================ @@ -0,0 +1,785 @@ +//===-- Mustache.cpp ------------------------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "llvm/Support/Mustache.h" +#include "llvm/Support/Error.h" +#include "llvm/Support/raw_ostream.h" +#include <sstream> + +using namespace llvm; +using namespace llvm::json; +using namespace llvm::mustache; + +namespace { + +static bool isFalsey(const Value &V) { + return V.getAsNull() || (V.getAsBoolean() && !V.getAsBoolean().value()) || + (V.getAsArray() && V.getAsArray()->empty()) || + (V.getAsObject() && V.getAsObject()->empty()); +} + +static Accessor splitMustacheString(StringRef Str) { + // We split the mustache string into an accessor. + // For example: + // "a.b.c" would be split into {"a", "b", "c"} + // We make an exception for a single dot which + // refers to the current context. + Accessor Tokens; + if (Str == ".") { + Tokens.emplace_back(Str); + return Tokens; + } + while (!Str.empty()) { + StringRef Part; + std::tie(Part, Str) = Str.split("."); + Tokens.emplace_back(Part.trim()); + } + return Tokens; +} + +} // namespace + +namespace llvm { +namespace mustache { + +class Token { +public: + enum class Type { + Text, + Variable, + Partial, + SectionOpen, + SectionClose, + InvertSectionOpen, + UnescapeVariable, + Comment, + }; + + Token(std::string Str); + + Token(std::string RawBody, std::string TokenBody, char Identifier); + + StringRef getTokenBody() const { return TokenBody; }; + + StringRef getRawBody() const { return RawBody; }; + + void setTokenBody(std::string NewBody) { TokenBody = std::move(NewBody); }; + + Accessor getAccessor() const { return Accessor; }; + + Type getType() const { return TokenType; }; + + void setIndentation(size_t NewIndentation) { Indentation = NewIndentation; }; + + size_t getIndentation() const { return Indentation; }; + + static Type getTokenType(char Identifier); + +private: + Type TokenType; + // RawBody is the original string that was tokenized. + std::string RawBody; + // TokenBody is the original string with the identifier removed. + std::string TokenBody; + Accessor Accessor; + size_t Indentation; +}; + +class ASTNode { +public: + enum Type { + Root, + Text, + Partial, + Variable, + UnescapeVariable, + Section, + InvertSection, + }; + + ASTNode(llvm::BumpPtrAllocator &Alloc, llvm::StringMap<ASTNode *> &Partials, + llvm::StringMap<Lambda> &Lambdas, + llvm::StringMap<SectionLambda> &SectionLambdas, + llvm::DenseMap<char, std::string> &Escapes) + : Allocator(Alloc), Partials(Partials), Lambdas(Lambdas), + SectionLambdas(SectionLambdas), Escapes(Escapes), T(Type::Root), + ParentContext(nullptr) {}; + + ASTNode(llvm::StringRef Body, ASTNode *Parent, llvm::BumpPtrAllocator &Alloc, + llvm::StringMap<ASTNode *> &Partials, + llvm::StringMap<Lambda> &Lambdas, + llvm::StringMap<SectionLambda> &SectionLambdas, + llvm::DenseMap<char, std::string> &Escapes) + : Allocator(Alloc), Partials(Partials), Lambdas(Lambdas), + SectionLambdas(SectionLambdas), Escapes(Escapes), T(Type::Text), + Body(Body.str()), Parent(Parent), ParentContext(nullptr) {} + + // Constructor for Section/InvertSection/Variable/UnescapeVariable Nodes + ASTNode(Type T, Accessor Accessor, ASTNode *Parent, + llvm::BumpPtrAllocator &Alloc, llvm::StringMap<ASTNode *> &Partials, + llvm::StringMap<Lambda> &Lambdas, + llvm::StringMap<SectionLambda> &SectionLambdas, + llvm::DenseMap<char, std::string> &Escapes) + : Allocator(Alloc), Partials(Partials), Lambdas(Lambdas), + SectionLambdas(SectionLambdas), Escapes(Escapes), T(T), + Accessor(Accessor), Parent(Parent), ParentContext(nullptr) {} + + void addChild(ASTNode *Child) { Children.emplace_back(Child); }; + + void setRawBody(std::string NewBody) { RawBody = std::move(NewBody); }; + + void setIndentation(size_t NewIndentation) { Indentation = NewIndentation; }; + + void render(const llvm::json::Value &Data, llvm::raw_ostream &OS); + +private: + void renderLambdas(const llvm::json::Value &Contexts, llvm::raw_ostream &OS, + Lambda &L); + + void renderSectionLambdas(const llvm::json::Value &Contexts, + llvm::raw_ostream &OS, SectionLambda &L); + + void renderPartial(const llvm::json::Value &Contexts, llvm::raw_ostream &OS, + ASTNode *Partial); + + void renderChild(const llvm::json::Value &Context, llvm::raw_ostream &OS); + + const llvm::json::Value *findContext(); + + llvm::BumpPtrAllocator &Allocator; + StringMap<ASTNode *> &Partials; + StringMap<Lambda> &Lambdas; + StringMap<SectionLambda> &SectionLambdas; + DenseMap<char, std::string> &Escapes; + Type T; + size_t Indentation = 0; + std::string RawBody; + std::string Body; + ASTNode *Parent; + // TODO: switch implementation to SmallVector<T> + std::vector<ASTNode *> Children; + const Accessor Accessor; + const llvm::json::Value *ParentContext; +}; + +// syntax wrapper for arena allocator for ASTNodes + +auto CreateRootNode = + [](void *Node, llvm::BumpPtrAllocator &Alloc, + llvm::StringMap<ASTNode *> &Partials, llvm::StringMap<Lambda> &Lambdas, + llvm::StringMap<SectionLambda> &SectionLambdas, + llvm::DenseMap<char, std::string> &Escapes) -> ASTNode * { + return new (Node) ASTNode(Alloc, Partials, Lambdas, SectionLambdas, Escapes); +}; + +auto CreateNode = [](void *Node, ASTNode::Type T, Accessor A, ASTNode *Parent, + llvm::BumpPtrAllocator &Alloc, + llvm::StringMap<ASTNode *> &Partials, + llvm::StringMap<Lambda> &Lambdas, + llvm::StringMap<SectionLambda> &SectionLambdas, + llvm::DenseMap<char, std::string> &Escapes) -> ASTNode * { + return new (Node) + ASTNode(T, A, Parent, Alloc, Partials, Lambdas, SectionLambdas, Escapes); +}; + +auto CreateTextNode = + [](void *Node, StringRef Body, ASTNode *Parent, + llvm::BumpPtrAllocator &Alloc, llvm::StringMap<ASTNode *> &Partials, + llvm::StringMap<Lambda> &Lambdas, + llvm::StringMap<SectionLambda> &SectionLambdas, + llvm::DenseMap<char, std::string> &Escapes) -> ASTNode * { + return new (Node) + ASTNode(Body, Parent, Alloc, Partials, Lambdas, SectionLambdas, Escapes); +}; + +// Function to check if there is meaningful text behind. +// We determine if a token has meaningful text behind +// if the right of previous token contains anything that is +// not a newline. +// For example: +// "Stuff {{#Section}}" (returns true) +// vs +// "{{#Section}} \n" (returns false) +// We make an exception for when previous token is empty +// and the current token is the second token. +// For example: +// "{{#Section}}" +bool hasTextBehind(size_t Idx, const ArrayRef<Token> &Tokens) { + if (Idx == 0) + return true; + + int PrevIdx = Idx - 1; + if (Tokens[PrevIdx].getType() != Token::Type::Text) + return true; + + const Token &PrevToken = Tokens[PrevIdx]; + StringRef TokenBody = PrevToken.getRawBody().rtrim(" \t\v"); + return !TokenBody.ends_with("\n") && !(TokenBody.empty() && Idx == 1); +} + +// Function to check if there's no meaningful text ahead. +// We determine if a token has text ahead if the left of previous +// token does not start with a newline. +bool hasTextAhead(size_t Idx, const ArrayRef<Token> &Tokens) { + if (Idx >= Tokens.size() - 1) + return true; + + int NextIdx = Idx + 1; + if (Tokens[NextIdx].getType() != Token::Type::Text) + return true; + + const Token &NextToken = Tokens[NextIdx]; + StringRef TokenBody = NextToken.getRawBody().ltrim(" "); + return !TokenBody.starts_with("\r\n") && !TokenBody.starts_with("\n"); +} + +bool requiresCleanUp(Token::Type T) { + // We must clean up all the tokens that could contain child nodes. + return T == Token::Type::SectionOpen || T == Token::Type::InvertSectionOpen || + T == Token::Type::SectionClose || T == Token::Type::Comment || + T == Token::Type::Partial; +} + +// Adjust next token body if there is no text ahead. +// For example: +// The template string +// "{{! Comment }} \nLine 2" +// would be considered as no text ahead and should be rendered as +// " Line 2" +void stripTokenAhead(SmallVectorImpl<Token> &Tokens, size_t Idx) { + Token &NextToken = Tokens[Idx + 1]; + StringRef NextTokenBody = NextToken.getTokenBody(); + // cut off the leading newline which could be \n or \r\n + if (NextTokenBody.starts_with("\r\n")) + NextToken.setTokenBody(NextTokenBody.substr(2).str()); + else if (NextTokenBody.starts_with("\n")) + NextToken.setTokenBody(NextTokenBody.substr(1).str()); +} + +// Adjust previous token body if there no text behind. +// For example: +// The template string +// " \t{{#section}}A{{/section}}" +// would be considered as having no text ahead and would be render as +// "A" +// The exception for this is partial tag which requires us to +// keep track of the indentation once it's rendered. +void stripTokenBefore(SmallVectorImpl<Token> &Tokens, size_t Idx, + Token &CurrentToken, Token::Type CurrentType) { + Token &PrevToken = Tokens[Idx - 1]; + StringRef PrevTokenBody = PrevToken.getTokenBody(); + StringRef Unindented = PrevTokenBody.rtrim(" \t\v"); + size_t Indentation = PrevTokenBody.size() - Unindented.size(); + if (CurrentType != Token::Type::Partial) + PrevToken.setTokenBody(Unindented.str()); + CurrentToken.setIndentation(Indentation); +} + +// Simple tokenizer that splits the template into tokens. +// The mustache spec allows {{{ }}} to unescape variables, +// but we don't support that here. An unescape variable +// is represented only by {{& variable}}. +SmallVector<Token> tokenize(StringRef Template) { + SmallVector<Token> Tokens; + const StringRef Open("{{"); + const StringRef Close("}}"); ---------------- ilovepi wrote:
`StringRef` is already const. you don't need to mark it as such. https://github.com/llvm/llvm-project/pull/105893 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
