code-server/lib/vscode/src/vs/base/common/json.ts
2021-02-09 16:08:37 +00:00

1357 lines
36 KiB
TypeScript

/*---------------------------------------------------------------------------------------------
* Copyright (c) Microsoft Corporation. All rights reserved.
* Licensed under the MIT License. See License.txt in the project root for license information.
*--------------------------------------------------------------------------------------------*/
export const enum ScanError {
None = 0,
UnexpectedEndOfComment = 1,
UnexpectedEndOfString = 2,
UnexpectedEndOfNumber = 3,
InvalidUnicode = 4,
InvalidEscapeCharacter = 5,
InvalidCharacter = 6
}
export const enum SyntaxKind {
OpenBraceToken = 1,
CloseBraceToken = 2,
OpenBracketToken = 3,
CloseBracketToken = 4,
CommaToken = 5,
ColonToken = 6,
NullKeyword = 7,
TrueKeyword = 8,
FalseKeyword = 9,
StringLiteral = 10,
NumericLiteral = 11,
LineCommentTrivia = 12,
BlockCommentTrivia = 13,
LineBreakTrivia = 14,
Trivia = 15,
Unknown = 16,
EOF = 17
}
/**
* The scanner object, representing a JSON scanner at a position in the input string.
*/
export interface JSONScanner {
/**
* Sets the scan position to a new offset. A call to 'scan' is needed to get the first token.
*/
setPosition(pos: number): void;
/**
* Read the next token. Returns the token code.
*/
scan(): SyntaxKind;
/**
* Returns the current scan position, which is after the last read token.
*/
getPosition(): number;
/**
* Returns the last read token.
*/
getToken(): SyntaxKind;
/**
* Returns the last read token value. The value for strings is the decoded string content. For numbers its of type number, for boolean it's true or false.
*/
getTokenValue(): string;
/**
* The start offset of the last read token.
*/
getTokenOffset(): number;
/**
* The length of the last read token.
*/
getTokenLength(): number;
/**
* An error code of the last scan.
*/
getTokenError(): ScanError;
}
export interface ParseError {
error: ParseErrorCode;
offset: number;
length: number;
}
export const enum ParseErrorCode {
InvalidSymbol = 1,
InvalidNumberFormat = 2,
PropertyNameExpected = 3,
ValueExpected = 4,
ColonExpected = 5,
CommaExpected = 6,
CloseBraceExpected = 7,
CloseBracketExpected = 8,
EndOfFileExpected = 9,
InvalidCommentToken = 10,
UnexpectedEndOfComment = 11,
UnexpectedEndOfString = 12,
UnexpectedEndOfNumber = 13,
InvalidUnicode = 14,
InvalidEscapeCharacter = 15,
InvalidCharacter = 16
}
export type NodeType = 'object' | 'array' | 'property' | 'string' | 'number' | 'boolean' | 'null';
export interface Node {
readonly type: NodeType;
readonly value?: any;
readonly offset: number;
readonly length: number;
readonly colonOffset?: number;
readonly parent?: Node;
readonly children?: Node[];
}
export type Segment = string | number;
export type JSONPath = Segment[];
export interface Location {
/**
* The previous property key or literal value (string, number, boolean or null) or undefined.
*/
previousNode?: Node;
/**
* The path describing the location in the JSON document. The path consists of a sequence strings
* representing an object property or numbers for array indices.
*/
path: JSONPath;
/**
* Matches the locations path against a pattern consisting of strings (for properties) and numbers (for array indices).
* '*' will match a single segment, of any property name or index.
* '**' will match a sequence of segments or no segment, of any property name or index.
*/
matches: (patterns: JSONPath) => boolean;
/**
* If set, the location's offset is at a property key.
*/
isAtPropertyKey: boolean;
}
export interface ParseOptions {
disallowComments?: boolean;
allowTrailingComma?: boolean;
allowEmptyContent?: boolean;
}
export namespace ParseOptions {
export const DEFAULT = {
allowTrailingComma: true
};
}
export interface JSONVisitor {
/**
* Invoked when an open brace is encountered and an object is started. The offset and length represent the location of the open brace.
*/
onObjectBegin?: (offset: number, length: number) => void;
/**
* Invoked when a property is encountered. The offset and length represent the location of the property name.
*/
onObjectProperty?: (property: string, offset: number, length: number) => void;
/**
* Invoked when a closing brace is encountered and an object is completed. The offset and length represent the location of the closing brace.
*/
onObjectEnd?: (offset: number, length: number) => void;
/**
* Invoked when an open bracket is encountered. The offset and length represent the location of the open bracket.
*/
onArrayBegin?: (offset: number, length: number) => void;
/**
* Invoked when a closing bracket is encountered. The offset and length represent the location of the closing bracket.
*/
onArrayEnd?: (offset: number, length: number) => void;
/**
* Invoked when a literal value is encountered. The offset and length represent the location of the literal value.
*/
onLiteralValue?: (value: any, offset: number, length: number) => void;
/**
* Invoked when a comma or colon separator is encountered. The offset and length represent the location of the separator.
*/
onSeparator?: (character: string, offset: number, length: number) => void;
/**
* When comments are allowed, invoked when a line or block comment is encountered. The offset and length represent the location of the comment.
*/
onComment?: (offset: number, length: number) => void;
/**
* Invoked on an error.
*/
onError?: (error: ParseErrorCode, offset: number, length: number) => void;
}
/**
* Creates a JSON scanner on the given text.
* If ignoreTrivia is set, whitespaces or comments are ignored.
*/
export function createScanner(text: string, ignoreTrivia: boolean = false): JSONScanner {
let pos = 0,
len = text.length,
value: string = '',
tokenOffset = 0,
token: SyntaxKind = SyntaxKind.Unknown,
scanError: ScanError = ScanError.None;
function scanHexDigits(count: number): number {
let digits = 0;
let hexValue = 0;
while (digits < count) {
const ch = text.charCodeAt(pos);
if (ch >= CharacterCodes._0 && ch <= CharacterCodes._9) {
hexValue = hexValue * 16 + ch - CharacterCodes._0;
}
else if (ch >= CharacterCodes.A && ch <= CharacterCodes.F) {
hexValue = hexValue * 16 + ch - CharacterCodes.A + 10;
}
else if (ch >= CharacterCodes.a && ch <= CharacterCodes.f) {
hexValue = hexValue * 16 + ch - CharacterCodes.a + 10;
}
else {
break;
}
pos++;
digits++;
}
if (digits < count) {
hexValue = -1;
}
return hexValue;
}
function setPosition(newPosition: number) {
pos = newPosition;
value = '';
tokenOffset = 0;
token = SyntaxKind.Unknown;
scanError = ScanError.None;
}
function scanNumber(): string {
const start = pos;
if (text.charCodeAt(pos) === CharacterCodes._0) {
pos++;
} else {
pos++;
while (pos < text.length && isDigit(text.charCodeAt(pos))) {
pos++;
}
}
if (pos < text.length && text.charCodeAt(pos) === CharacterCodes.dot) {
pos++;
if (pos < text.length && isDigit(text.charCodeAt(pos))) {
pos++;
while (pos < text.length && isDigit(text.charCodeAt(pos))) {
pos++;
}
} else {
scanError = ScanError.UnexpectedEndOfNumber;
return text.substring(start, pos);
}
}
let end = pos;
if (pos < text.length && (text.charCodeAt(pos) === CharacterCodes.E || text.charCodeAt(pos) === CharacterCodes.e)) {
pos++;
if (pos < text.length && text.charCodeAt(pos) === CharacterCodes.plus || text.charCodeAt(pos) === CharacterCodes.minus) {
pos++;
}
if (pos < text.length && isDigit(text.charCodeAt(pos))) {
pos++;
while (pos < text.length && isDigit(text.charCodeAt(pos))) {
pos++;
}
end = pos;
} else {
scanError = ScanError.UnexpectedEndOfNumber;
}
}
return text.substring(start, end);
}
function scanString(): string {
let result = '',
start = pos;
while (true) {
if (pos >= len) {
result += text.substring(start, pos);
scanError = ScanError.UnexpectedEndOfString;
break;
}
const ch = text.charCodeAt(pos);
if (ch === CharacterCodes.doubleQuote) {
result += text.substring(start, pos);
pos++;
break;
}
if (ch === CharacterCodes.backslash) {
result += text.substring(start, pos);
pos++;
if (pos >= len) {
scanError = ScanError.UnexpectedEndOfString;
break;
}
const ch2 = text.charCodeAt(pos++);
switch (ch2) {
case CharacterCodes.doubleQuote:
result += '\"';
break;
case CharacterCodes.backslash:
result += '\\';
break;
case CharacterCodes.slash:
result += '/';
break;
case CharacterCodes.b:
result += '\b';
break;
case CharacterCodes.f:
result += '\f';
break;
case CharacterCodes.n:
result += '\n';
break;
case CharacterCodes.r:
result += '\r';
break;
case CharacterCodes.t:
result += '\t';
break;
case CharacterCodes.u:
const ch3 = scanHexDigits(4);
if (ch3 >= 0) {
result += String.fromCharCode(ch3);
} else {
scanError = ScanError.InvalidUnicode;
}
break;
default:
scanError = ScanError.InvalidEscapeCharacter;
}
start = pos;
continue;
}
if (ch >= 0 && ch <= 0x1F) {
if (isLineBreak(ch)) {
result += text.substring(start, pos);
scanError = ScanError.UnexpectedEndOfString;
break;
} else {
scanError = ScanError.InvalidCharacter;
// mark as error but continue with string
}
}
pos++;
}
return result;
}
function scanNext(): SyntaxKind {
value = '';
scanError = ScanError.None;
tokenOffset = pos;
if (pos >= len) {
// at the end
tokenOffset = len;
return token = SyntaxKind.EOF;
}
let code = text.charCodeAt(pos);
// trivia: whitespace
if (isWhitespace(code)) {
do {
pos++;
value += String.fromCharCode(code);
code = text.charCodeAt(pos);
} while (isWhitespace(code));
return token = SyntaxKind.Trivia;
}
// trivia: newlines
if (isLineBreak(code)) {
pos++;
value += String.fromCharCode(code);
if (code === CharacterCodes.carriageReturn && text.charCodeAt(pos) === CharacterCodes.lineFeed) {
pos++;
value += '\n';
}
return token = SyntaxKind.LineBreakTrivia;
}
switch (code) {
// tokens: []{}:,
case CharacterCodes.openBrace:
pos++;
return token = SyntaxKind.OpenBraceToken;
case CharacterCodes.closeBrace:
pos++;
return token = SyntaxKind.CloseBraceToken;
case CharacterCodes.openBracket:
pos++;
return token = SyntaxKind.OpenBracketToken;
case CharacterCodes.closeBracket:
pos++;
return token = SyntaxKind.CloseBracketToken;
case CharacterCodes.colon:
pos++;
return token = SyntaxKind.ColonToken;
case CharacterCodes.comma:
pos++;
return token = SyntaxKind.CommaToken;
// strings
case CharacterCodes.doubleQuote:
pos++;
value = scanString();
return token = SyntaxKind.StringLiteral;
// comments
case CharacterCodes.slash:
const start = pos - 1;
// Single-line comment
if (text.charCodeAt(pos + 1) === CharacterCodes.slash) {
pos += 2;
while (pos < len) {
if (isLineBreak(text.charCodeAt(pos))) {
break;
}
pos++;
}
value = text.substring(start, pos);
return token = SyntaxKind.LineCommentTrivia;
}
// Multi-line comment
if (text.charCodeAt(pos + 1) === CharacterCodes.asterisk) {
pos += 2;
const safeLength = len - 1; // For lookahead.
let commentClosed = false;
while (pos < safeLength) {
const ch = text.charCodeAt(pos);
if (ch === CharacterCodes.asterisk && text.charCodeAt(pos + 1) === CharacterCodes.slash) {
pos += 2;
commentClosed = true;
break;
}
pos++;
}
if (!commentClosed) {
pos++;
scanError = ScanError.UnexpectedEndOfComment;
}
value = text.substring(start, pos);
return token = SyntaxKind.BlockCommentTrivia;
}
// just a single slash
value += String.fromCharCode(code);
pos++;
return token = SyntaxKind.Unknown;
// numbers
case CharacterCodes.minus:
value += String.fromCharCode(code);
pos++;
if (pos === len || !isDigit(text.charCodeAt(pos))) {
return token = SyntaxKind.Unknown;
}
// found a minus, followed by a number so
// we fall through to proceed with scanning
// numbers
case CharacterCodes._0:
case CharacterCodes._1:
case CharacterCodes._2:
case CharacterCodes._3:
case CharacterCodes._4:
case CharacterCodes._5:
case CharacterCodes._6:
case CharacterCodes._7:
case CharacterCodes._8:
case CharacterCodes._9:
value += scanNumber();
return token = SyntaxKind.NumericLiteral;
// literals and unknown symbols
default:
// is a literal? Read the full word.
while (pos < len && isUnknownContentCharacter(code)) {
pos++;
code = text.charCodeAt(pos);
}
if (tokenOffset !== pos) {
value = text.substring(tokenOffset, pos);
// keywords: true, false, null
switch (value) {
case 'true': return token = SyntaxKind.TrueKeyword;
case 'false': return token = SyntaxKind.FalseKeyword;
case 'null': return token = SyntaxKind.NullKeyword;
}
return token = SyntaxKind.Unknown;
}
// some
value += String.fromCharCode(code);
pos++;
return token = SyntaxKind.Unknown;
}
}
function isUnknownContentCharacter(code: CharacterCodes) {
if (isWhitespace(code) || isLineBreak(code)) {
return false;
}
switch (code) {
case CharacterCodes.closeBrace:
case CharacterCodes.closeBracket:
case CharacterCodes.openBrace:
case CharacterCodes.openBracket:
case CharacterCodes.doubleQuote:
case CharacterCodes.colon:
case CharacterCodes.comma:
case CharacterCodes.slash:
return false;
}
return true;
}
function scanNextNonTrivia(): SyntaxKind {
let result: SyntaxKind;
do {
result = scanNext();
} while (result >= SyntaxKind.LineCommentTrivia && result <= SyntaxKind.Trivia);
return result;
}
return {
setPosition: setPosition,
getPosition: () => pos,
scan: ignoreTrivia ? scanNextNonTrivia : scanNext,
getToken: () => token,
getTokenValue: () => value,
getTokenOffset: () => tokenOffset,
getTokenLength: () => pos - tokenOffset,
getTokenError: () => scanError
};
}
function isWhitespace(ch: number): boolean {
return ch === CharacterCodes.space || ch === CharacterCodes.tab || ch === CharacterCodes.verticalTab || ch === CharacterCodes.formFeed ||
ch === CharacterCodes.nonBreakingSpace || ch === CharacterCodes.ogham || ch >= CharacterCodes.enQuad && ch <= CharacterCodes.zeroWidthSpace ||
ch === CharacterCodes.narrowNoBreakSpace || ch === CharacterCodes.mathematicalSpace || ch === CharacterCodes.ideographicSpace || ch === CharacterCodes.byteOrderMark;
}
function isLineBreak(ch: number): boolean {
return ch === CharacterCodes.lineFeed || ch === CharacterCodes.carriageReturn || ch === CharacterCodes.lineSeparator || ch === CharacterCodes.paragraphSeparator;
}
function isDigit(ch: number): boolean {
return ch >= CharacterCodes._0 && ch <= CharacterCodes._9;
}
const enum CharacterCodes {
nullCharacter = 0,
maxAsciiCharacter = 0x7F,
lineFeed = 0x0A, // \n
carriageReturn = 0x0D, // \r
lineSeparator = 0x2028,
paragraphSeparator = 0x2029,
// REVIEW: do we need to support this? The scanner doesn't, but our IText does. This seems
// like an odd disparity? (Or maybe it's completely fine for them to be different).
nextLine = 0x0085,
// Unicode 3.0 space characters
space = 0x0020, // " "
nonBreakingSpace = 0x00A0, //
enQuad = 0x2000,
emQuad = 0x2001,
enSpace = 0x2002,
emSpace = 0x2003,
threePerEmSpace = 0x2004,
fourPerEmSpace = 0x2005,
sixPerEmSpace = 0x2006,
figureSpace = 0x2007,
punctuationSpace = 0x2008,
thinSpace = 0x2009,
hairSpace = 0x200A,
zeroWidthSpace = 0x200B,
narrowNoBreakSpace = 0x202F,
ideographicSpace = 0x3000,
mathematicalSpace = 0x205F,
ogham = 0x1680,
_ = 0x5F,
$ = 0x24,
_0 = 0x30,
_1 = 0x31,
_2 = 0x32,
_3 = 0x33,
_4 = 0x34,
_5 = 0x35,
_6 = 0x36,
_7 = 0x37,
_8 = 0x38,
_9 = 0x39,
a = 0x61,
b = 0x62,
c = 0x63,
d = 0x64,
e = 0x65,
f = 0x66,
g = 0x67,
h = 0x68,
i = 0x69,
j = 0x6A,
k = 0x6B,
l = 0x6C,
m = 0x6D,
n = 0x6E,
o = 0x6F,
p = 0x70,
q = 0x71,
r = 0x72,
s = 0x73,
t = 0x74,
u = 0x75,
v = 0x76,
w = 0x77,
x = 0x78,
y = 0x79,
z = 0x7A,
A = 0x41,
B = 0x42,
C = 0x43,
D = 0x44,
E = 0x45,
F = 0x46,
G = 0x47,
H = 0x48,
I = 0x49,
J = 0x4A,
K = 0x4B,
L = 0x4C,
M = 0x4D,
N = 0x4E,
O = 0x4F,
P = 0x50,
Q = 0x51,
R = 0x52,
S = 0x53,
T = 0x54,
U = 0x55,
V = 0x56,
W = 0x57,
X = 0x58,
Y = 0x59,
Z = 0x5A,
ampersand = 0x26, // &
asterisk = 0x2A, // *
at = 0x40, // @
backslash = 0x5C, // \
bar = 0x7C, // |
caret = 0x5E, // ^
closeBrace = 0x7D, // }
closeBracket = 0x5D, // ]
closeParen = 0x29, // )
colon = 0x3A, // :
comma = 0x2C, // ,
dot = 0x2E, // .
doubleQuote = 0x22, // "
equals = 0x3D, // =
exclamation = 0x21, // !
greaterThan = 0x3E, // >
lessThan = 0x3C, // <
minus = 0x2D, // -
openBrace = 0x7B, // {
openBracket = 0x5B, // [
openParen = 0x28, // (
percent = 0x25, // %
plus = 0x2B, // +
question = 0x3F, // ?
semicolon = 0x3B, // ;
singleQuote = 0x27, // '
slash = 0x2F, // /
tilde = 0x7E, // ~
backspace = 0x08, // \b
formFeed = 0x0C, // \f
byteOrderMark = 0xFEFF,
tab = 0x09, // \t
verticalTab = 0x0B, // \v
}
interface NodeImpl extends Node {
type: NodeType;
value?: any;
offset: number;
length: number;
colonOffset?: number;
parent?: NodeImpl;
children?: NodeImpl[];
}
/**
* For a given offset, evaluate the location in the JSON document. Each segment in the location path is either a property name or an array index.
*/
export function getLocation(text: string, position: number): Location {
const segments: Segment[] = []; // strings or numbers
const earlyReturnException = new Object();
let previousNode: NodeImpl | undefined = undefined;
const previousNodeInst: NodeImpl = {
value: {},
offset: 0,
length: 0,
type: 'object',
parent: undefined
};
let isAtPropertyKey = false;
function setPreviousNode(value: string, offset: number, length: number, type: NodeType) {
previousNodeInst.value = value;
previousNodeInst.offset = offset;
previousNodeInst.length = length;
previousNodeInst.type = type;
previousNodeInst.colonOffset = undefined;
previousNode = previousNodeInst;
}
try {
visit(text, {
onObjectBegin: (offset: number, length: number) => {
if (position <= offset) {
throw earlyReturnException;
}
previousNode = undefined;
isAtPropertyKey = position > offset;
segments.push(''); // push a placeholder (will be replaced)
},
onObjectProperty: (name: string, offset: number, length: number) => {
if (position < offset) {
throw earlyReturnException;
}
setPreviousNode(name, offset, length, 'property');
segments[segments.length - 1] = name;
if (position <= offset + length) {
throw earlyReturnException;
}
},
onObjectEnd: (offset: number, length: number) => {
if (position <= offset) {
throw earlyReturnException;
}
previousNode = undefined;
segments.pop();
},
onArrayBegin: (offset: number, length: number) => {
if (position <= offset) {
throw earlyReturnException;
}
previousNode = undefined;
segments.push(0);
},
onArrayEnd: (offset: number, length: number) => {
if (position <= offset) {
throw earlyReturnException;
}
previousNode = undefined;
segments.pop();
},
onLiteralValue: (value: any, offset: number, length: number) => {
if (position < offset) {
throw earlyReturnException;
}
setPreviousNode(value, offset, length, getNodeType(value));
if (position <= offset + length) {
throw earlyReturnException;
}
},
onSeparator: (sep: string, offset: number, length: number) => {
if (position <= offset) {
throw earlyReturnException;
}
if (sep === ':' && previousNode && previousNode.type === 'property') {
previousNode.colonOffset = offset;
isAtPropertyKey = false;
previousNode = undefined;
} else if (sep === ',') {
const last = segments[segments.length - 1];
if (typeof last === 'number') {
segments[segments.length - 1] = last + 1;
} else {
isAtPropertyKey = true;
segments[segments.length - 1] = '';
}
previousNode = undefined;
}
}
});
} catch (e) {
if (e !== earlyReturnException) {
throw e;
}
}
return {
path: segments,
previousNode,
isAtPropertyKey,
matches: (pattern: Segment[]) => {
let k = 0;
for (let i = 0; k < pattern.length && i < segments.length; i++) {
if (pattern[k] === segments[i] || pattern[k] === '*') {
k++;
} else if (pattern[k] !== '**') {
return false;
}
}
return k === pattern.length;
}
};
}
/**
* Parses the given text and returns the object the JSON content represents. On invalid input, the parser tries to be as fault tolerant as possible, but still return a result.
* Therefore always check the errors list to find out if the input was valid.
*/
export function parse(text: string, errors: ParseError[] = [], options: ParseOptions = ParseOptions.DEFAULT): any {
let currentProperty: string | null = null;
let currentParent: any = [];
const previousParents: any[] = [];
function onValue(value: any) {
if (Array.isArray(currentParent)) {
(<any[]>currentParent).push(value);
} else if (currentProperty !== null) {
currentParent[currentProperty] = value;
}
}
const visitor: JSONVisitor = {
onObjectBegin: () => {
const object = {};
onValue(object);
previousParents.push(currentParent);
currentParent = object;
currentProperty = null;
},
onObjectProperty: (name: string) => {
currentProperty = name;
},
onObjectEnd: () => {
currentParent = previousParents.pop();
},
onArrayBegin: () => {
const array: any[] = [];
onValue(array);
previousParents.push(currentParent);
currentParent = array;
currentProperty = null;
},
onArrayEnd: () => {
currentParent = previousParents.pop();
},
onLiteralValue: onValue,
onError: (error: ParseErrorCode, offset: number, length: number) => {
errors.push({ error, offset, length });
}
};
visit(text, visitor, options);
return currentParent[0];
}
/**
* Parses the given text and returns a tree representation the JSON content. On invalid input, the parser tries to be as fault tolerant as possible, but still return a result.
*/
export function parseTree(text: string, errors: ParseError[] = [], options: ParseOptions = ParseOptions.DEFAULT): Node {
let currentParent: NodeImpl = { type: 'array', offset: -1, length: -1, children: [], parent: undefined }; // artificial root
function ensurePropertyComplete(endOffset: number) {
if (currentParent.type === 'property') {
currentParent.length = endOffset - currentParent.offset;
currentParent = currentParent.parent!;
}
}
function onValue(valueNode: Node): Node {
currentParent.children!.push(valueNode);
return valueNode;
}
const visitor: JSONVisitor = {
onObjectBegin: (offset: number) => {
currentParent = onValue({ type: 'object', offset, length: -1, parent: currentParent, children: [] });
},
onObjectProperty: (name: string, offset: number, length: number) => {
currentParent = onValue({ type: 'property', offset, length: -1, parent: currentParent, children: [] });
currentParent.children!.push({ type: 'string', value: name, offset, length, parent: currentParent });
},
onObjectEnd: (offset: number, length: number) => {
currentParent.length = offset + length - currentParent.offset;
currentParent = currentParent.parent!;
ensurePropertyComplete(offset + length);
},
onArrayBegin: (offset: number, length: number) => {
currentParent = onValue({ type: 'array', offset, length: -1, parent: currentParent, children: [] });
},
onArrayEnd: (offset: number, length: number) => {
currentParent.length = offset + length - currentParent.offset;
currentParent = currentParent.parent!;
ensurePropertyComplete(offset + length);
},
onLiteralValue: (value: any, offset: number, length: number) => {
onValue({ type: getNodeType(value), offset, length, parent: currentParent, value });
ensurePropertyComplete(offset + length);
},
onSeparator: (sep: string, offset: number, length: number) => {
if (currentParent.type === 'property') {
if (sep === ':') {
currentParent.colonOffset = offset;
} else if (sep === ',') {
ensurePropertyComplete(offset);
}
}
},
onError: (error: ParseErrorCode, offset: number, length: number) => {
errors.push({ error, offset, length });
}
};
visit(text, visitor, options);
const result = currentParent.children![0];
if (result) {
delete result.parent;
}
return result;
}
/**
* Finds the node at the given path in a JSON DOM.
*/
export function findNodeAtLocation(root: Node, path: JSONPath): Node | undefined {
if (!root) {
return undefined;
}
let node = root;
for (let segment of path) {
if (typeof segment === 'string') {
if (node.type !== 'object' || !Array.isArray(node.children)) {
return undefined;
}
let found = false;
for (const propertyNode of node.children) {
if (Array.isArray(propertyNode.children) && propertyNode.children[0].value === segment) {
node = propertyNode.children[1];
found = true;
break;
}
}
if (!found) {
return undefined;
}
} else {
const index = <number>segment;
if (node.type !== 'array' || index < 0 || !Array.isArray(node.children) || index >= node.children.length) {
return undefined;
}
node = node.children[index];
}
}
return node;
}
/**
* Gets the JSON path of the given JSON DOM node
*/
export function getNodePath(node: Node): JSONPath {
if (!node.parent || !node.parent.children) {
return [];
}
const path = getNodePath(node.parent);
if (node.parent.type === 'property') {
const key = node.parent.children[0].value;
path.push(key);
} else if (node.parent.type === 'array') {
const index = node.parent.children.indexOf(node);
if (index !== -1) {
path.push(index);
}
}
return path;
}
/**
* Evaluates the JavaScript object of the given JSON DOM node
*/
export function getNodeValue(node: Node): any {
switch (node.type) {
case 'array':
return node.children!.map(getNodeValue);
case 'object':
const obj = Object.create(null);
for (let prop of node.children!) {
const valueNode = prop.children![1];
if (valueNode) {
obj[prop.children![0].value] = getNodeValue(valueNode);
}
}
return obj;
case 'null':
case 'string':
case 'number':
case 'boolean':
return node.value;
default:
return undefined;
}
}
export function contains(node: Node, offset: number, includeRightBound = false): boolean {
return (offset >= node.offset && offset < (node.offset + node.length)) || includeRightBound && (offset === (node.offset + node.length));
}
/**
* Finds the most inner node at the given offset. If includeRightBound is set, also finds nodes that end at the given offset.
*/
export function findNodeAtOffset(node: Node, offset: number, includeRightBound = false): Node | undefined {
if (contains(node, offset, includeRightBound)) {
const children = node.children;
if (Array.isArray(children)) {
for (let i = 0; i < children.length && children[i].offset <= offset; i++) {
const item = findNodeAtOffset(children[i], offset, includeRightBound);
if (item) {
return item;
}
}
}
return node;
}
return undefined;
}
/**
* Parses the given text and invokes the visitor functions for each object, array and literal reached.
*/
export function visit(text: string, visitor: JSONVisitor, options: ParseOptions = ParseOptions.DEFAULT): any {
const _scanner = createScanner(text, false);
function toNoArgVisit(visitFunction?: (offset: number, length: number) => void): () => void {
return visitFunction ? () => visitFunction(_scanner.getTokenOffset(), _scanner.getTokenLength()) : () => true;
}
function toOneArgVisit<T>(visitFunction?: (arg: T, offset: number, length: number) => void): (arg: T) => void {
return visitFunction ? (arg: T) => visitFunction(arg, _scanner.getTokenOffset(), _scanner.getTokenLength()) : () => true;
}
const onObjectBegin = toNoArgVisit(visitor.onObjectBegin),
onObjectProperty = toOneArgVisit(visitor.onObjectProperty),
onObjectEnd = toNoArgVisit(visitor.onObjectEnd),
onArrayBegin = toNoArgVisit(visitor.onArrayBegin),
onArrayEnd = toNoArgVisit(visitor.onArrayEnd),
onLiteralValue = toOneArgVisit(visitor.onLiteralValue),
onSeparator = toOneArgVisit(visitor.onSeparator),
onComment = toNoArgVisit(visitor.onComment),
onError = toOneArgVisit(visitor.onError);
const disallowComments = options && options.disallowComments;
const allowTrailingComma = options && options.allowTrailingComma;
function scanNext(): SyntaxKind {
while (true) {
const token = _scanner.scan();
switch (_scanner.getTokenError()) {
case ScanError.InvalidUnicode:
handleError(ParseErrorCode.InvalidUnicode);
break;
case ScanError.InvalidEscapeCharacter:
handleError(ParseErrorCode.InvalidEscapeCharacter);
break;
case ScanError.UnexpectedEndOfNumber:
handleError(ParseErrorCode.UnexpectedEndOfNumber);
break;
case ScanError.UnexpectedEndOfComment:
if (!disallowComments) {
handleError(ParseErrorCode.UnexpectedEndOfComment);
}
break;
case ScanError.UnexpectedEndOfString:
handleError(ParseErrorCode.UnexpectedEndOfString);
break;
case ScanError.InvalidCharacter:
handleError(ParseErrorCode.InvalidCharacter);
break;
}
switch (token) {
case SyntaxKind.LineCommentTrivia:
case SyntaxKind.BlockCommentTrivia:
if (disallowComments) {
handleError(ParseErrorCode.InvalidCommentToken);
} else {
onComment();
}
break;
case SyntaxKind.Unknown:
handleError(ParseErrorCode.InvalidSymbol);
break;
case SyntaxKind.Trivia:
case SyntaxKind.LineBreakTrivia:
break;
default:
return token;
}
}
}
function handleError(error: ParseErrorCode, skipUntilAfter: SyntaxKind[] = [], skipUntil: SyntaxKind[] = []): void {
onError(error);
if (skipUntilAfter.length + skipUntil.length > 0) {
let token = _scanner.getToken();
while (token !== SyntaxKind.EOF) {
if (skipUntilAfter.indexOf(token) !== -1) {
scanNext();
break;
} else if (skipUntil.indexOf(token) !== -1) {
break;
}
token = scanNext();
}
}
}
function parseString(isValue: boolean): boolean {
const value = _scanner.getTokenValue();
if (isValue) {
onLiteralValue(value);
} else {
onObjectProperty(value);
}
scanNext();
return true;
}
function parseLiteral(): boolean {
switch (_scanner.getToken()) {
case SyntaxKind.NumericLiteral:
let value = 0;
try {
value = JSON.parse(_scanner.getTokenValue());
if (typeof value !== 'number') {
handleError(ParseErrorCode.InvalidNumberFormat);
value = 0;
}
} catch (e) {
handleError(ParseErrorCode.InvalidNumberFormat);
}
onLiteralValue(value);
break;
case SyntaxKind.NullKeyword:
onLiteralValue(null);
break;
case SyntaxKind.TrueKeyword:
onLiteralValue(true);
break;
case SyntaxKind.FalseKeyword:
onLiteralValue(false);
break;
default:
return false;
}
scanNext();
return true;
}
function parseProperty(): boolean {
if (_scanner.getToken() !== SyntaxKind.StringLiteral) {
handleError(ParseErrorCode.PropertyNameExpected, [], [SyntaxKind.CloseBraceToken, SyntaxKind.CommaToken]);
return false;
}
parseString(false);
if (_scanner.getToken() === SyntaxKind.ColonToken) {
onSeparator(':');
scanNext(); // consume colon
if (!parseValue()) {
handleError(ParseErrorCode.ValueExpected, [], [SyntaxKind.CloseBraceToken, SyntaxKind.CommaToken]);
}
} else {
handleError(ParseErrorCode.ColonExpected, [], [SyntaxKind.CloseBraceToken, SyntaxKind.CommaToken]);
}
return true;
}
function parseObject(): boolean {
onObjectBegin();
scanNext(); // consume open brace
let needsComma = false;
while (_scanner.getToken() !== SyntaxKind.CloseBraceToken && _scanner.getToken() !== SyntaxKind.EOF) {
if (_scanner.getToken() === SyntaxKind.CommaToken) {
if (!needsComma) {
handleError(ParseErrorCode.ValueExpected, [], []);
}
onSeparator(',');
scanNext(); // consume comma
if (_scanner.getToken() === SyntaxKind.CloseBraceToken && allowTrailingComma) {
break;
}
} else if (needsComma) {
handleError(ParseErrorCode.CommaExpected, [], []);
}
if (!parseProperty()) {
handleError(ParseErrorCode.ValueExpected, [], [SyntaxKind.CloseBraceToken, SyntaxKind.CommaToken]);
}
needsComma = true;
}
onObjectEnd();
if (_scanner.getToken() !== SyntaxKind.CloseBraceToken) {
handleError(ParseErrorCode.CloseBraceExpected, [SyntaxKind.CloseBraceToken], []);
} else {
scanNext(); // consume close brace
}
return true;
}
function parseArray(): boolean {
onArrayBegin();
scanNext(); // consume open bracket
let needsComma = false;
while (_scanner.getToken() !== SyntaxKind.CloseBracketToken && _scanner.getToken() !== SyntaxKind.EOF) {
if (_scanner.getToken() === SyntaxKind.CommaToken) {
if (!needsComma) {
handleError(ParseErrorCode.ValueExpected, [], []);
}
onSeparator(',');
scanNext(); // consume comma
if (_scanner.getToken() === SyntaxKind.CloseBracketToken && allowTrailingComma) {
break;
}
} else if (needsComma) {
handleError(ParseErrorCode.CommaExpected, [], []);
}
if (!parseValue()) {
handleError(ParseErrorCode.ValueExpected, [], [SyntaxKind.CloseBracketToken, SyntaxKind.CommaToken]);
}
needsComma = true;
}
onArrayEnd();
if (_scanner.getToken() !== SyntaxKind.CloseBracketToken) {
handleError(ParseErrorCode.CloseBracketExpected, [SyntaxKind.CloseBracketToken], []);
} else {
scanNext(); // consume close bracket
}
return true;
}
function parseValue(): boolean {
switch (_scanner.getToken()) {
case SyntaxKind.OpenBracketToken:
return parseArray();
case SyntaxKind.OpenBraceToken:
return parseObject();
case SyntaxKind.StringLiteral:
return parseString(true);
default:
return parseLiteral();
}
}
scanNext();
if (_scanner.getToken() === SyntaxKind.EOF) {
if (options.allowEmptyContent) {
return true;
}
handleError(ParseErrorCode.ValueExpected, [], []);
return false;
}
if (!parseValue()) {
handleError(ParseErrorCode.ValueExpected, [], []);
return false;
}
if (_scanner.getToken() !== SyntaxKind.EOF) {
handleError(ParseErrorCode.EndOfFileExpected, [], []);
}
return true;
}
/**
* Takes JSON with JavaScript-style comments and remove
* them. Optionally replaces every none-newline character
* of comments with a replaceCharacter
*/
export function stripComments(text: string, replaceCh?: string): string {
let _scanner = createScanner(text),
parts: string[] = [],
kind: SyntaxKind,
offset = 0,
pos: number;
do {
pos = _scanner.getPosition();
kind = _scanner.scan();
switch (kind) {
case SyntaxKind.LineCommentTrivia:
case SyntaxKind.BlockCommentTrivia:
case SyntaxKind.EOF:
if (offset !== pos) {
parts.push(text.substring(offset, pos));
}
if (replaceCh !== undefined) {
parts.push(_scanner.getTokenValue().replace(/[^\r\n]/g, replaceCh));
}
offset = _scanner.getPosition();
break;
}
} while (kind !== SyntaxKind.EOF);
return parts.join('');
}
export function getNodeType(value: any): NodeType {
switch (typeof value) {
case 'boolean': return 'boolean';
case 'number': return 'number';
case 'string': return 'string';
case 'object': {
if (!value) {
return 'null';
} else if (Array.isArray(value)) {
return 'array';
}
return 'object';
}
default: return 'null';
}
}