antlr4ts
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ANTLR 4 runtime for JavaScript written in Typescript
813 lines • 35.9 kB
JavaScript
"use strict";
/*!
* Copyright 2016 The ANTLR Project. All rights reserved.
* Licensed under the BSD-3-Clause license. See LICENSE file in the project root for license information.
*/
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Object.defineProperty(exports, "__esModule", { value: true });
exports.DefaultErrorStrategy = void 0;
const ATNState_1 = require("./atn/ATNState");
const ATNStateType_1 = require("./atn/ATNStateType");
const FailedPredicateException_1 = require("./FailedPredicateException");
const InputMismatchException_1 = require("./InputMismatchException");
const IntervalSet_1 = require("./misc/IntervalSet");
const NoViableAltException_1 = require("./NoViableAltException");
const PredictionContext_1 = require("./atn/PredictionContext");
const Token_1 = require("./Token");
const Decorators_1 = require("./Decorators");
/**
* This is the default implementation of {@link ANTLRErrorStrategy} used for
* error reporting and recovery in ANTLR parsers.
*/
class DefaultErrorStrategy {
constructor() {
/**
* Indicates whether the error strategy is currently "recovering from an
* error". This is used to suppress reporting multiple error messages while
* attempting to recover from a detected syntax error.
*
* @see #inErrorRecoveryMode
*/
this.errorRecoveryMode = false;
/** The index into the input stream where the last error occurred.
* This is used to prevent infinite loops where an error is found
* but no token is consumed during recovery...another error is found,
* ad nauseum. This is a failsafe mechanism to guarantee that at least
* one token/tree node is consumed for two errors.
*/
this.lastErrorIndex = -1;
/**
* @see #nextTokensContext
*/
this.nextTokensState = ATNState_1.ATNState.INVALID_STATE_NUMBER;
}
/**
* {@inheritDoc}
*
* The default implementation simply calls {@link #endErrorCondition} to
* ensure that the handler is not in error recovery mode.
*/
reset(recognizer) {
this.endErrorCondition(recognizer);
}
/**
* This method is called to enter error recovery mode when a recognition
* exception is reported.
*
* @param recognizer the parser instance
*/
beginErrorCondition(recognizer) {
this.errorRecoveryMode = true;
}
/**
* {@inheritDoc}
*/
inErrorRecoveryMode(recognizer) {
return this.errorRecoveryMode;
}
/**
* This method is called to leave error recovery mode after recovering from
* a recognition exception.
*
* @param recognizer
*/
endErrorCondition(recognizer) {
this.errorRecoveryMode = false;
this.lastErrorStates = undefined;
this.lastErrorIndex = -1;
}
/**
* {@inheritDoc}
*
* The default implementation simply calls {@link #endErrorCondition}.
*/
reportMatch(recognizer) {
this.endErrorCondition(recognizer);
}
/**
* {@inheritDoc}
*
* The default implementation returns immediately if the handler is already
* in error recovery mode. Otherwise, it calls {@link #beginErrorCondition}
* and dispatches the reporting task based on the runtime type of `e`
* according to the following table.
*
* * {@link NoViableAltException}: Dispatches the call to
* {@link #reportNoViableAlternative}
* * {@link InputMismatchException}: Dispatches the call to
* {@link #reportInputMismatch}
* * {@link FailedPredicateException}: Dispatches the call to
* {@link #reportFailedPredicate}
* * All other types: calls {@link Parser#notifyErrorListeners} to report
* the exception
*/
reportError(recognizer, e) {
// if we've already reported an error and have not matched a token
// yet successfully, don't report any errors.
if (this.inErrorRecoveryMode(recognizer)) {
// System.err.print("[SPURIOUS] ");
return; // don't report spurious errors
}
this.beginErrorCondition(recognizer);
if (e instanceof NoViableAltException_1.NoViableAltException) {
this.reportNoViableAlternative(recognizer, e);
}
else if (e instanceof InputMismatchException_1.InputMismatchException) {
this.reportInputMismatch(recognizer, e);
}
else if (e instanceof FailedPredicateException_1.FailedPredicateException) {
this.reportFailedPredicate(recognizer, e);
}
else {
console.error(`unknown recognition error type: ${e}`);
this.notifyErrorListeners(recognizer, e.toString(), e);
}
}
notifyErrorListeners(recognizer, message, e) {
let offendingToken = e.getOffendingToken(recognizer);
if (offendingToken === undefined) {
// Pass null to notifyErrorListeners so it in turn calls the error listeners with undefined as the offending
// token. If we passed undefined, it would instead call the listeners with currentToken from the parser.
offendingToken = null;
}
recognizer.notifyErrorListeners(message, offendingToken, e);
}
/**
* {@inheritDoc}
*
* The default implementation resynchronizes the parser by consuming tokens
* until we find one in the resynchronization set--loosely the set of tokens
* that can follow the current rule.
*/
recover(recognizer, e) {
// System.out.println("recover in "+recognizer.getRuleInvocationStack()+
// " index="+recognizer.inputStream.index+
// ", lastErrorIndex="+
// lastErrorIndex+
// ", states="+lastErrorStates);
if (this.lastErrorIndex === recognizer.inputStream.index &&
this.lastErrorStates &&
this.lastErrorStates.contains(recognizer.state)) {
// uh oh, another error at same token index and previously-visited
// state in ATN; must be a case where LT(1) is in the recovery
// token set so nothing got consumed. Consume a single token
// at least to prevent an infinite loop; this is a failsafe.
// System.err.println("seen error condition before index="+
// lastErrorIndex+", states="+lastErrorStates);
// System.err.println("FAILSAFE consumes "+recognizer.getTokenNames()[recognizer.inputStream.LA(1)]);
recognizer.consume();
}
this.lastErrorIndex = recognizer.inputStream.index;
if (!this.lastErrorStates) {
this.lastErrorStates = new IntervalSet_1.IntervalSet();
}
this.lastErrorStates.add(recognizer.state);
let followSet = this.getErrorRecoverySet(recognizer);
this.consumeUntil(recognizer, followSet);
}
/**
* The default implementation of {@link ANTLRErrorStrategy#sync} makes sure
* that the current lookahead symbol is consistent with what were expecting
* at this point in the ATN. You can call this anytime but ANTLR only
* generates code to check before subrules/loops and each iteration.
*
* Implements Jim Idle's magic sync mechanism in closures and optional
* subrules. E.g.,
*
* ```antlr
* a : sync ( stuff sync )* ;
* sync : {consume to what can follow sync} ;
* ```
*
* At the start of a sub rule upon error, {@link #sync} performs single
* token deletion, if possible. If it can't do that, it bails on the current
* rule and uses the default error recovery, which consumes until the
* resynchronization set of the current rule.
*
* If the sub rule is optional (`(...)?`, `(...)*`, or block
* with an empty alternative), then the expected set includes what follows
* the subrule.
*
* During loop iteration, it consumes until it sees a token that can start a
* sub rule or what follows loop. Yes, that is pretty aggressive. We opt to
* stay in the loop as long as possible.
*
* **ORIGINS**
*
* Previous versions of ANTLR did a poor job of their recovery within loops.
* A single mismatch token or missing token would force the parser to bail
* out of the entire rules surrounding the loop. So, for rule
*
* ```antlr
* classDef : 'class' ID '{' member* '}'
* ```
*
* input with an extra token between members would force the parser to
* consume until it found the next class definition rather than the next
* member definition of the current class.
*
* This functionality cost a little bit of effort because the parser has to
* compare token set at the start of the loop and at each iteration. If for
* some reason speed is suffering for you, you can turn off this
* functionality by simply overriding this method as a blank { }.
*/
sync(recognizer) {
let s = recognizer.interpreter.atn.states[recognizer.state];
// System.err.println("sync @ "+s.stateNumber+"="+s.getClass().getSimpleName());
// If already recovering, don't try to sync
if (this.inErrorRecoveryMode(recognizer)) {
return;
}
let tokens = recognizer.inputStream;
let la = tokens.LA(1);
// try cheaper subset first; might get lucky. seems to shave a wee bit off
let nextTokens = recognizer.atn.nextTokens(s);
if (nextTokens.contains(la)) {
// We are sure the token matches
this.nextTokensContext = undefined;
this.nextTokensState = ATNState_1.ATNState.INVALID_STATE_NUMBER;
return;
}
if (nextTokens.contains(Token_1.Token.EPSILON)) {
if (this.nextTokensContext === undefined) {
// It's possible the next token won't match; information tracked
// by sync is restricted for performance.
this.nextTokensContext = recognizer.context;
this.nextTokensState = recognizer.state;
}
return;
}
switch (s.stateType) {
case ATNStateType_1.ATNStateType.BLOCK_START:
case ATNStateType_1.ATNStateType.STAR_BLOCK_START:
case ATNStateType_1.ATNStateType.PLUS_BLOCK_START:
case ATNStateType_1.ATNStateType.STAR_LOOP_ENTRY:
// report error and recover if possible
if (this.singleTokenDeletion(recognizer)) {
return;
}
throw new InputMismatchException_1.InputMismatchException(recognizer);
case ATNStateType_1.ATNStateType.PLUS_LOOP_BACK:
case ATNStateType_1.ATNStateType.STAR_LOOP_BACK:
// System.err.println("at loop back: "+s.getClass().getSimpleName());
this.reportUnwantedToken(recognizer);
let expecting = recognizer.getExpectedTokens();
let whatFollowsLoopIterationOrRule = expecting.or(this.getErrorRecoverySet(recognizer));
this.consumeUntil(recognizer, whatFollowsLoopIterationOrRule);
break;
default:
// do nothing if we can't identify the exact kind of ATN state
break;
}
}
/**
* This is called by {@link #reportError} when the exception is a
* {@link NoViableAltException}.
*
* @see #reportError
*
* @param recognizer the parser instance
* @param e the recognition exception
*/
reportNoViableAlternative(recognizer, e) {
let tokens = recognizer.inputStream;
let input;
if (tokens) {
if (e.startToken.type === Token_1.Token.EOF) {
input = "<EOF>";
}
else {
input = tokens.getTextFromRange(e.startToken, e.getOffendingToken());
}
}
else {
input = "<unknown input>";
}
let msg = "no viable alternative at input " + this.escapeWSAndQuote(input);
this.notifyErrorListeners(recognizer, msg, e);
}
/**
* This is called by {@link #reportError} when the exception is an
* {@link InputMismatchException}.
*
* @see #reportError
*
* @param recognizer the parser instance
* @param e the recognition exception
*/
reportInputMismatch(recognizer, e) {
let expected = e.expectedTokens;
let expectedString = expected ? expected.toStringVocabulary(recognizer.vocabulary) : "";
let msg = "mismatched input " + this.getTokenErrorDisplay(e.getOffendingToken(recognizer)) +
" expecting " + expectedString;
this.notifyErrorListeners(recognizer, msg, e);
}
/**
* This is called by {@link #reportError} when the exception is a
* {@link FailedPredicateException}.
*
* @see #reportError
*
* @param recognizer the parser instance
* @param e the recognition exception
*/
reportFailedPredicate(recognizer, e) {
let ruleName = recognizer.ruleNames[recognizer.context.ruleIndex];
let msg = "rule " + ruleName + " " + e.message;
this.notifyErrorListeners(recognizer, msg, e);
}
/**
* This method is called to report a syntax error which requires the removal
* of a token from the input stream. At the time this method is called, the
* erroneous symbol is current `LT(1)` symbol and has not yet been
* removed from the input stream. When this method returns,
* `recognizer` is in error recovery mode.
*
* This method is called when {@link #singleTokenDeletion} identifies
* single-token deletion as a viable recovery strategy for a mismatched
* input error.
*
* The default implementation simply returns if the handler is already in
* error recovery mode. Otherwise, it calls {@link #beginErrorCondition} to
* enter error recovery mode, followed by calling
* {@link Parser#notifyErrorListeners}.
*
* @param recognizer the parser instance
*/
reportUnwantedToken(recognizer) {
if (this.inErrorRecoveryMode(recognizer)) {
return;
}
this.beginErrorCondition(recognizer);
let t = recognizer.currentToken;
let tokenName = this.getTokenErrorDisplay(t);
let expecting = this.getExpectedTokens(recognizer);
let msg = "extraneous input " + tokenName + " expecting " +
expecting.toStringVocabulary(recognizer.vocabulary);
recognizer.notifyErrorListeners(msg, t, undefined);
}
/**
* This method is called to report a syntax error which requires the
* insertion of a missing token into the input stream. At the time this
* method is called, the missing token has not yet been inserted. When this
* method returns, `recognizer` is in error recovery mode.
*
* This method is called when {@link #singleTokenInsertion} identifies
* single-token insertion as a viable recovery strategy for a mismatched
* input error.
*
* The default implementation simply returns if the handler is already in
* error recovery mode. Otherwise, it calls {@link #beginErrorCondition} to
* enter error recovery mode, followed by calling
* {@link Parser#notifyErrorListeners}.
*
* @param recognizer the parser instance
*/
reportMissingToken(recognizer) {
if (this.inErrorRecoveryMode(recognizer)) {
return;
}
this.beginErrorCondition(recognizer);
let t = recognizer.currentToken;
let expecting = this.getExpectedTokens(recognizer);
let msg = "missing " + expecting.toStringVocabulary(recognizer.vocabulary) +
" at " + this.getTokenErrorDisplay(t);
recognizer.notifyErrorListeners(msg, t, undefined);
}
/**
* {@inheritDoc}
*
* The default implementation attempts to recover from the mismatched input
* by using single token insertion and deletion as described below. If the
* recovery attempt fails, this method
* {@link InputMismatchException}.
*
* **EXTRA TOKEN** (single token deletion)
*
* `LA(1)` is not what we are looking for. If `LA(2)` has the
* right token, however, then assume `LA(1)` is some extra spurious
* token and delete it. Then consume and return the next token (which was
* the `LA(2)` token) as the successful result of the match operation.
*
* This recovery strategy is implemented by {@link #singleTokenDeletion}.
*
* **MISSING TOKEN** (single token insertion)
*
* If current token (at `LA(1)`) is consistent with what could come
* after the expected `LA(1)` token, then assume the token is missing
* and use the parser's {@link TokenFactory} to create it on the fly. The
* "insertion" is performed by returning the created token as the successful
* result of the match operation.
*
* This recovery strategy is implemented by {@link #singleTokenInsertion}.
*
* **EXAMPLE**
*
* For example, Input `i=(3;` is clearly missing the `')'`. When
* the parser returns from the nested call to `expr`, it will have
* call chain:
*
* ```
* stat → expr → atom
* ```
*
* and it will be trying to match the `')'` at this point in the
* derivation:
*
* ```
* => ID '=' '(' INT ')' ('+' atom)* ';'
* ^
* ```
*
* The attempt to match `')'` will fail when it sees `';'` and
* call {@link #recoverInline}. To recover, it sees that `LA(1)==';'`
* is in the set of tokens that can follow the `')'` token reference
* in rule `atom`. It can assume that you forgot the `')'`.
*/
recoverInline(recognizer) {
// SINGLE TOKEN DELETION
let matchedSymbol = this.singleTokenDeletion(recognizer);
if (matchedSymbol) {
// we have deleted the extra token.
// now, move past ttype token as if all were ok
recognizer.consume();
return matchedSymbol;
}
// SINGLE TOKEN INSERTION
if (this.singleTokenInsertion(recognizer)) {
return this.getMissingSymbol(recognizer);
}
// even that didn't work; must throw the exception
if (this.nextTokensContext === undefined) {
throw new InputMismatchException_1.InputMismatchException(recognizer);
}
else {
throw new InputMismatchException_1.InputMismatchException(recognizer, this.nextTokensState, this.nextTokensContext);
}
}
/**
* This method implements the single-token insertion inline error recovery
* strategy. It is called by {@link #recoverInline} if the single-token
* deletion strategy fails to recover from the mismatched input. If this
* method returns `true`, `recognizer` will be in error recovery
* mode.
*
* This method determines whether or not single-token insertion is viable by
* checking if the `LA(1)` input symbol could be successfully matched
* if it were instead the `LA(2)` symbol. If this method returns
* `true`, the caller is responsible for creating and inserting a
* token with the correct type to produce this behavior.
*
* @param recognizer the parser instance
* @returns `true` if single-token insertion is a viable recovery
* strategy for the current mismatched input, otherwise `false`
*/
singleTokenInsertion(recognizer) {
let currentSymbolType = recognizer.inputStream.LA(1);
// if current token is consistent with what could come after current
// ATN state, then we know we're missing a token; error recovery
// is free to conjure up and insert the missing token
let currentState = recognizer.interpreter.atn.states[recognizer.state];
let next = currentState.transition(0).target;
let atn = recognizer.interpreter.atn;
let expectingAtLL2 = atn.nextTokens(next, PredictionContext_1.PredictionContext.fromRuleContext(atn, recognizer.context));
// console.warn("LT(2) set="+expectingAtLL2.toString(recognizer.getTokenNames()));
if (expectingAtLL2.contains(currentSymbolType)) {
this.reportMissingToken(recognizer);
return true;
}
return false;
}
/**
* This method implements the single-token deletion inline error recovery
* strategy. It is called by {@link #recoverInline} to attempt to recover
* from mismatched input. If this method returns `undefined`, the parser and error
* handler state will not have changed. If this method returns non-`undefined`,
* `recognizer` will *not* be in error recovery mode since the
* returned token was a successful match.
*
* If the single-token deletion is successful, this method calls
* {@link #reportUnwantedToken} to report the error, followed by
* {@link Parser#consume} to actually "delete" the extraneous token. Then,
* before returning {@link #reportMatch} is called to signal a successful
* match.
*
* @param recognizer the parser instance
* @returns the successfully matched {@link Token} instance if single-token
* deletion successfully recovers from the mismatched input, otherwise
* `undefined`
*/
singleTokenDeletion(recognizer) {
let nextTokenType = recognizer.inputStream.LA(2);
let expecting = this.getExpectedTokens(recognizer);
if (expecting.contains(nextTokenType)) {
this.reportUnwantedToken(recognizer);
/*
System.err.println("recoverFromMismatchedToken deleting "+
((TokenStream)recognizer.inputStream).LT(1)+
" since "+((TokenStream)recognizer.inputStream).LT(2)+
" is what we want");
*/
recognizer.consume(); // simply delete extra token
// we want to return the token we're actually matching
let matchedSymbol = recognizer.currentToken;
this.reportMatch(recognizer); // we know current token is correct
return matchedSymbol;
}
return undefined;
}
/** Conjure up a missing token during error recovery.
*
* The recognizer attempts to recover from single missing
* symbols. But, actions might refer to that missing symbol.
* For example, x=ID {f($x);}. The action clearly assumes
* that there has been an identifier matched previously and that
* $x points at that token. If that token is missing, but
* the next token in the stream is what we want we assume that
* this token is missing and we keep going. Because we
* have to return some token to replace the missing token,
* we have to conjure one up. This method gives the user control
* over the tokens returned for missing tokens. Mostly,
* you will want to create something special for identifier
* tokens. For literals such as '{' and ',', the default
* action in the parser or tree parser works. It simply creates
* a CommonToken of the appropriate type. The text will be the token.
* If you change what tokens must be created by the lexer,
* override this method to create the appropriate tokens.
*/
getMissingSymbol(recognizer) {
let currentSymbol = recognizer.currentToken;
let expecting = this.getExpectedTokens(recognizer);
let expectedTokenType = Token_1.Token.INVALID_TYPE;
if (!expecting.isNil) {
// get any element
expectedTokenType = expecting.minElement;
}
let tokenText;
if (expectedTokenType === Token_1.Token.EOF) {
tokenText = "<missing EOF>";
}
else {
tokenText = "<missing " + recognizer.vocabulary.getDisplayName(expectedTokenType) + ">";
}
let current = currentSymbol;
let lookback = recognizer.inputStream.tryLT(-1);
if (current.type === Token_1.Token.EOF && lookback != null) {
current = lookback;
}
return this.constructToken(recognizer.inputStream.tokenSource, expectedTokenType, tokenText, current);
}
constructToken(tokenSource, expectedTokenType, tokenText, current) {
let factory = tokenSource.tokenFactory;
let x = current.tokenSource;
let stream = x ? x.inputStream : undefined;
return factory.create({ source: tokenSource, stream }, expectedTokenType, tokenText, Token_1.Token.DEFAULT_CHANNEL, -1, -1, current.line, current.charPositionInLine);
}
getExpectedTokens(recognizer) {
return recognizer.getExpectedTokens();
}
/** How should a token be displayed in an error message? The default
* is to display just the text, but during development you might
* want to have a lot of information spit out. Override in that case
* to use t.toString() (which, for CommonToken, dumps everything about
* the token). This is better than forcing you to override a method in
* your token objects because you don't have to go modify your lexer
* so that it creates a new Java type.
*/
getTokenErrorDisplay(t) {
if (!t) {
return "<no token>";
}
let s = this.getSymbolText(t);
if (!s) {
if (this.getSymbolType(t) === Token_1.Token.EOF) {
s = "<EOF>";
}
else {
s = `<${this.getSymbolType(t)}>`;
}
}
return this.escapeWSAndQuote(s);
}
getSymbolText(symbol) {
return symbol.text;
}
getSymbolType(symbol) {
return symbol.type;
}
escapeWSAndQuote(s) {
// if ( s==null ) return s;
s = s.replace("\n", "\\n");
s = s.replace("\r", "\\r");
s = s.replace("\t", "\\t");
return "'" + s + "'";
}
/* Compute the error recovery set for the current rule. During
* rule invocation, the parser pushes the set of tokens that can
* follow that rule reference on the stack; this amounts to
* computing FIRST of what follows the rule reference in the
* enclosing rule. See LinearApproximator.FIRST().
* This local follow set only includes tokens
* from within the rule; i.e., the FIRST computation done by
* ANTLR stops at the end of a rule.
*
* EXAMPLE
*
* When you find a "no viable alt exception", the input is not
* consistent with any of the alternatives for rule r. The best
* thing to do is to consume tokens until you see something that
* can legally follow a call to r *or* any rule that called r.
* You don't want the exact set of viable next tokens because the
* input might just be missing a token--you might consume the
* rest of the input looking for one of the missing tokens.
*
* Consider grammar:
*
* a : '[' b ']'
* | '(' b ')'
* ;
* b : c '^' INT ;
* c : ID
* | INT
* ;
*
* At each rule invocation, the set of tokens that could follow
* that rule is pushed on a stack. Here are the various
* context-sensitive follow sets:
*
* FOLLOW(b1_in_a) = FIRST(']') = ']'
* FOLLOW(b2_in_a) = FIRST(')') = ')'
* FOLLOW(c_in_b) = FIRST('^') = '^'
*
* Upon erroneous input "[]", the call chain is
*
* a -> b -> c
*
* and, hence, the follow context stack is:
*
* depth follow set start of rule execution
* 0 <EOF> a (from main())
* 1 ']' b
* 2 '^' c
*
* Notice that ')' is not included, because b would have to have
* been called from a different context in rule a for ')' to be
* included.
*
* For error recovery, we cannot consider FOLLOW(c)
* (context-sensitive or otherwise). We need the combined set of
* all context-sensitive FOLLOW sets--the set of all tokens that
* could follow any reference in the call chain. We need to
* resync to one of those tokens. Note that FOLLOW(c)='^' and if
* we resync'd to that token, we'd consume until EOF. We need to
* sync to context-sensitive FOLLOWs for a, b, and c: {']','^'}.
* In this case, for input "[]", LA(1) is ']' and in the set, so we would
* not consume anything. After printing an error, rule c would
* return normally. Rule b would not find the required '^' though.
* At this point, it gets a mismatched token error and
* exception (since LA(1) is not in the viable following token
* set). The rule exception handler tries to recover, but finds
* the same recovery set and doesn't consume anything. Rule b
* exits normally returning to rule a. Now it finds the ']' (and
* with the successful match exits errorRecovery mode).
*
* So, you can see that the parser walks up the call chain looking
* for the token that was a member of the recovery set.
*
* Errors are not generated in errorRecovery mode.
*
* ANTLR's error recovery mechanism is based upon original ideas:
*
* "Algorithms + Data Structures = Programs" by Niklaus Wirth
*
* and
*
* "A note on error recovery in recursive descent parsers":
* http://portal.acm.org/citation.cfm?id=947902.947905
*
* Later, Josef Grosch had some good ideas:
*
* "Efficient and Comfortable Error Recovery in Recursive Descent
* Parsers":
* ftp://www.cocolab.com/products/cocktail/doca4.ps/ell.ps.zip
*
* Like Grosch I implement context-sensitive FOLLOW sets that are combined
* at run-time upon error to avoid overhead during parsing.
*/
getErrorRecoverySet(recognizer) {
let atn = recognizer.interpreter.atn;
let ctx = recognizer.context;
let recoverSet = new IntervalSet_1.IntervalSet();
while (ctx && ctx.invokingState >= 0) {
// compute what follows who invoked us
let invokingState = atn.states[ctx.invokingState];
let rt = invokingState.transition(0);
let follow = atn.nextTokens(rt.followState);
recoverSet.addAll(follow);
ctx = ctx._parent;
}
recoverSet.remove(Token_1.Token.EPSILON);
// System.out.println("recover set "+recoverSet.toString(recognizer.getTokenNames()));
return recoverSet;
}
/** Consume tokens until one matches the given token set. */
consumeUntil(recognizer, set) {
// System.err.println("consumeUntil("+set.toString(recognizer.getTokenNames())+")");
let ttype = recognizer.inputStream.LA(1);
while (ttype !== Token_1.Token.EOF && !set.contains(ttype)) {
//System.out.println("consume during recover LA(1)="+getTokenNames()[input.LA(1)]);
// recognizer.inputStream.consume();
recognizer.consume();
ttype = recognizer.inputStream.LA(1);
}
}
}
__decorate([
Decorators_1.Override
], DefaultErrorStrategy.prototype, "reset", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "beginErrorCondition", null);
__decorate([
Decorators_1.Override
], DefaultErrorStrategy.prototype, "inErrorRecoveryMode", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "endErrorCondition", null);
__decorate([
Decorators_1.Override
], DefaultErrorStrategy.prototype, "reportMatch", null);
__decorate([
Decorators_1.Override
], DefaultErrorStrategy.prototype, "reportError", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "notifyErrorListeners", null);
__decorate([
Decorators_1.Override
], DefaultErrorStrategy.prototype, "recover", null);
__decorate([
Decorators_1.Override
], DefaultErrorStrategy.prototype, "sync", null);
__decorate([
__param(0, Decorators_1.NotNull),
__param(1, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "reportNoViableAlternative", null);
__decorate([
__param(0, Decorators_1.NotNull),
__param(1, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "reportInputMismatch", null);
__decorate([
__param(0, Decorators_1.NotNull),
__param(1, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "reportFailedPredicate", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "reportUnwantedToken", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "reportMissingToken", null);
__decorate([
Decorators_1.Override
], DefaultErrorStrategy.prototype, "recoverInline", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "singleTokenInsertion", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "singleTokenDeletion", null);
__decorate([
Decorators_1.NotNull,
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "getMissingSymbol", null);
__decorate([
Decorators_1.NotNull,
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "getExpectedTokens", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "getSymbolText", null);
__decorate([
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "getSymbolType", null);
__decorate([
Decorators_1.NotNull,
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "escapeWSAndQuote", null);
__decorate([
Decorators_1.NotNull,
__param(0, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "getErrorRecoverySet", null);
__decorate([
__param(0, Decorators_1.NotNull), __param(1, Decorators_1.NotNull)
], DefaultErrorStrategy.prototype, "consumeUntil", null);
exports.DefaultErrorStrategy = DefaultErrorStrategy;
//# sourceMappingURL=DefaultErrorStrategy.js.map