From cb943a2179cd8e33983eb086e05def3e3e60bc28 Mon Sep 17 00:00:00 2001
From: Timothy Flynn <trflynn89@pm.me>
Date: Fri, 23 Apr 2021 13:37:47 -0400
Subject: [PATCH] LibSQL: Parse CREATE TABLE statements with a nested SELECT
 statement

---
 Userland/Libraries/LibSQL/AST.h                  | 16 ++++++++++++++++
 Userland/Libraries/LibSQL/Parser.cpp             |  5 ++++-
 .../LibSQL/Tests/TestSqlStatementParser.cpp      | 13 +++++++++++++
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/Userland/Libraries/LibSQL/AST.h b/Userland/Libraries/LibSQL/AST.h
index 96f0e970dc..fe8ff4d443 100644
--- a/Userland/Libraries/LibSQL/AST.h
+++ b/Userland/Libraries/LibSQL/AST.h
@@ -664,6 +664,15 @@ class ErrorStatement final : public Statement {
 
 class CreateTable : public Statement {
 public:
+    CreateTable(String schema_name, String table_name, RefPtr<Select> select_statement, bool is_temporary, bool is_error_if_table_exists)
+        : m_schema_name(move(schema_name))
+        , m_table_name(move(table_name))
+        , m_select_statement(move(select_statement))
+        , m_is_temporary(is_temporary)
+        , m_is_error_if_table_exists(is_error_if_table_exists)
+    {
+    }
+
     CreateTable(String schema_name, String table_name, NonnullRefPtrVector<ColumnDefinition> columns, bool is_temporary, bool is_error_if_table_exists)
         : m_schema_name(move(schema_name))
         , m_table_name(move(table_name))
@@ -675,13 +684,20 @@ public:
 
     const String& schema_name() const { return m_schema_name; }
     const String& table_name() const { return m_table_name; }
+
+    bool has_selection() const { return !m_select_statement.is_null(); }
+    const RefPtr<Select>& select_statement() const { return m_select_statement; }
+
+    bool has_columns() const { return !m_columns.is_empty(); }
     const NonnullRefPtrVector<ColumnDefinition> columns() const { return m_columns; }
+
     bool is_temporary() const { return m_is_temporary; }
     bool is_error_if_table_exists() const { return m_is_error_if_table_exists; }
 
 private:
     String m_schema_name;
     String m_table_name;
+    RefPtr<Select> m_select_statement;
     NonnullRefPtrVector<ColumnDefinition> m_columns;
     bool m_is_temporary;
     bool m_is_error_if_table_exists;
diff --git a/Userland/Libraries/LibSQL/Parser.cpp b/Userland/Libraries/LibSQL/Parser.cpp
index 8775c2d3b3..d1a7afda43 100644
--- a/Userland/Libraries/LibSQL/Parser.cpp
+++ b/Userland/Libraries/LibSQL/Parser.cpp
@@ -81,7 +81,10 @@ NonnullRefPtr<CreateTable> Parser::parse_create_table_statement()
     String table_name;
     parse_schema_and_table_name(schema_name, table_name);
 
-    // FIXME: Parse "AS select-stmt".
+    if (consume_if(TokenType::As)) {
+        auto select_statement = parse_select_statement({});
+        return create_ast_node<CreateTable>(move(schema_name), move(table_name), move(select_statement), is_temporary, is_error_if_table_exists);
+    }
 
     NonnullRefPtrVector<ColumnDefinition> column_definitions;
     parse_comma_separated_list(true, [&]() { column_definitions.append(parse_column_definition()); });
diff --git a/Userland/Libraries/LibSQL/Tests/TestSqlStatementParser.cpp b/Userland/Libraries/LibSQL/Tests/TestSqlStatementParser.cpp
index 7de8e45ed2..06b4b5f82d 100644
--- a/Userland/Libraries/LibSQL/Tests/TestSqlStatementParser.cpp
+++ b/Userland/Libraries/LibSQL/Tests/TestSqlStatementParser.cpp
@@ -45,6 +45,8 @@ TEST_CASE(create_table)
     EXPECT(parse("CREATE TABLE test ( column1 )").is_error());
     EXPECT(parse("CREATE TABLE IF test ( column1 );").is_error());
     EXPECT(parse("CREATE TABLE IF NOT test ( column1 );").is_error());
+    EXPECT(parse("CREATE TABLE AS;").is_error());
+    EXPECT(parse("CREATE TABLE AS SELECT;").is_error());
     EXPECT(parse("CREATE TABLE test ( column1 varchar()").is_error());
     EXPECT(parse("CREATE TABLE test ( column1 varchar(abc)").is_error());
     EXPECT(parse("CREATE TABLE test ( column1 varchar(123 )").is_error());
@@ -55,6 +57,8 @@ TEST_CASE(create_table)
     EXPECT(parse("CREATE TABLE test ( column1 varchar(0x) )").is_error());
     EXPECT(parse("CREATE TABLE test ( column1 varchar(0xzzz) )").is_error());
     EXPECT(parse("WITH table AS () CREATE TABLE test ( column1 );").is_error());
+    EXPECT(parse("CREATE TABLE test ( column1 int ) AS SELECT * FROM table;").is_error());
+    EXPECT(parse("CREATE TABLE test AS SELECT * FROM table ( column1 int ) ;").is_error());
 
     struct Column {
         StringView name;
@@ -75,6 +79,13 @@ TEST_CASE(create_table)
         EXPECT_EQ(table.is_temporary(), expected_is_temporary);
         EXPECT_EQ(table.is_error_if_table_exists(), expected_is_error_if_table_exists);
 
+        bool expect_select_statement = expected_columns.is_empty();
+        EXPECT_EQ(table.has_selection(), expect_select_statement);
+        EXPECT_EQ(table.has_columns(), !expect_select_statement);
+
+        const auto& select_statement = table.select_statement();
+        EXPECT_EQ(select_statement.is_null(), !expect_select_statement);
+
         const auto& columns = table.columns();
         EXPECT_EQ(columns.size(), expected_columns.size());
 
@@ -103,6 +114,8 @@ TEST_CASE(create_table)
     validate("CREATE TEMPORARY TABLE test ( column1 );", {}, "test", { { "column1", "BLOB" } }, true, true);
     validate("CREATE TABLE IF NOT EXISTS test ( column1 );", {}, "test", { { "column1", "BLOB" } }, false, false);
 
+    validate("CREATE TABLE test AS SELECT * FROM table;", {}, "test", {});
+
     validate("CREATE TABLE test ( column1 int );", {}, "test", { { "column1", "int" } });
     validate("CREATE TABLE test ( column1 varchar );", {}, "test", { { "column1", "varchar" } });
     validate("CREATE TABLE test ( column1 varchar(255) );", {}, "test", { { "column1", "varchar", { 255 } } });