blob: e3c26e7e4173e7df024fb3fea650644fcfc47c45 [file] [log] [blame]
#ifndef INCLUDE_INJA_PARSER_HPP_
#define INCLUDE_INJA_PARSER_HPP_
#include <limits>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#include "config.hpp"
#include "exceptions.hpp"
#include "function_storage.hpp"
#include "lexer.hpp"
#include "node.hpp"
#include "template.hpp"
#include "token.hpp"
#include "utils.hpp"
namespace inja {
/*!
* \brief Class for parsing an inja Template.
*/
class Parser {
const ParserConfig &config;
Lexer lexer;
TemplateStorage &template_storage;
const FunctionStorage &function_storage;
Token tok, peek_tok;
bool have_peek_tok {false};
size_t current_paren_level {0};
size_t current_bracket_level {0};
size_t current_brace_level {0};
std::string_view literal_start;
BlockNode *current_block {nullptr};
ExpressionListNode *current_expression_list {nullptr};
std::stack<std::pair<FunctionNode*, size_t>> function_stack;
std::vector<std::shared_ptr<ExpressionNode>> arguments;
std::stack<std::shared_ptr<FunctionNode>> operator_stack;
std::stack<IfStatementNode*> if_statement_stack;
std::stack<ForStatementNode*> for_statement_stack;
std::stack<BlockStatementNode*> block_statement_stack;
inline void throw_parser_error(const std::string &message) const {
INJA_THROW(ParserError(message, lexer.current_position()));
}
inline void get_next_token() {
if (have_peek_tok) {
tok = peek_tok;
have_peek_tok = false;
} else {
tok = lexer.scan();
}
}
inline void get_peek_token() {
if (!have_peek_tok) {
peek_tok = lexer.scan();
have_peek_tok = true;
}
}
inline void add_literal(const char* content_ptr) {
std::string_view data_text(literal_start.data(), tok.text.data() - literal_start.data() + tok.text.size());
arguments.emplace_back(std::make_shared<LiteralNode>(json::parse(data_text), data_text.data() - content_ptr));
}
inline void add_operator() {
auto function = operator_stack.top();
operator_stack.pop();
for (int i = 0; i < function->number_args; ++i) {
function->arguments.insert(function->arguments.begin(), arguments.back());
arguments.pop_back();
}
arguments.emplace_back(function);
}
void add_to_template_storage(std::string_view path, std::string& template_name) {
if (template_storage.find(template_name) != template_storage.end()) {
return;
}
std::string original_path = static_cast<std::string>(path);
std::string original_name = template_name;
if (config.search_included_templates_in_files) {
// Build the relative path
template_name = original_path + original_name;
if (template_name.compare(0, 2, "./") == 0) {
template_name.erase(0, 2);
}
if (template_storage.find(template_name) == template_storage.end()) {
// Load file
std::ifstream file;
file.open(template_name);
if (!file.fail()) {
std::string text((std::istreambuf_iterator<char>(file)), std::istreambuf_iterator<char>());
auto include_template = Template(text);
template_storage.emplace(template_name, include_template);
parse_into_template(template_storage[template_name], template_name);
return;
} else if (!config.include_callback) {
INJA_THROW(FileError("failed accessing file at '" + template_name + "'"));
}
}
}
// Try include callback
if (config.include_callback) {
auto include_template = config.include_callback(original_path, original_name);
template_storage.emplace(template_name, include_template);
}
}
std::string parse_filename(const Token& tok) const {
if (tok.kind != Token::Kind::String) {
throw_parser_error("expected string, got '" + tok.describe() + "'");
}
if (tok.text.length() < 2) {
throw_parser_error("expected filename, got '" + static_cast<std::string>(tok.text) + "'");
}
// Remove first and last character ""
return std::string {tok.text.substr(1, tok.text.length() - 2)};
}
bool parse_expression(Template &tmpl, Token::Kind closing) {
while (tok.kind != closing && tok.kind != Token::Kind::Eof) {
// Literals
switch (tok.kind) {
case Token::Kind::String: {
if (current_brace_level == 0 && current_bracket_level == 0) {
literal_start = tok.text;
add_literal(tmpl.content.c_str());
}
} break;
case Token::Kind::Number: {
if (current_brace_level == 0 && current_bracket_level == 0) {
literal_start = tok.text;
add_literal(tmpl.content.c_str());
}
} break;
case Token::Kind::LeftBracket: {
if (current_brace_level == 0 && current_bracket_level == 0) {
literal_start = tok.text;
}
current_bracket_level += 1;
} break;
case Token::Kind::LeftBrace: {
if (current_brace_level == 0 && current_bracket_level == 0) {
literal_start = tok.text;
}
current_brace_level += 1;
} break;
case Token::Kind::RightBracket: {
if (current_bracket_level == 0) {
throw_parser_error("unexpected ']'");
}
current_bracket_level -= 1;
if (current_brace_level == 0 && current_bracket_level == 0) {
add_literal(tmpl.content.c_str());
}
} break;
case Token::Kind::RightBrace: {
if (current_brace_level == 0) {
throw_parser_error("unexpected '}'");
}
current_brace_level -= 1;
if (current_brace_level == 0 && current_bracket_level == 0) {
add_literal(tmpl.content.c_str());
}
} break;
case Token::Kind::Id: {
get_peek_token();
// Data Literal
if (tok.text == static_cast<decltype(tok.text)>("true") || tok.text == static_cast<decltype(tok.text)>("false") || tok.text == static_cast<decltype(tok.text)>("null")) {
if (current_brace_level == 0 && current_bracket_level == 0) {
literal_start = tok.text;
add_literal(tmpl.content.c_str());
}
// Operator
} else if (tok.text == "and" || tok.text == "or" || tok.text == "in" || tok.text == "not") {
goto parse_operator;
// Functions
} else if (peek_tok.kind == Token::Kind::LeftParen) {
operator_stack.emplace(std::make_shared<FunctionNode>(static_cast<std::string>(tok.text), tok.text.data() - tmpl.content.c_str()));
function_stack.emplace(operator_stack.top().get(), current_paren_level);
// Variables
} else {
arguments.emplace_back(std::make_shared<DataNode>(static_cast<std::string>(tok.text), tok.text.data() - tmpl.content.c_str()));
}
// Operators
} break;
case Token::Kind::Equal:
case Token::Kind::NotEqual:
case Token::Kind::GreaterThan:
case Token::Kind::GreaterEqual:
case Token::Kind::LessThan:
case Token::Kind::LessEqual:
case Token::Kind::Plus:
case Token::Kind::Minus:
case Token::Kind::Times:
case Token::Kind::Slash:
case Token::Kind::Power:
case Token::Kind::Percent:
case Token::Kind::Dot: {
parse_operator:
FunctionStorage::Operation operation;
switch (tok.kind) {
case Token::Kind::Id: {
if (tok.text == "and") {
operation = FunctionStorage::Operation::And;
} else if (tok.text == "or") {
operation = FunctionStorage::Operation::Or;
} else if (tok.text == "in") {
operation = FunctionStorage::Operation::In;
} else if (tok.text == "not") {
operation = FunctionStorage::Operation::Not;
} else {
throw_parser_error("unknown operator in parser.");
}
} break;
case Token::Kind::Equal: {
operation = FunctionStorage::Operation::Equal;
} break;
case Token::Kind::NotEqual: {
operation = FunctionStorage::Operation::NotEqual;
} break;
case Token::Kind::GreaterThan: {
operation = FunctionStorage::Operation::Greater;
} break;
case Token::Kind::GreaterEqual: {
operation = FunctionStorage::Operation::GreaterEqual;
} break;
case Token::Kind::LessThan: {
operation = FunctionStorage::Operation::Less;
} break;
case Token::Kind::LessEqual: {
operation = FunctionStorage::Operation::LessEqual;
} break;
case Token::Kind::Plus: {
operation = FunctionStorage::Operation::Add;
} break;
case Token::Kind::Minus: {
operation = FunctionStorage::Operation::Subtract;
} break;
case Token::Kind::Times: {
operation = FunctionStorage::Operation::Multiplication;
} break;
case Token::Kind::Slash: {
operation = FunctionStorage::Operation::Division;
} break;
case Token::Kind::Power: {
operation = FunctionStorage::Operation::Power;
} break;
case Token::Kind::Percent: {
operation = FunctionStorage::Operation::Modulo;
} break;
case Token::Kind::Dot: {
operation = FunctionStorage::Operation::AtId;
} break;
default: {
throw_parser_error("unknown operator in parser.");
}
}
auto function_node = std::make_shared<FunctionNode>(operation, tok.text.data() - tmpl.content.c_str());
while (!operator_stack.empty() && ((operator_stack.top()->precedence > function_node->precedence) || (operator_stack.top()->precedence == function_node->precedence && function_node->associativity == FunctionNode::Associativity::Left)) && (operator_stack.top()->operation != FunctionStorage::Operation::ParenLeft)) {
add_operator();
}
operator_stack.emplace(function_node);
} break;
case Token::Kind::Comma: {
if (current_brace_level == 0 && current_bracket_level == 0) {
if (function_stack.empty()) {
throw_parser_error("unexpected ','");
}
function_stack.top().first->number_args += 1;
}
} break;
case Token::Kind::Colon: {
if (current_brace_level == 0 && current_bracket_level == 0) {
throw_parser_error("unexpected ':'");
}
} break;
case Token::Kind::LeftParen: {
current_paren_level += 1;
operator_stack.emplace(std::make_shared<FunctionNode>(FunctionStorage::Operation::ParenLeft, tok.text.data() - tmpl.content.c_str()));
get_peek_token();
if (peek_tok.kind == Token::Kind::RightParen) {
if (!function_stack.empty() && function_stack.top().second == current_paren_level - 1) {
function_stack.top().first->number_args = 0;
}
}
} break;
case Token::Kind::RightParen: {
current_paren_level -= 1;
while (!operator_stack.empty() && operator_stack.top()->operation != FunctionStorage::Operation::ParenLeft) {
add_operator();
}
if (!operator_stack.empty() && operator_stack.top()->operation == FunctionStorage::Operation::ParenLeft) {
operator_stack.pop();
}
if (!function_stack.empty() && function_stack.top().second == current_paren_level) {
auto func = function_stack.top().first;
auto function_data = function_storage.find_function(func->name, func->number_args);
if (function_data.operation == FunctionStorage::Operation::None) {
throw_parser_error("unknown function " + func->name);
}
func->operation = function_data.operation;
if (function_data.operation == FunctionStorage::Operation::Callback) {
func->callback = function_data.callback;
}
if (operator_stack.empty()) {
throw_parser_error("internal error at function " + func->name);
}
add_operator();
function_stack.pop();
}
}
default:
break;
}
get_next_token();
}
while (!operator_stack.empty()) {
add_operator();
}
if (arguments.size() == 1) {
current_expression_list->root = arguments[0];
arguments = {};
} else if (arguments.size() > 1) {
throw_parser_error("malformed expression");
}
return true;
}
bool parse_statement(Template &tmpl, Token::Kind closing, std::string_view path) {
if (tok.kind != Token::Kind::Id) {
return false;
}
if (tok.text == static_cast<decltype(tok.text)>("if")) {
get_next_token();
auto if_statement_node = std::make_shared<IfStatementNode>(current_block, tok.text.data() - tmpl.content.c_str());
current_block->nodes.emplace_back(if_statement_node);
if_statement_stack.emplace(if_statement_node.get());
current_block = &if_statement_node->true_statement;
current_expression_list = &if_statement_node->condition;
if (!parse_expression(tmpl, closing)) {
return false;
}
} else if (tok.text == static_cast<decltype(tok.text)>("else")) {
if (if_statement_stack.empty()) {
throw_parser_error("else without matching if");
}
auto &if_statement_data = if_statement_stack.top();
get_next_token();
if_statement_data->has_false_statement = true;
current_block = &if_statement_data->false_statement;
// Chained else if
if (tok.kind == Token::Kind::Id && tok.text == static_cast<decltype(tok.text)>("if")) {
get_next_token();
auto if_statement_node = std::make_shared<IfStatementNode>(true, current_block, tok.text.data() - tmpl.content.c_str());
current_block->nodes.emplace_back(if_statement_node);
if_statement_stack.emplace(if_statement_node.get());
current_block = &if_statement_node->true_statement;
current_expression_list = &if_statement_node->condition;
if (!parse_expression(tmpl, closing)) {
return false;
}
}
} else if (tok.text == static_cast<decltype(tok.text)>("endif")) {
if (if_statement_stack.empty()) {
throw_parser_error("endif without matching if");
}
// Nested if statements
while (if_statement_stack.top()->is_nested) {
if_statement_stack.pop();
}
auto &if_statement_data = if_statement_stack.top();
get_next_token();
current_block = if_statement_data->parent;
if_statement_stack.pop();
} else if (tok.text == static_cast<decltype(tok.text)>("block")) {
get_next_token();
if (tok.kind != Token::Kind::Id) {
throw_parser_error("expected block name, got '" + tok.describe() + "'");
}
const std::string block_name = static_cast<std::string>(tok.text);
auto block_statement_node = std::make_shared<BlockStatementNode>(current_block, block_name, tok.text.data() - tmpl.content.c_str());
current_block->nodes.emplace_back(block_statement_node);
block_statement_stack.emplace(block_statement_node.get());
current_block = &block_statement_node->block;
auto success = tmpl.block_storage.emplace(block_name, block_statement_node);
if (!success.second) {
throw_parser_error("block with the name '" + block_name + "' does already exist");
}
get_next_token();
} else if (tok.text == static_cast<decltype(tok.text)>("endblock")) {
if (block_statement_stack.empty()) {
throw_parser_error("endblock without matching block");
}
auto &block_statement_data = block_statement_stack.top();
get_next_token();
current_block = block_statement_data->parent;
block_statement_stack.pop();
} else if (tok.text == static_cast<decltype(tok.text)>("for")) {
get_next_token();
// options: for a in arr; for a, b in obj
if (tok.kind != Token::Kind::Id) {
throw_parser_error("expected id, got '" + tok.describe() + "'");
}
Token value_token = tok;
get_next_token();
// Object type
std::shared_ptr<ForStatementNode> for_statement_node;
if (tok.kind == Token::Kind::Comma) {
get_next_token();
if (tok.kind != Token::Kind::Id) {
throw_parser_error("expected id, got '" + tok.describe() + "'");
}
Token key_token = std::move(value_token);
value_token = tok;
get_next_token();
for_statement_node = std::make_shared<ForObjectStatementNode>(static_cast<std::string>(key_token.text), static_cast<std::string>(value_token.text), current_block, tok.text.data() - tmpl.content.c_str());
// Array type
} else {
for_statement_node = std::make_shared<ForArrayStatementNode>(static_cast<std::string>(value_token.text), current_block, tok.text.data() - tmpl.content.c_str());
}
current_block->nodes.emplace_back(for_statement_node);
for_statement_stack.emplace(for_statement_node.get());
current_block = &for_statement_node->body;
current_expression_list = &for_statement_node->condition;
if (tok.kind != Token::Kind::Id || tok.text != static_cast<decltype(tok.text)>("in")) {
throw_parser_error("expected 'in', got '" + tok.describe() + "'");
}
get_next_token();
if (!parse_expression(tmpl, closing)) {
return false;
}
} else if (tok.text == static_cast<decltype(tok.text)>("endfor")) {
if (for_statement_stack.empty()) {
throw_parser_error("endfor without matching for");
}
auto &for_statement_data = for_statement_stack.top();
get_next_token();
current_block = for_statement_data->parent;
for_statement_stack.pop();
} else if (tok.text == static_cast<decltype(tok.text)>("include")) {
get_next_token();
std::string template_name = parse_filename(tok);
add_to_template_storage(path, template_name);
current_block->nodes.emplace_back(std::make_shared<IncludeStatementNode>(template_name, tok.text.data() - tmpl.content.c_str()));
get_next_token();
} else if (tok.text == static_cast<decltype(tok.text)>("extends")) {
get_next_token();
std::string template_name = parse_filename(tok);
add_to_template_storage(path, template_name);
current_block->nodes.emplace_back(std::make_shared<ExtendsStatementNode>(template_name, tok.text.data() - tmpl.content.c_str()));
get_next_token();
} else if (tok.text == static_cast<decltype(tok.text)>("set")) {
get_next_token();
if (tok.kind != Token::Kind::Id) {
throw_parser_error("expected variable name, got '" + tok.describe() + "'");
}
std::string key = static_cast<std::string>(tok.text);
get_next_token();
auto set_statement_node = std::make_shared<SetStatementNode>(key, tok.text.data() - tmpl.content.c_str());
current_block->nodes.emplace_back(set_statement_node);
current_expression_list = &set_statement_node->expression;
if (tok.text != static_cast<decltype(tok.text)>("=")) {
throw_parser_error("expected '=', got '" + tok.describe() + "'");
}
get_next_token();
if (!parse_expression(tmpl, closing)) {
return false;
}
} else {
return false;
}
return true;
}
void parse_into(Template &tmpl, std::string_view path) {
lexer.start(tmpl.content);
current_block = &tmpl.root;
for (;;) {
get_next_token();
switch (tok.kind) {
case Token::Kind::Eof: {
if (!if_statement_stack.empty()) {
throw_parser_error("unmatched if");
}
if (!for_statement_stack.empty()) {
throw_parser_error("unmatched for");
}
} return;
case Token::Kind::Text: {
current_block->nodes.emplace_back(std::make_shared<TextNode>(tok.text.data() - tmpl.content.c_str(), tok.text.size()));
} break;
case Token::Kind::StatementOpen: {
get_next_token();
if (!parse_statement(tmpl, Token::Kind::StatementClose, path)) {
throw_parser_error("expected statement, got '" + tok.describe() + "'");
}
if (tok.kind != Token::Kind::StatementClose) {
throw_parser_error("expected statement close, got '" + tok.describe() + "'");
}
} break;
case Token::Kind::LineStatementOpen: {
get_next_token();
if (!parse_statement(tmpl, Token::Kind::LineStatementClose, path)) {
throw_parser_error("expected statement, got '" + tok.describe() + "'");
}
if (tok.kind != Token::Kind::LineStatementClose && tok.kind != Token::Kind::Eof) {
throw_parser_error("expected line statement close, got '" + tok.describe() + "'");
}
} break;
case Token::Kind::ExpressionOpen: {
get_next_token();
auto expression_list_node = std::make_shared<ExpressionListNode>(tok.text.data() - tmpl.content.c_str());
current_block->nodes.emplace_back(expression_list_node);
current_expression_list = expression_list_node.get();
if (!parse_expression(tmpl, Token::Kind::ExpressionClose)) {
throw_parser_error("expected expression, got '" + tok.describe() + "'");
}
if (tok.kind != Token::Kind::ExpressionClose) {
throw_parser_error("expected expression close, got '" + tok.describe() + "'");
}
} break;
case Token::Kind::CommentOpen: {
get_next_token();
if (tok.kind != Token::Kind::CommentClose) {
throw_parser_error("expected comment close, got '" + tok.describe() + "'");
}
} break;
default: {
throw_parser_error("unexpected token '" + tok.describe() + "'");
} break;
}
}
}
public:
explicit Parser(const ParserConfig &parser_config, const LexerConfig &lexer_config,
TemplateStorage &template_storage, const FunctionStorage &function_storage)
: config(parser_config), lexer(lexer_config), template_storage(template_storage), function_storage(function_storage) { }
Template parse(std::string_view input, std::string_view path) {
auto result = Template(static_cast<std::string>(input));
parse_into(result, path);
return result;
}
Template parse(std::string_view input) {
return parse(input, "./");
}
void parse_into_template(Template& tmpl, std::string_view filename) {
std::string_view path = filename.substr(0, filename.find_last_of("/\\") + 1);
// StringRef path = sys::path::parent_path(filename);
auto sub_parser = Parser(config, lexer.get_config(), template_storage, function_storage);
sub_parser.parse_into(tmpl, path);
}
std::string load_file(const std::string& filename) {
std::ifstream file;
file.open(filename);
if (file.fail()) {
INJA_THROW(FileError("failed accessing file at '" + filename + "'"));
}
std::string text((std::istreambuf_iterator<char>(file)), std::istreambuf_iterator<char>());
return text;
}
};
} // namespace inja
#endif // INCLUDE_INJA_PARSER_HPP_