqlAst::Node> SqlParser::parse()
 {
 	// Basic algo:
 	// LOOP
@@ -41,6 +41,7 @@ void SqlParser::parse()
 	//   IF NOT try_reduce(token)
 	//   THEN SHIFT
 	// END LOOP
+	std::shared_ptr<SqlAst::Node> result;
 	while (true) {
 		SqlToken token = lexer.nextBasicToken();
 		if (token.ok) {
@@ -57,10 +58,14 @@ void SqlParser::parse()
 					break;
 				}
 			}
+			else if (token.tokenType == BasicTokenType::End) {
+				// Are we at the top level?
+				return result;
+			}
 		}
 		else {
 			// error during lexical analysis, need to recover
-
+			throw std::runtime_error("Unrecognized input");
 		}
 	}
 }
diff --git a/core/SqlParser.h b/core/SqlParser.h
index 621675b..b5e9dad 100644
--- a/core/SqlParser.h
+++ b/core/SqlParser.h
@@ -2,6 +2,7 @@
 #define SQLPARSER_H
 
 #include "SqlLexer.h"
+#include "SqlAstNode.h"
 #include <memory>
 #include <optional>
 
@@ -22,6 +23,7 @@ enum class Keyword {
 
 namespace SqlAst {
 
+	class Node;
 	class Select;
 	class SelectList;
 
@@ -37,7 +39,7 @@ class SqlParser
 public:
 	explicit SqlParser(SqlLexer &lexer);
 
-	void parse();
+	std::shared_ptr<SqlAst::Node> parse();
 
 	/** Checks to see if the next token is the expected keyword.
 	 *
diff --git a/tests/pglabtests/pglabtests.pro b/tests/pglabtests/pglabtests.pro
index c19bbc9..004c52b 100644
--- a/tests/pglabtests/pglabtests.pro
+++ b/tests/pglabtests/pglabtests.pro
@@ -15,7 +15,7 @@ error( "Couldn't find the common.pri file!" )
 }
 
 
-HEADERS +=    
+HEADERS +=     
 
 SOURCES +=     main.cpp \
     tst_ExplainJsonParser.cpp \
@@ -28,7 +28,8 @@ SOURCES +=     main.cpp \
     tst_CodeBuilder.cpp \
     tst_NameManglingRules.cpp \
     tst_TypeMappings.cpp \
-    tst_Range.cpp
+    tst_Range.cpp \
+    tst_SqlParser.cpp
 
 win32:CONFIG(release, debug|release): LIBS += -L$$OUT_PWD/../../core/release/ -lcore
 else:win32:CONFIG(debug, debug|release): LIBS += -L$$OUT_PWD/../../core/debug/ -lcore
diff --git a/tests/pglabtests/tst_SqlParser.cpp b/tests/pglabtests/tst_SqlParser.cpp
new file mode 100644
index 0000000..9ce07df
--- /dev/null
+++ b/tests/pglabtests/tst_SqlParser.cpp
@@ -0,0 +1,30 @@
+#include <gtest/gtest.h>
+#include <gmock/gmock-matchers.h>
+#include "SqlLexer.h"
+#include "SqlParser.h"
+#include "SqlAstSelect.h"
+#include "PrintTo_Qt.h"
+
+using namespace testing;
+
+
+TEST(SqlParser, emptyFile)
+{
+	QString input;
+	SqlLexer lexer(input, LexerState::Null);
+	SqlParser parser(lexer);
+	auto res = parser.parse();
+
+	ASSERT_TRUE(res == nullptr);
+}
+
+TEST(SqlParser, select)
+{
+	QString input("SELECT");
+	SqlLexer lexer(input, LexerState::Null);
+	SqlParser parser(lexer);
+	auto res = parser.parse();
+
+	ASSERT_TRUE(res != nullptr);
+	ASSERT_EQ(typeid(*res), typeid(SqlAst::Select));
+}