diff options
Diffstat (limited to 'vendor/github.com/antlr4-go/antlr/v4/parser.go')
| -rw-r--r-- | vendor/github.com/antlr4-go/antlr/v4/parser.go | 700 |
1 files changed, 700 insertions, 0 deletions
diff --git a/vendor/github.com/antlr4-go/antlr/v4/parser.go b/vendor/github.com/antlr4-go/antlr/v4/parser.go new file mode 100644 index 0000000..fb57ac1 --- /dev/null +++ b/vendor/github.com/antlr4-go/antlr/v4/parser.go @@ -0,0 +1,700 @@ +// Copyright (c) 2012-2022 The ANTLR Project. All rights reserved. +// Use of this file is governed by the BSD 3-clause license that +// can be found in the LICENSE.txt file in the project root. + +package antlr + +import ( + "fmt" + "strconv" +) + +type Parser interface { + Recognizer + + GetInterpreter() *ParserATNSimulator + + GetTokenStream() TokenStream + GetTokenFactory() TokenFactory + GetParserRuleContext() ParserRuleContext + SetParserRuleContext(ParserRuleContext) + Consume() Token + GetParseListeners() []ParseTreeListener + + GetErrorHandler() ErrorStrategy + SetErrorHandler(ErrorStrategy) + GetInputStream() IntStream + GetCurrentToken() Token + GetExpectedTokens() *IntervalSet + NotifyErrorListeners(string, Token, RecognitionException) + IsExpectedToken(int) bool + GetPrecedence() int + GetRuleInvocationStack(ParserRuleContext) []string +} + +type BaseParser struct { + *BaseRecognizer + + Interpreter *ParserATNSimulator + BuildParseTrees bool + + input TokenStream + errHandler ErrorStrategy + precedenceStack IntStack + ctx ParserRuleContext + + tracer *TraceListener + parseListeners []ParseTreeListener + _SyntaxErrors int +} + +// NewBaseParser contains all the parsing support code to embed in parsers. Essentially most of it is error +// recovery stuff. +// +//goland:noinspection GoUnusedExportedFunction +func NewBaseParser(input TokenStream) *BaseParser { + + p := new(BaseParser) + + p.BaseRecognizer = NewBaseRecognizer() + + // The input stream. + p.input = nil + + // The error handling strategy for the parser. The default value is a new + // instance of {@link DefaultErrorStrategy}. + p.errHandler = NewDefaultErrorStrategy() + p.precedenceStack = make([]int, 0) + p.precedenceStack.Push(0) + + // The ParserRuleContext object for the currently executing rule. + // p.is always non-nil during the parsing process. + p.ctx = nil + + // Specifies whether the parser should construct a parse tree during + // the parsing process. The default value is {@code true}. + p.BuildParseTrees = true + + // When setTrace(true) is called, a reference to the + // TraceListener is stored here, so it can be easily removed in a + // later call to setTrace(false). The listener itself is + // implemented as a parser listener so p.field is not directly used by + // other parser methods. + p.tracer = nil + + // The list of ParseTreeListener listeners registered to receive + // events during the parse. + p.parseListeners = nil + + // The number of syntax errors Reported during parsing. p.value is + // incremented each time NotifyErrorListeners is called. + p._SyntaxErrors = 0 + p.SetInputStream(input) + + return p +} + +// This field maps from the serialized ATN string to the deserialized [ATN] with +// bypass alternatives. +// +// [ATNDeserializationOptions.isGenerateRuleBypassTransitions] +// +//goland:noinspection GoUnusedGlobalVariable +var bypassAltsAtnCache = make(map[string]int) + +// reset the parser's state// +func (p *BaseParser) reset() { + if p.input != nil { + p.input.Seek(0) + } + p.errHandler.reset(p) + p.ctx = nil + p._SyntaxErrors = 0 + p.SetTrace(nil) + p.precedenceStack = make([]int, 0) + p.precedenceStack.Push(0) + if p.Interpreter != nil { + p.Interpreter.reset() + } +} + +func (p *BaseParser) GetErrorHandler() ErrorStrategy { + return p.errHandler +} + +func (p *BaseParser) SetErrorHandler(e ErrorStrategy) { + p.errHandler = e +} + +// Match current input symbol against {@code ttype}. If the symbol type +// Matches, {@link ANTLRErrorStrategy//ReportMatch} and {@link //consume} are +// called to complete the Match process. +// +// <p>If the symbol type does not Match, +// {@link ANTLRErrorStrategy//recoverInline} is called on the current error +// strategy to attempt recovery. If {@link //getBuildParseTree} is +// {@code true} and the token index of the symbol returned by +// {@link ANTLRErrorStrategy//recoverInline} is -1, the symbol is added to +// the parse tree by calling {@link ParserRuleContext//addErrorNode}.</p> +// +// @param ttype the token type to Match +// @return the Matched symbol +// @panics RecognitionException if the current input symbol did not Match +// {@code ttype} and the error strategy could not recover from the +// mismatched symbol + +func (p *BaseParser) Match(ttype int) Token { + + t := p.GetCurrentToken() + + if t.GetTokenType() == ttype { + p.errHandler.ReportMatch(p) + p.Consume() + } else { + t = p.errHandler.RecoverInline(p) + if p.HasError() { + return nil + } + if p.BuildParseTrees && t.GetTokenIndex() == -1 { + + // we must have conjured up a new token during single token + // insertion if it's not the current symbol + p.ctx.AddErrorNode(t) + } + } + + return t +} + +// Match current input symbol as a wildcard. If the symbol type Matches +// (i.e. has a value greater than 0), {@link ANTLRErrorStrategy//ReportMatch} +// and {@link //consume} are called to complete the Match process. +// +// <p>If the symbol type does not Match, +// {@link ANTLRErrorStrategy//recoverInline} is called on the current error +// strategy to attempt recovery. If {@link //getBuildParseTree} is +// {@code true} and the token index of the symbol returned by +// {@link ANTLRErrorStrategy//recoverInline} is -1, the symbol is added to +// the parse tree by calling {@link ParserRuleContext//addErrorNode}.</p> +// +// @return the Matched symbol +// @panics RecognitionException if the current input symbol did not Match +// a wildcard and the error strategy could not recover from the mismatched +// symbol + +func (p *BaseParser) MatchWildcard() Token { + t := p.GetCurrentToken() + if t.GetTokenType() > 0 { + p.errHandler.ReportMatch(p) + p.Consume() + } else { + t = p.errHandler.RecoverInline(p) + if p.BuildParseTrees && t.GetTokenIndex() == -1 { + // we must have conjured up a new token during single token + // insertion if it's not the current symbol + p.ctx.AddErrorNode(t) + } + } + return t +} + +func (p *BaseParser) GetParserRuleContext() ParserRuleContext { + return p.ctx +} + +func (p *BaseParser) SetParserRuleContext(v ParserRuleContext) { + p.ctx = v +} + +func (p *BaseParser) GetParseListeners() []ParseTreeListener { + if p.parseListeners == nil { + return make([]ParseTreeListener, 0) + } + return p.parseListeners +} + +// AddParseListener registers listener to receive events during the parsing process. +// +// To support output-preserving grammar transformations (including but not +// limited to left-recursion removal, automated left-factoring, and +// optimized code generation), calls to listener methods during the parse +// may differ substantially from calls made by +// [ParseTreeWalker.DEFAULT] used after the parse is complete. In +// particular, rule entry and exit events may occur in a different order +// during the parse than after the parser. In addition, calls to certain +// rule entry methods may be omitted. +// +// With the following specific exceptions, calls to listener events are +// deterministic, i.e. for identical input the calls to listener +// methods will be the same. +// +// - Alterations to the grammar used to generate code may change the +// behavior of the listener calls. +// - Alterations to the command line options passed to ANTLR 4 when +// generating the parser may change the behavior of the listener calls. +// - Changing the version of the ANTLR Tool used to generate the parser +// may change the behavior of the listener calls. +func (p *BaseParser) AddParseListener(listener ParseTreeListener) { + if listener == nil { + panic("listener") + } + if p.parseListeners == nil { + p.parseListeners = make([]ParseTreeListener, 0) + } + p.parseListeners = append(p.parseListeners, listener) +} + +// RemoveParseListener removes listener from the list of parse listeners. +// +// If listener is nil or has not been added as a parse +// listener, this func does nothing. +func (p *BaseParser) RemoveParseListener(listener ParseTreeListener) { + + if p.parseListeners != nil { + + idx := -1 + for i, v := range p.parseListeners { + if v == listener { + idx = i + break + } + } + + if idx == -1 { + return + } + + // remove the listener from the slice + p.parseListeners = append(p.parseListeners[0:idx], p.parseListeners[idx+1:]...) + + if len(p.parseListeners) == 0 { + p.parseListeners = nil + } + } +} + +// Remove all parse listeners. +func (p *BaseParser) removeParseListeners() { + p.parseListeners = nil +} + +// TriggerEnterRuleEvent notifies all parse listeners of an enter rule event. +func (p *BaseParser) TriggerEnterRuleEvent() { + if p.parseListeners != nil { + ctx := p.ctx + for _, listener := range p.parseListeners { + listener.EnterEveryRule(ctx) + ctx.EnterRule(listener) + } + } +} + +// TriggerExitRuleEvent notifies any parse listeners of an exit rule event. +func (p *BaseParser) TriggerExitRuleEvent() { + if p.parseListeners != nil { + // reverse order walk of listeners + ctx := p.ctx + l := len(p.parseListeners) - 1 + + for i := range p.parseListeners { + listener := p.parseListeners[l-i] + ctx.ExitRule(listener) + listener.ExitEveryRule(ctx) + } + } +} + +func (p *BaseParser) GetInterpreter() *ParserATNSimulator { + return p.Interpreter +} + +func (p *BaseParser) GetATN() *ATN { + return p.Interpreter.atn +} + +func (p *BaseParser) GetTokenFactory() TokenFactory { + return p.input.GetTokenSource().GetTokenFactory() +} + +// setTokenFactory is used to tell our token source and error strategy about a new way to create tokens. +func (p *BaseParser) setTokenFactory(factory TokenFactory) { + p.input.GetTokenSource().setTokenFactory(factory) +} + +// GetATNWithBypassAlts - the ATN with bypass alternatives is expensive to create, so we create it +// lazily. +func (p *BaseParser) GetATNWithBypassAlts() { + + // TODO - Implement this? + panic("Not implemented!") + + // serializedAtn := p.getSerializedATN() + // if (serializedAtn == nil) { + // panic("The current parser does not support an ATN with bypass alternatives.") + // } + // result := p.bypassAltsAtnCache[serializedAtn] + // if (result == nil) { + // deserializationOptions := NewATNDeserializationOptions(nil) + // deserializationOptions.generateRuleBypassTransitions = true + // result = NewATNDeserializer(deserializationOptions).deserialize(serializedAtn) + // p.bypassAltsAtnCache[serializedAtn] = result + // } + // return result +} + +// The preferred method of getting a tree pattern. For example, here's a +// sample use: +// +// <pre> +// ParseTree t = parser.expr() +// ParseTreePattern p = parser.compileParseTreePattern("<ID>+0", +// MyParser.RULE_expr) +// ParseTreeMatch m = p.Match(t) +// String id = m.Get("ID") +// </pre> + +//goland:noinspection GoUnusedParameter +func (p *BaseParser) compileParseTreePattern(pattern, patternRuleIndex, lexer Lexer) { + + panic("NewParseTreePatternMatcher not implemented!") + // + // if (lexer == nil) { + // if (p.GetTokenStream() != nil) { + // tokenSource := p.GetTokenStream().GetTokenSource() + // if _, ok := tokenSource.(ILexer); ok { + // lexer = tokenSource + // } + // } + // } + // if (lexer == nil) { + // panic("Parser can't discover a lexer to use") + // } + + // m := NewParseTreePatternMatcher(lexer, p) + // return m.compile(pattern, patternRuleIndex) +} + +func (p *BaseParser) GetInputStream() IntStream { + return p.GetTokenStream() +} + +func (p *BaseParser) SetInputStream(input TokenStream) { + p.SetTokenStream(input) +} + +func (p *BaseParser) GetTokenStream() TokenStream { + return p.input +} + +// SetTokenStream installs input as the token stream and resets the parser. +func (p *BaseParser) SetTokenStream(input TokenStream) { + p.input = nil + p.reset() + p.input = input +} + +// GetCurrentToken returns the current token at LT(1). +// +// [Match] needs to return the current input symbol, which gets put +// into the label for the associated token ref e.g., x=ID. +func (p *BaseParser) GetCurrentToken() Token { + return p.input.LT(1) +} + +func (p *BaseParser) NotifyErrorListeners(msg string, offendingToken Token, err RecognitionException) { + if offendingToken == nil { + offendingToken = p.GetCurrentToken() + } + p._SyntaxErrors++ + line := offendingToken.GetLine() + column := offendingToken.GetColumn() + listener := p.GetErrorListenerDispatch() + listener.SyntaxError(p, offendingToken, line, column, msg, err) +} + +func (p *BaseParser) Consume() Token { + o := p.GetCurrentToken() + if o.GetTokenType() != TokenEOF { + p.GetInputStream().Consume() + } + hasListener := p.parseListeners != nil && len(p.parseListeners) > 0 + if p.BuildParseTrees || hasListener { + if p.errHandler.InErrorRecoveryMode(p) { + node := p.ctx.AddErrorNode(o) + if p.parseListeners != nil { + for _, l := range p.parseListeners { + l.VisitErrorNode(node) + } + } + + } else { + node := p.ctx.AddTokenNode(o) + if p.parseListeners != nil { + for _, l := range p.parseListeners { + l.VisitTerminal(node) + } + } + } + // node.invokingState = p.state + } + + return o +} + +func (p *BaseParser) addContextToParseTree() { + // add current context to parent if we have a parent + if p.ctx.GetParent() != nil { + p.ctx.GetParent().(ParserRuleContext).AddChild(p.ctx) + } +} + +func (p *BaseParser) EnterRule(localctx ParserRuleContext, state, _ int) { + p.SetState(state) + p.ctx = localctx + p.ctx.SetStart(p.input.LT(1)) + if p.BuildParseTrees { + p.addContextToParseTree() + } + if p.parseListeners != nil { + p.TriggerEnterRuleEvent() + } +} + +func (p *BaseParser) ExitRule() { + p.ctx.SetStop(p.input.LT(-1)) + // trigger event on ctx, before it reverts to parent + if p.parseListeners != nil { + p.TriggerExitRuleEvent() + } + p.SetState(p.ctx.GetInvokingState()) + if p.ctx.GetParent() != nil { + p.ctx = p.ctx.GetParent().(ParserRuleContext) + } else { + p.ctx = nil + } +} + +func (p *BaseParser) EnterOuterAlt(localctx ParserRuleContext, altNum int) { + localctx.SetAltNumber(altNum) + // if we have a new localctx, make sure we replace existing ctx + // that is previous child of parse tree + if p.BuildParseTrees && p.ctx != localctx { + if p.ctx.GetParent() != nil { + p.ctx.GetParent().(ParserRuleContext).RemoveLastChild() + p.ctx.GetParent().(ParserRuleContext).AddChild(localctx) + } + } + p.ctx = localctx +} + +// Get the precedence level for the top-most precedence rule. +// +// @return The precedence level for the top-most precedence rule, or -1 if +// the parser context is not nested within a precedence rule. + +func (p *BaseParser) GetPrecedence() int { + if len(p.precedenceStack) == 0 { + return -1 + } + + return p.precedenceStack[len(p.precedenceStack)-1] +} + +func (p *BaseParser) EnterRecursionRule(localctx ParserRuleContext, state, _, precedence int) { + p.SetState(state) + p.precedenceStack.Push(precedence) + p.ctx = localctx + p.ctx.SetStart(p.input.LT(1)) + if p.parseListeners != nil { + p.TriggerEnterRuleEvent() // simulates rule entry for + // left-recursive rules + } +} + +// +// Like {@link //EnterRule} but for recursive rules. + +func (p *BaseParser) PushNewRecursionContext(localctx ParserRuleContext, state, _ int) { + previous := p.ctx + previous.SetParent(localctx) + previous.SetInvokingState(state) + previous.SetStop(p.input.LT(-1)) + + p.ctx = localctx + p.ctx.SetStart(previous.GetStart()) + if p.BuildParseTrees { + p.ctx.AddChild(previous) + } + if p.parseListeners != nil { + p.TriggerEnterRuleEvent() // simulates rule entry for + // left-recursive rules + } +} + +func (p *BaseParser) UnrollRecursionContexts(parentCtx ParserRuleContext) { + _, _ = p.precedenceStack.Pop() + p.ctx.SetStop(p.input.LT(-1)) + retCtx := p.ctx // save current ctx (return value) + // unroll so ctx is as it was before call to recursive method + if p.parseListeners != nil { + for p.ctx != parentCtx { + p.TriggerExitRuleEvent() + p.ctx = p.ctx.GetParent().(ParserRuleContext) + } + } else { + p.ctx = parentCtx + } + // hook into tree + retCtx.SetParent(parentCtx) + if p.BuildParseTrees && parentCtx != nil { + // add return ctx into invoking rule's tree + parentCtx.AddChild(retCtx) + } +} + +func (p *BaseParser) GetInvokingContext(ruleIndex int) ParserRuleContext { + ctx := p.ctx + for ctx != nil { + if ctx.GetRuleIndex() == ruleIndex { + return ctx + } + ctx = ctx.GetParent().(ParserRuleContext) + } + return nil +} + +func (p *BaseParser) Precpred(_ RuleContext, precedence int) bool { + return precedence >= p.precedenceStack[len(p.precedenceStack)-1] +} + +//goland:noinspection GoUnusedParameter +func (p *BaseParser) inContext(context ParserRuleContext) bool { + // TODO: useful in parser? + return false +} + +// IsExpectedToken checks whether symbol can follow the current state in the +// {ATN}. The behavior of p.method is equivalent to the following, but is +// implemented such that the complete context-sensitive follow set does not +// need to be explicitly constructed. +// +// return getExpectedTokens().contains(symbol) +func (p *BaseParser) IsExpectedToken(symbol int) bool { + atn := p.Interpreter.atn + ctx := p.ctx + s := atn.states[p.state] + following := atn.NextTokens(s, nil) + if following.contains(symbol) { + return true + } + if !following.contains(TokenEpsilon) { + return false + } + for ctx != nil && ctx.GetInvokingState() >= 0 && following.contains(TokenEpsilon) { + invokingState := atn.states[ctx.GetInvokingState()] + rt := invokingState.GetTransitions()[0] + following = atn.NextTokens(rt.(*RuleTransition).followState, nil) + if following.contains(symbol) { + return true + } + ctx = ctx.GetParent().(ParserRuleContext) + } + if following.contains(TokenEpsilon) && symbol == TokenEOF { + return true + } + + return false +} + +// GetExpectedTokens and returns the set of input symbols which could follow the current parser +// state and context, as given by [GetState] and [GetContext], +// respectively. +func (p *BaseParser) GetExpectedTokens() *IntervalSet { + return p.Interpreter.atn.getExpectedTokens(p.state, p.ctx) +} + +func (p *BaseParser) GetExpectedTokensWithinCurrentRule() *IntervalSet { + atn := p.Interpreter.atn + s := atn.states[p.state] + return atn.NextTokens(s, nil) +} + +// GetRuleIndex get a rule's index (i.e., RULE_ruleName field) or -1 if not found. +func (p *BaseParser) GetRuleIndex(ruleName string) int { + var ruleIndex, ok = p.GetRuleIndexMap()[ruleName] + if ok { + return ruleIndex + } + + return -1 +} + +// GetRuleInvocationStack returns a list of the rule names in your parser instance +// leading up to a call to the current rule. You could override if +// you want more details such as the file/line info of where +// in the ATN a rule is invoked. +func (p *BaseParser) GetRuleInvocationStack(c ParserRuleContext) []string { + if c == nil { + c = p.ctx + } + stack := make([]string, 0) + for c != nil { + // compute what follows who invoked us + ruleIndex := c.GetRuleIndex() + if ruleIndex < 0 { + stack = append(stack, "n/a") + } else { + stack = append(stack, p.GetRuleNames()[ruleIndex]) + } + + vp := c.GetParent() + + if vp == nil { + break + } + + c = vp.(ParserRuleContext) + } + return stack +} + +// GetDFAStrings returns a list of all DFA states used for debugging purposes +func (p *BaseParser) GetDFAStrings() string { + return fmt.Sprint(p.Interpreter.decisionToDFA) +} + +// DumpDFA prints the whole of the DFA for debugging +func (p *BaseParser) DumpDFA() { + seenOne := false + for _, dfa := range p.Interpreter.decisionToDFA { + if dfa.Len() > 0 { + if seenOne { + fmt.Println() + } + fmt.Println("Decision " + strconv.Itoa(dfa.decision) + ":") + fmt.Print(dfa.String(p.LiteralNames, p.SymbolicNames)) + seenOne = true + } + } +} + +func (p *BaseParser) GetSourceName() string { + return p.GrammarFileName +} + +// SetTrace installs a trace listener for the parse. +// +// During a parse it is sometimes useful to listen in on the rule entry and exit +// events as well as token Matches. This is for quick and dirty debugging. +func (p *BaseParser) SetTrace(trace *TraceListener) { + if trace == nil { + p.RemoveParseListener(p.tracer) + p.tracer = nil + } else { + if p.tracer != nil { + p.RemoveParseListener(p.tracer) + } + p.tracer = NewTraceListener(p) + p.AddParseListener(p.tracer) + } +} |