107 lines
3.8 KiB
JavaScript
107 lines
3.8 KiB
JavaScript
|
|
||
|
import {ContextualKeyword} from "./keywords";
|
||
|
import { TokenType as tt} from "./types";
|
||
|
|
||
|
export class Scope {
|
||
|
|
||
|
|
||
|
|
||
|
|
||
|
constructor(startTokenIndex, endTokenIndex, isFunctionScope) {
|
||
|
this.startTokenIndex = startTokenIndex;
|
||
|
this.endTokenIndex = endTokenIndex;
|
||
|
this.isFunctionScope = isFunctionScope;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
export class StateSnapshot {
|
||
|
constructor(
|
||
|
potentialArrowAt,
|
||
|
noAnonFunctionType,
|
||
|
inDisallowConditionalTypesContext,
|
||
|
tokensLength,
|
||
|
scopesLength,
|
||
|
pos,
|
||
|
type,
|
||
|
contextualKeyword,
|
||
|
start,
|
||
|
end,
|
||
|
isType,
|
||
|
scopeDepth,
|
||
|
error,
|
||
|
) {;this.potentialArrowAt = potentialArrowAt;this.noAnonFunctionType = noAnonFunctionType;this.inDisallowConditionalTypesContext = inDisallowConditionalTypesContext;this.tokensLength = tokensLength;this.scopesLength = scopesLength;this.pos = pos;this.type = type;this.contextualKeyword = contextualKeyword;this.start = start;this.end = end;this.isType = isType;this.scopeDepth = scopeDepth;this.error = error;}
|
||
|
}
|
||
|
|
||
|
export default class State {constructor() { State.prototype.__init.call(this);State.prototype.__init2.call(this);State.prototype.__init3.call(this);State.prototype.__init4.call(this);State.prototype.__init5.call(this);State.prototype.__init6.call(this);State.prototype.__init7.call(this);State.prototype.__init8.call(this);State.prototype.__init9.call(this);State.prototype.__init10.call(this);State.prototype.__init11.call(this);State.prototype.__init12.call(this);State.prototype.__init13.call(this); }
|
||
|
// Used to signify the start of a potential arrow function
|
||
|
__init() {this.potentialArrowAt = -1}
|
||
|
|
||
|
// Used by Flow to handle an edge case involving function type parsing.
|
||
|
__init2() {this.noAnonFunctionType = false}
|
||
|
|
||
|
// Used by TypeScript to handle ambiguities when parsing conditional types.
|
||
|
__init3() {this.inDisallowConditionalTypesContext = false}
|
||
|
|
||
|
// Token store.
|
||
|
__init4() {this.tokens = []}
|
||
|
|
||
|
// Array of all observed scopes, ordered by their ending position.
|
||
|
__init5() {this.scopes = []}
|
||
|
|
||
|
// The current position of the tokenizer in the input.
|
||
|
__init6() {this.pos = 0}
|
||
|
|
||
|
// Information about the current token.
|
||
|
__init7() {this.type = tt.eof}
|
||
|
__init8() {this.contextualKeyword = ContextualKeyword.NONE}
|
||
|
__init9() {this.start = 0}
|
||
|
__init10() {this.end = 0}
|
||
|
|
||
|
__init11() {this.isType = false}
|
||
|
__init12() {this.scopeDepth = 0}
|
||
|
|
||
|
/**
|
||
|
* If the parser is in an error state, then the token is always tt.eof and all functions can
|
||
|
* keep executing but should be written so they don't get into an infinite loop in this situation.
|
||
|
*
|
||
|
* This approach, combined with the ability to snapshot and restore state, allows us to implement
|
||
|
* backtracking without exceptions and without needing to explicitly propagate error states
|
||
|
* everywhere.
|
||
|
*/
|
||
|
__init13() {this.error = null}
|
||
|
|
||
|
snapshot() {
|
||
|
return new StateSnapshot(
|
||
|
this.potentialArrowAt,
|
||
|
this.noAnonFunctionType,
|
||
|
this.inDisallowConditionalTypesContext,
|
||
|
this.tokens.length,
|
||
|
this.scopes.length,
|
||
|
this.pos,
|
||
|
this.type,
|
||
|
this.contextualKeyword,
|
||
|
this.start,
|
||
|
this.end,
|
||
|
this.isType,
|
||
|
this.scopeDepth,
|
||
|
this.error,
|
||
|
);
|
||
|
}
|
||
|
|
||
|
restoreFromSnapshot(snapshot) {
|
||
|
this.potentialArrowAt = snapshot.potentialArrowAt;
|
||
|
this.noAnonFunctionType = snapshot.noAnonFunctionType;
|
||
|
this.inDisallowConditionalTypesContext = snapshot.inDisallowConditionalTypesContext;
|
||
|
this.tokens.length = snapshot.tokensLength;
|
||
|
this.scopes.length = snapshot.scopesLength;
|
||
|
this.pos = snapshot.pos;
|
||
|
this.type = snapshot.type;
|
||
|
this.contextualKeyword = snapshot.contextualKeyword;
|
||
|
this.start = snapshot.start;
|
||
|
this.end = snapshot.end;
|
||
|
this.isType = snapshot.isType;
|
||
|
this.scopeDepth = snapshot.scopeDepth;
|
||
|
this.error = snapshot.error;
|
||
|
}
|
||
|
}
|