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#include "sass.hpp" #include "parser.hpp" #include "file.hpp" #include "inspect.hpp" #include "constants.hpp" #include "util.hpp" #include "prelexer.hpp" #include "color_maps.hpp" #include "sass/functions.h" #include "error_handling.hpp" // Notes about delayed: some ast nodes can have delayed evaluation so // they can preserve their original semantics if needed. This is most // prominently exhibited by the division operation, since it is not // only a valid operation, but also a valid css statement (i.e. for // fonts, as in `16px/24px`). When parsing lists and expression we // unwrap single items from lists and other operations. A nested list // must not be delayed, only the items of the first level sometimes // are delayed (as with argument lists). To achieve this we need to // pass status to the list parser, so this can be set correctly. // Another case with delayed values are colors. In compressed mode // only processed values get compressed (other are left as written). #include <cstdlib> #include <iostream> #include <vector> #include <typeinfo> namespace Sass { using namespace Constants; using namespace Prelexer; Parser Parser::from_c_str(const char* beg, Context& ctx, Backtraces traces, ParserState pstate, const char* source) { pstate.offset.column = 0; pstate.offset.line = 0; Parser p(ctx, pstate, traces); p.source = source ? source : beg; p.position = beg ? beg : p.source; p.end = p.position + strlen(p.position); Block_Obj root = SASS_MEMORY_NEW(Block, pstate); p.block_stack.push_back(root); root->is_root(true); return p; } Parser Parser::from_c_str(const char* beg, const char* end, Context& ctx, Backtraces traces, ParserState pstate, const char* source) { pstate.offset.column = 0; pstate.offset.line = 0; Parser p(ctx, pstate, traces); p.source = source ? source : beg; p.position = beg ? beg : p.source; p.end = end ? end : p.position + strlen(p.position); Block_Obj root = SASS_MEMORY_NEW(Block, pstate); p.block_stack.push_back(root); root->is_root(true); return p; } void Parser::advanceToNextToken() { lex < css_comments >(false); // advance to position pstate += pstate.offset; pstate.offset.column = 0; pstate.offset.line = 0; } Selector_List_Obj Parser::parse_selector(const char* beg, Context& ctx, Backtraces traces, ParserState pstate, const char* source) { Parser p = Parser::from_c_str(beg, ctx, traces, pstate, source); // ToDo: ruby sass errors on parent references // ToDo: remap the source-map entries somehow return p.parse_selector_list(false); } bool Parser::peek_newline(const char* start) { return peek_linefeed(start ? start : position) && ! peek_css<exactly<'{'>>(start); } Parser Parser::from_token(Token t, Context& ctx, Backtraces traces, ParserState pstate, const char* source) { Parser p(ctx, pstate, traces); p.source = source ? source : t.begin; p.position = t.begin ? t.begin : p.source; p.end = t.end ? t.end : p.position + strlen(p.position); Block_Obj root = SASS_MEMORY_NEW(Block, pstate); p.block_stack.push_back(root); root->is_root(true); return p; } /* main entry point to parse root block */ Block_Obj Parser::parse() { // consume unicode BOM read_bom(); // scan the input to find invalid utf8 sequences const char* it = utf8::find_invalid(position, end); // report invalid utf8 if (it != end) { pstate += Offset::init(position, it); traces.push_back(Backtrace(pstate)); throw Exception::InvalidSass(pstate, traces, "Invalid UTF-8 sequence"); } // create a block AST node to hold children Block_Obj root = SASS_MEMORY_NEW(Block, pstate, 0, true); // check seems a bit esoteric but works if (ctx.resources.size() == 1) { // apply headers only on very first include ctx.apply_custom_headers(root, path, pstate); } // parse children nodes block_stack.push_back(root); parse_block_nodes(true); block_stack.pop_back(); // update final position root->update_pstate(pstate); if (position != end) { css_error("Invalid CSS", " after ", ": expected selector or at-rule, was "); } return root; } // convenience function for block parsing // will create a new block ad-hoc for you // this is the base block parsing function Block_Obj Parser::parse_css_block(bool is_root) { // parse comments before block // lex < optional_css_comments >(); // lex mandatory opener or error out if (!lex_css < exactly<'{'> >()) { css_error("Invalid CSS", " after ", ": expected \"{\", was "); } // create new block and push to the selector stack Block_Obj block = SASS_MEMORY_NEW(Block, pstate, 0, is_root); block_stack.push_back(block); if (!parse_block_nodes(is_root)) css_error("Invalid CSS", " after ", ": expected \"}\", was "); if (!lex_css < exactly<'}'> >()) { css_error("Invalid CSS", " after ", ": expected \"}\", was "); } // update for end position // this seems to be done somewhere else // but that fixed selector schema issue // block->update_pstate(pstate); // parse comments after block // lex < optional_css_comments >(); block_stack.pop_back(); return block; } // convenience function for block parsing // will create a new block ad-hoc for you // also updates the `in_at_root` flag Block_Obj Parser::parse_block(bool is_root) { return parse_css_block(is_root); } // the main block parsing function // parses stuff between `{` and `}` bool Parser::parse_block_nodes(bool is_root) { // loop until end of string while (position < end) { // we should be able to refactor this parse_block_comments(); lex < css_whitespace >(); if (lex < exactly<';'> >()) continue; if (peek < end_of_file >()) return true; if (peek < exactly<'}'> >()) return true; if (parse_block_node(is_root)) continue; parse_block_comments(); if (lex_css < exactly<';'> >()) continue; if (peek_css < end_of_file >()) return true; if (peek_css < exactly<'}'> >()) return true; // illegal sass return false; } // return success return true; } // parser for a single node in a block // semicolons must be lexed beforehand bool Parser::parse_block_node(bool is_root) { Block_Obj block = block_stack.back(); parse_block_comments(); // throw away white-space // includes line comments lex < css_whitespace >(); Lookahead lookahead_result; // also parse block comments // first parse everything that is allowed in functions if (lex < variable >(true)) { block->append(parse_assignment()); } else if (lex < kwd_err >(true)) { block->append(parse_error()); } else if (lex < kwd_dbg >(true)) { block->append(parse_debug()); } else if (lex < kwd_warn >(true)) { block->append(parse_warning()); } else if (lex < kwd_if_directive >(true)) { block->append(parse_if_directive()); } else if (lex < kwd_for_directive >(true)) { block->append(parse_for_directive()); } else if (lex < kwd_each_directive >(true)) { block->append(parse_each_directive()); } else if (lex < kwd_while_directive >(true)) { block->append(parse_while_directive()); } else if (lex < kwd_return_directive >(true)) { block->append(parse_return_directive()); } // parse imports to process later else if (lex < kwd_import >(true)) { Scope parent = stack.empty() ? Scope::Rules : stack.back(); if (parent != Scope::Function && parent != Scope::Root && parent != Scope::Rules && parent != Scope::Media) { if (! peek_css< uri_prefix >(position)) { // this seems to go in ruby sass 3.4.20 error("Import directives may not be used within control directives or mixins.");