std/yaml/_loader_state.ts

1726 lines
45 KiB
TypeScript

// Ported from js-yaml v3.13.1:
// https://github.com/nodeca/js-yaml/commit/665aadda42349dcae869f12040d9b10ef18d12da
// Copyright 2011-2015 by Vitaly Puzrin. All rights reserved. MIT license.
// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
import {
AMPERSAND,
ASTERISK,
BACKSLASH,
CARRIAGE_RETURN,
COLON,
COMMA,
COMMERCIAL_AT,
DOT,
DOUBLE_QUOTE,
EXCLAMATION,
GRAVE_ACCENT,
GREATER_THAN,
isEOL,
isFlowIndicator,
isWhiteSpace,
isWhiteSpaceOrEOL,
LEFT_CURLY_BRACKET,
LEFT_SQUARE_BRACKET,
LINE_FEED,
MINUS,
PERCENT,
PLUS,
QUESTION,
RIGHT_CURLY_BRACKET,
RIGHT_SQUARE_BRACKET,
SHARP,
SINGLE_QUOTE,
SMALLER_THAN,
SPACE,
VERTICAL_LINE,
} from "./_chars.ts";
import { DEFAULT_SCHEMA, type Schema, type TypeMap } from "./_schema.ts";
import type { KindType, Type } from "./_type.ts";
import { isObject, isPlainObject } from "./_utils.ts";
const CONTEXT_FLOW_IN = 1;
const CONTEXT_FLOW_OUT = 2;
const CONTEXT_BLOCK_IN = 3;
const CONTEXT_BLOCK_OUT = 4;
const CHOMPING_CLIP = 1;
const CHOMPING_STRIP = 2;
const CHOMPING_KEEP = 3;
const PATTERN_NON_PRINTABLE =
// deno-lint-ignore no-control-regex
/[\x00-\x08\x0B\x0C\x0E-\x1F\x7F-\x84\x86-\x9F\uFFFE\uFFFF]|[\uD800-\uDBFF](?![\uDC00-\uDFFF])|(?:[^\uD800-\uDBFF]|^)[\uDC00-\uDFFF]/;
const PATTERN_NON_ASCII_LINE_BREAKS = /[\x85\u2028\u2029]/;
const PATTERN_FLOW_INDICATORS = /[,\[\]\{\}]/;
const PATTERN_TAG_HANDLE = /^(?:!|!!|![a-z\-]+!)$/i;
const PATTERN_TAG_URI =
/^(?:!|[^,\[\]\{\}])(?:%[0-9a-f]{2}|[0-9a-z\-#;\/\?:@&=\+\$,_\.!~\*'\(\)\[\]])*$/i;
export interface LoaderStateOptions {
/** specifies a schema to use. */
schema?: Schema;
/** compatibility with JSON.parse behaviour. */
allowDuplicateKeys?: boolean;
/** function to call on warning messages. */
onWarning?(error: Error): void;
}
const ESCAPED_HEX_LENGTHS = new Map<number, number>([
[0x78, 2], // x
[0x75, 4], // u
[0x55, 8], // U
]);
const SIMPLE_ESCAPE_SEQUENCES = new Map<number, string>([
[0x30, "\x00"], // 0
[0x61, "\x07"], // a
[0x62, "\x08"], // b
[0x74, "\x09"], // t
[0x09, "\x09"], // Tab
[0x6e, "\x0A"], // n
[0x76, "\x0B"], // v
[0x66, "\x0C"], // f
[0x72, "\x0D"], // r
[0x65, "\x1B"], // e
[0x20, " "], // Space
[0x22, '"'], // "
[0x2f, "/"], // /
[0x5c, "\\"], // \
[0x4e, "\x85"], // N
[0x5f, "\xA0"], // _
[0x4c, "\u2028"], // L
[0x50, "\u2029"], // P
]);
/**
* Converts a hexadecimal character code to its decimal value.
*/
function hexCharCodeToNumber(charCode: number) {
// Check if the character code is in the range for '0' to '9'
if (0x30 <= charCode && charCode <= 0x39) return charCode - 0x30; // Convert '0'-'9' to 0-9
// Normalize the character code to lowercase if it's a letter
const lc = charCode | 0x20;
// Check if the character code is in the range for 'a' to 'f'
if (0x61 <= lc && lc <= 0x66) return lc - 0x61 + 10; // Convert 'a'-'f' to 10-15
return -1;
}
/**
* Converts a decimal character code to its decimal value.
*/
function decimalCharCodeToNumber(charCode: number): number {
// Check if the character code is in the range for '0' to '9'
if (0x30 <= charCode && charCode <= 0x39) return charCode - 0x30; // Convert '0'-'9' to 0-9
return -1;
}
/**
* Converts a Unicode code point to a string.
*/
function codepointToChar(codepoint: number): string {
// Check if the code point is within the Basic Multilingual Plane (BMP)
if (codepoint <= 0xffff) return String.fromCharCode(codepoint); // Convert BMP code point to character
// Encode UTF-16 surrogate pair for code points beyond BMP
// Reference: https://en.wikipedia.org/wiki/UTF-16#Code_points_U.2B010000_to_U.2B10FFFF
return String.fromCharCode(
((codepoint - 0x010000) >> 10) + 0xd800, // High surrogate
((codepoint - 0x010000) & 0x03ff) + 0xdc00, // Low surrogate
);
}
const INDENT = 4;
const MAX_LENGTH = 75;
const DELIMITERS = "\x00\r\n\x85\u2028\u2029";
function getSnippet(buffer: string, position: number): string | null {
if (!buffer) return null;
let start = position;
let end = position;
let head = "";
let tail = "";
while (start > 0 && !DELIMITERS.includes(buffer.charAt(start - 1))) {
start--;
if (position - start > MAX_LENGTH / 2 - 1) {
head = " ... ";
start += 5;
break;
}
}
while (end < buffer.length && !DELIMITERS.includes(buffer.charAt(end))) {
end++;
if (end - position > MAX_LENGTH / 2 - 1) {
tail = " ... ";
end -= 5;
break;
}
}
const snippet = buffer.slice(start, end);
const indent = " ".repeat(INDENT);
const caretIndent = " ".repeat(INDENT + position - start + head.length);
return `${indent + head + snippet + tail}\n${caretIndent}^`;
}
function markToString(
buffer: string,
position: number,
line: number,
column: number,
): string {
let where = `at line ${line + 1}, column ${column + 1}`;
const snippet = getSnippet(buffer, position);
if (snippet) where += `:\n${snippet}`;
return where;
}
export class LoaderState {
input: string;
length: number;
lineIndent = 0;
lineStart = 0;
position = 0;
line = 0;
onWarning: ((error: Error) => void) | undefined;
allowDuplicateKeys: boolean;
implicitTypes: Type<"scalar">[];
typeMap: TypeMap;
version: string | null;
checkLineBreaks = false;
tagMap = new Map();
anchorMap = new Map();
tag: string | null | undefined;
anchor: string | null | undefined;
kind: string | null | undefined;
result: unknown[] | Record<string, unknown> | string | null = "";
constructor(
input: string,
{
schema = DEFAULT_SCHEMA,
onWarning,
allowDuplicateKeys = false,
}: LoaderStateOptions,
) {
this.input = input;
this.onWarning = onWarning;
this.allowDuplicateKeys = allowDuplicateKeys;
this.implicitTypes = schema.implicitTypes;
this.typeMap = schema.typeMap;
this.length = input.length;
this.version = null;
this.readIndent();
}
readIndent() {
let char = this.peek();
while (char === SPACE) {
this.lineIndent += 1;
char = this.next();
}
}
peek(offset = 0) {
return this.input.charCodeAt(this.position + offset);
}
next() {
this.position += 1;
return this.peek();
}
#createError(message: string): SyntaxError {
const mark = markToString(
this.input,
this.position,
this.line,
this.position - this.lineStart,
);
return new SyntaxError(`${message} ${mark}`);
}
throwError(message: string): never {
throw this.#createError(message);
}
dispatchWarning(message: string) {
const error = this.#createError(message);
this.onWarning?.(error);
}
yamlDirectiveHandler(...args: string[]) {
if (this.version !== null) {
return this.throwError(
"Cannot handle YAML directive: duplication of %YAML directive",
);
}
if (args.length !== 1) {
return this.throwError(
"Cannot handle YAML directive: YAML directive accepts exactly one argument",
);
}
const match = /^([0-9]+)\.([0-9]+)$/.exec(args[0]!);
if (match === null) {
return this.throwError(
"Cannot handle YAML directive: ill-formed argument",
);
}
const major = parseInt(match[1]!, 10);
const minor = parseInt(match[2]!, 10);
if (major !== 1) {
return this.throwError(
"Cannot handle YAML directive: unacceptable YAML version",
);
}
this.version = args[0] ?? null;
this.checkLineBreaks = minor < 2;
if (minor !== 1 && minor !== 2) {
return this.dispatchWarning(
"Cannot handle YAML directive: unsupported YAML version",
);
}
}
tagDirectiveHandler(...args: string[]) {
if (args.length !== 2) {
return this.throwError(
`Cannot handle tag directive: directive accepts exactly two arguments, received ${args.length}`,
);
}
const handle = args[0]!;
const prefix = args[1]!;
if (!PATTERN_TAG_HANDLE.test(handle)) {
return this.throwError(
`Cannot handle tag directive: ill-formed handle (first argument) in "${handle}"`,
);
}
if (this.tagMap.has(handle)) {
return this.throwError(
`Cannot handle tag directive: previously declared suffix for "${handle}" tag handle`,
);
}
if (!PATTERN_TAG_URI.test(prefix)) {
return this.throwError(
"Cannot handle tag directive: ill-formed tag prefix (second argument) of the TAG directive",
);
}
this.tagMap.set(handle, prefix);
}
captureSegment(start: number, end: number, checkJson: boolean) {
let result: string;
if (start < end) {
result = this.input.slice(start, end);
if (checkJson) {
for (
let position = 0;
position < result.length;
position++
) {
const character = result.charCodeAt(position);
if (
!(character === 0x09 ||
(0x20 <= character && character <= 0x10ffff))
) {
return this.throwError(
`Expected valid JSON character: received "${character}"`,
);
}
}
} else if (PATTERN_NON_PRINTABLE.test(result)) {
return this.throwError("Stream contains non-printable characters");
}
this.result += result;
}
}
readBlockSequence(nodeIndent: number): boolean {
let line: number;
let following: number;
let detected = false;
let ch: number;
const tag = this.tag;
const anchor = this.anchor;
const result: unknown[] = [];
if (this.anchor !== null && typeof this.anchor !== "undefined") {
this.anchorMap.set(this.anchor, result);
}
ch = this.peek();
while (ch !== 0) {
if (ch !== MINUS) {
break;
}
following = this.peek(1);
if (!isWhiteSpaceOrEOL(following)) {
break;
}
detected = true;
this.position++;
if (this.skipSeparationSpace(true, -1)) {
if (this.lineIndent <= nodeIndent) {
result.push(null);
ch = this.peek();
continue;
}
}
line = this.line;
this.composeNode(nodeIndent, CONTEXT_BLOCK_IN, false, true);
result.push(this.result);
this.skipSeparationSpace(true, -1);
ch = this.peek();
if ((this.line === line || this.lineIndent > nodeIndent) && ch !== 0) {
return this.throwError(
"Cannot read block sequence: bad indentation of a sequence entry",
);
} else if (this.lineIndent < nodeIndent) {
break;
}
}
if (detected) {
this.tag = tag;
this.anchor = anchor;
this.kind = "sequence";
this.result = result;
return true;
}
return false;
}
mergeMappings(
destination: Record<string, unknown>,
source: Record<string, unknown>,
overridableKeys: Set<string>,
) {
if (!isObject(source)) {
return this.throwError(
"Cannot merge mappings: the provided source object is unacceptable",
);
}
for (const [key, value] of Object.entries(source)) {
if (Object.hasOwn(destination, key)) continue;
Object.defineProperty(destination, key, {
value,
writable: true,
enumerable: true,
configurable: true,
});
overridableKeys.add(key);
}
}
storeMappingPair(
result: Record<string, unknown>,
overridableKeys: Set<string>,
keyTag: string | null,
keyNode: Record<PropertyKey, unknown> | unknown[] | string | null,
valueNode: unknown,
startLine?: number,
startPos?: number,
): Record<string, unknown> {
// The output is a plain object here, so keys can only be strings.
// We need to convert keyNode to a string, but doing so can hang the process
// (deeply nested arrays that explode exponentially using aliases).
if (Array.isArray(keyNode)) {
keyNode = Array.prototype.slice.call(keyNode);
for (let index = 0; index < keyNode.length; index++) {
if (Array.isArray(keyNode[index])) {
return this.throwError(
"Cannot store mapping pair: nested arrays are not supported inside keys",
);
}
if (typeof keyNode === "object" && isPlainObject(keyNode[index])) {
keyNode[index] = "[object Object]";
}
}
}
// Avoid code execution in load() via toString property
// (still use its own toString for arrays, timestamps,
// and whatever user schema extensions happen to have @@toStringTag)
if (typeof keyNode === "object" && isPlainObject(keyNode)) {
keyNode = "[object Object]";
}
keyNode = String(keyNode);
if (keyTag === "tag:yaml.org,2002:merge") {
if (Array.isArray(valueNode)) {
for (
let index = 0;
index < valueNode.length;
index++
) {
this.mergeMappings(result, valueNode[index], overridableKeys);
}
} else {
this.mergeMappings(
result,
valueNode as Record<string, unknown>,
overridableKeys,
);
}
} else {
if (
!this.allowDuplicateKeys &&
!overridableKeys.has(keyNode) &&
Object.hasOwn(result, keyNode)
) {
this.line = startLine || this.line;
this.position = startPos || this.position;
return this.throwError("Cannot store mapping pair: duplicated key");
}
Object.defineProperty(result, keyNode, {
value: valueNode,
writable: true,
enumerable: true,
configurable: true,
});
overridableKeys.delete(keyNode);
}
return result;
}
readLineBreak() {
const ch = this.peek();
if (ch === LINE_FEED) {
this.position++;
} else if (ch === CARRIAGE_RETURN) {
this.position++;
if (this.peek() === LINE_FEED) {
this.position++;
}
} else {
return this.throwError("Cannot read line: line break not found");
}
this.line += 1;
this.lineStart = this.position;
}
skipSeparationSpace(allowComments: boolean, checkIndent: number): number {
let lineBreaks = 0;
let ch = this.peek();
while (ch !== 0) {
while (isWhiteSpace(ch)) {
ch = this.next();
}
if (allowComments && ch === SHARP) {
do {
ch = this.next();
} while (ch !== LINE_FEED && ch !== CARRIAGE_RETURN && ch !== 0);
}
if (isEOL(ch)) {
this.readLineBreak();
ch = this.peek();
lineBreaks++;
this.lineIndent = 0;
this.readIndent();
ch = this.peek();
} else {
break;
}
}
if (
checkIndent !== -1 &&
lineBreaks !== 0 &&
this.lineIndent < checkIndent
) {
this.dispatchWarning("deficient indentation");
}
return lineBreaks;
}
testDocumentSeparator(): boolean {
let ch = this.peek();
// Condition this.position === this.lineStart is tested
// in parent on each call, for efficiency. No needs to test here again.
if (
(ch === MINUS || ch === DOT) &&
ch === this.peek(1) &&
ch === this.peek(2)
) {
ch = this.peek(3);
if (ch === 0 || isWhiteSpaceOrEOL(ch)) {
return true;
}
}
return false;
}
writeFoldedLines(count: number) {
if (count === 1) {
this.result += " ";
} else if (count > 1) {
this.result += "\n".repeat(count - 1);
}
}
readPlainScalar(nodeIndent: number, withinFlowCollection: boolean): boolean {
const kind = this.kind;
const result = this.result;
let ch = this.peek();
if (
isWhiteSpaceOrEOL(ch) ||
isFlowIndicator(ch) ||
ch === SHARP ||
ch === AMPERSAND ||
ch === ASTERISK ||
ch === EXCLAMATION ||
ch === VERTICAL_LINE ||
ch === GREATER_THAN ||
ch === SINGLE_QUOTE ||
ch === DOUBLE_QUOTE ||
ch === PERCENT ||
ch === COMMERCIAL_AT ||
ch === GRAVE_ACCENT
) {
return false;
}
let following: number;
if (ch === QUESTION || ch === MINUS) {
following = this.peek(1);
if (
isWhiteSpaceOrEOL(following) ||
(withinFlowCollection && isFlowIndicator(following))
) {
return false;
}
}
this.kind = "scalar";
this.result = "";
let captureEnd = this.position;
let captureStart = this.position;
let hasPendingContent = false;
let line = 0;
while (ch !== 0) {
if (ch === COLON) {
following = this.peek(1);
if (
isWhiteSpaceOrEOL(following) ||
(withinFlowCollection && isFlowIndicator(following))
) {
break;
}
} else if (ch === SHARP) {
const preceding = this.peek(-1);
if (isWhiteSpaceOrEOL(preceding)) {
break;
}
} else if (
(this.position === this.lineStart && this.testDocumentSeparator()) ||
(withinFlowCollection && isFlowIndicator(ch))
) {
break;
} else if (isEOL(ch)) {
line = this.line;
const lineStart = this.lineStart;
const lineIndent = this.lineIndent;
this.skipSeparationSpace(false, -1);
if (this.lineIndent >= nodeIndent) {
hasPendingContent = true;
ch = this.peek();
continue;
} else {
this.position = captureEnd;
this.line = line;
this.lineStart = lineStart;
this.lineIndent = lineIndent;
break;
}
}
if (hasPendingContent) {
this.captureSegment(captureStart, captureEnd, false);
this.writeFoldedLines(this.line - line);
captureStart = captureEnd = this.position;
hasPendingContent = false;
}
if (!isWhiteSpace(ch)) {
captureEnd = this.position + 1;
}
ch = this.next();
}
this.captureSegment(captureStart, captureEnd, false);
if (this.result) {
return true;
}
this.kind = kind;
this.result = result;
return false;
}
readSingleQuotedScalar(nodeIndent: number): boolean {
let ch;
let captureStart;
let captureEnd;
ch = this.peek();
if (ch !== SINGLE_QUOTE) {
return false;
}
this.kind = "scalar";
this.result = "";
this.position++;
captureStart = captureEnd = this.position;
while ((ch = this.peek()) !== 0) {
if (ch === SINGLE_QUOTE) {
this.captureSegment(captureStart, this.position, true);
ch = this.next();
if (ch === SINGLE_QUOTE) {
captureStart = this.position;
this.position++;
captureEnd = this.position;
} else {
return true;
}
} else if (isEOL(ch)) {
this.captureSegment(captureStart, captureEnd, true);
this.writeFoldedLines(this.skipSeparationSpace(false, nodeIndent));
captureStart = captureEnd = this.position;
} else if (
this.position === this.lineStart &&
this.testDocumentSeparator()
) {
return this.throwError(
"Unexpected end of the document within a single quoted scalar",
);
} else {
this.position++;
captureEnd = this.position;
}
}
return this.throwError(
"Unexpected end of the stream within a single quoted scalar",
);
}
readDoubleQuotedScalar(nodeIndent: number): boolean {
let ch = this.peek();
if (ch !== DOUBLE_QUOTE) {
return false;
}
this.kind = "scalar";
this.result = "";
this.position++;
let captureEnd = this.position;
let captureStart = this.position;
let tmp: number;
while ((ch = this.peek()) !== 0) {
if (ch === DOUBLE_QUOTE) {
this.captureSegment(captureStart, this.position, true);
this.position++;
return true;
}
if (ch === BACKSLASH) {
this.captureSegment(captureStart, this.position, true);
ch = this.next();
if (isEOL(ch)) {
this.skipSeparationSpace(false, nodeIndent);
} else if (ch < 256 && SIMPLE_ESCAPE_SEQUENCES.has(ch)) {
this.result += SIMPLE_ESCAPE_SEQUENCES.get(ch);
this.position++;
} else if ((tmp = ESCAPED_HEX_LENGTHS.get(ch) ?? 0) > 0) {
let hexLength = tmp;
let hexResult = 0;
for (; hexLength > 0; hexLength--) {
ch = this.next();
if ((tmp = hexCharCodeToNumber(ch)) >= 0) {
hexResult = (hexResult << 4) + tmp;
} else {
return this.throwError(
"Cannot read double quoted scalar: expected hexadecimal character",
);
}
}
this.result += codepointToChar(hexResult);
this.position++;
} else {
return this.throwError(
"Cannot read double quoted scalar: unknown escape sequence",
);
}
captureStart = captureEnd = this.position;
} else if (isEOL(ch)) {
this.captureSegment(captureStart, captureEnd, true);
this.writeFoldedLines(this.skipSeparationSpace(false, nodeIndent));
captureStart = captureEnd = this.position;
} else if (
this.position === this.lineStart &&
this.testDocumentSeparator()
) {
return this.throwError(
"Unexpected end of the document within a double quoted scalar",
);
} else {
this.position++;
captureEnd = this.position;
}
}
return this.throwError(
"Unexpected end of the stream within a double quoted scalar",
);
}
readFlowCollection(nodeIndent: number): boolean {
let ch = this.peek();
let terminator: number;
let isMapping = true;
let result = {};
if (ch === LEFT_SQUARE_BRACKET) {
terminator = RIGHT_SQUARE_BRACKET;
isMapping = false;
result = [];
} else if (ch === LEFT_CURLY_BRACKET) {
terminator = RIGHT_CURLY_BRACKET;
} else {
return false;
}
if (this.anchor !== null && typeof this.anchor !== "undefined") {
this.anchorMap.set(this.anchor, result);
}
ch = this.next();
const tag = this.tag;
const anchor = this.anchor;
let readNext = true;
let valueNode = null;
let keyNode = null;
let keyTag: string | null = null;
let isExplicitPair = false;
let isPair = false;
let following = 0;
let line = 0;
const overridableKeys = new Set<string>();
while (ch !== 0) {
this.skipSeparationSpace(true, nodeIndent);
ch = this.peek();
if (ch === terminator) {
this.position++;
this.tag = tag;
this.anchor = anchor;
this.kind = isMapping ? "mapping" : "sequence";
this.result = result;
return true;
}
if (!readNext) {
return this.throwError(
"Cannot read flow collection: missing comma between flow collection entries",
);
}
keyTag = keyNode = valueNode = null;
isPair = isExplicitPair = false;
if (ch === QUESTION) {
following = this.peek(1);
if (isWhiteSpaceOrEOL(following)) {
isPair = isExplicitPair = true;
this.position++;
this.skipSeparationSpace(true, nodeIndent);
}
}
line = this.line;
this.composeNode(nodeIndent, CONTEXT_FLOW_IN, false, true);
keyTag = this.tag || null;
keyNode = this.result;
this.skipSeparationSpace(true, nodeIndent);
ch = this.peek();
if ((isExplicitPair || this.line === line) && ch === COLON) {
isPair = true;
ch = this.next();
this.skipSeparationSpace(true, nodeIndent);
this.composeNode(nodeIndent, CONTEXT_FLOW_IN, false, true);
valueNode = this.result;
}
if (isMapping) {
this.storeMappingPair(
result as Record<string, unknown>,
overridableKeys,
keyTag,
keyNode,
valueNode,
);
} else if (isPair) {
(result as Record<string, unknown>[]).push(
this.storeMappingPair(
{},
overridableKeys,
keyTag,
keyNode,
valueNode,
),
);
} else {
(result as unknown[]).push(keyNode);
}
this.skipSeparationSpace(true, nodeIndent);
ch = this.peek();
if (ch === COMMA) {
readNext = true;
ch = this.next();
} else {
readNext = false;
}
}
return this.throwError(
"Cannot read flow collection: unexpected end of the stream within a flow collection",
);
}
// Handles block scaler styles: e.g. '|', '>', '|-' and '>-'.
// https://yaml.org/spec/1.2.2/#81-block-scalar-styles
readBlockScalar(nodeIndent: number): boolean {
let chomping = CHOMPING_CLIP;
let didReadContent = false;
let detectedIndent = false;
let textIndent = nodeIndent;
let emptyLines = 0;
let atMoreIndented = false;
let ch = this.peek();
let folding = false;
if (ch === VERTICAL_LINE) {
folding = false;
} else if (ch === GREATER_THAN) {
folding = true;
} else {
return false;
}
this.kind = "scalar";
this.result = "";
let tmp = 0;
while (ch !== 0) {
ch = this.next();
if (ch === PLUS || ch === MINUS) {
if (CHOMPING_CLIP === chomping) {
chomping = ch === PLUS ? CHOMPING_KEEP : CHOMPING_STRIP;
} else {
return this.throwError(
"Cannot read block: chomping mode identifier repeated",
);
}
} else if ((tmp = decimalCharCodeToNumber(ch)) >= 0) {
if (tmp === 0) {
return this.throwError(
"Cannot read block: indentation width must be greater than 0",
);
} else if (!detectedIndent) {
textIndent = nodeIndent + tmp - 1;
detectedIndent = true;
} else {
return this.throwError(
"Cannot read block: indentation width identifier repeated",
);
}
} else {
break;
}
}
if (isWhiteSpace(ch)) {
do {
ch = this.next();
} while (isWhiteSpace(ch));
if (ch === SHARP) {
do {
ch = this.next();
} while (!isEOL(ch) && ch !== 0);
}
}
while (ch !== 0) {
this.readLineBreak();
this.lineIndent = 0;
ch = this.peek();
while (
(!detectedIndent || this.lineIndent < textIndent) &&
ch === SPACE
) {
this.lineIndent++;
ch = this.next();
}
if (!detectedIndent && this.lineIndent > textIndent) {
textIndent = this.lineIndent;
}
if (isEOL(ch)) {
emptyLines++;
continue;
}
// End of the scalar.
if (this.lineIndent < textIndent) {
// Perform the chomping.
if (chomping === CHOMPING_KEEP) {
this.result += "\n".repeat(
didReadContent ? 1 + emptyLines : emptyLines,
);
} else if (chomping === CHOMPING_CLIP) {
if (didReadContent) {
// i.e. only if the scalar is not empty.
this.result += "\n";
}
}
// Break this `while` cycle and go to the function's epilogue.
break;
}
// Folded style: use fancy rules to handle line breaks.
if (folding) {
// Lines starting with white space characters (more-indented lines) are not folded.
if (isWhiteSpace(ch)) {
atMoreIndented = true;
// except for the first content line (cf. Example 8.1)
this.result += "\n".repeat(
didReadContent ? 1 + emptyLines : emptyLines,
);
// End of more-indented block.
} else if (atMoreIndented) {
atMoreIndented = false;
this.result += "\n".repeat(emptyLines + 1);
// Just one line break - perceive as the same line.
} else if (emptyLines === 0) {
if (didReadContent) {
// i.e. only if we have already read some scalar content.
this.result += " ";
}
// Several line breaks - perceive as different lines.
} else {
this.result += "\n".repeat(emptyLines);
}
// Literal style: just add exact number of line breaks between content lines.
} else {
// Keep all line breaks except the header line break.
this.result += "\n".repeat(
didReadContent ? 1 + emptyLines : emptyLines,
);
}
didReadContent = true;
detectedIndent = true;
emptyLines = 0;
const captureStart = this.position;
while (!isEOL(ch) && ch !== 0) {
ch = this.next();
}
this.captureSegment(captureStart, this.position, false);
}
return true;
}
readBlockMapping(nodeIndent: number, flowIndent: number): boolean {
const tag = this.tag;
const anchor = this.anchor;
const result = {};
const overridableKeys = new Set<string>();
let following: number;
let allowCompact = false;
let line: number;
let pos: number;
let keyTag = null;
let keyNode = null;
let valueNode = null;
let atExplicitKey = false;
let detected = false;
let ch: number;
if (this.anchor !== null && typeof this.anchor !== "undefined") {
this.anchorMap.set(this.anchor, result);
}
ch = this.peek();
while (ch !== 0) {
following = this.peek(1);
line = this.line; // Save the current line.
pos = this.position;
//
// Explicit notation case. There are two separate blocks:
// first for the key (denoted by "?") and second for the value (denoted by ":")
//
if ((ch === QUESTION || ch === COLON) && isWhiteSpaceOrEOL(following)) {
if (ch === QUESTION) {
if (atExplicitKey) {
this.storeMappingPair(
result,
overridableKeys,
keyTag as string,
keyNode,
null,
);
keyTag = keyNode = valueNode = null;
}
detected = true;
atExplicitKey = true;
allowCompact = true;
} else if (atExplicitKey) {
// i.e. 0x3A/* : */ === character after the explicit key.
atExplicitKey = false;
allowCompact = true;
} else {
return this.throwError(
"Cannot read block as explicit mapping pair is incomplete: a key node is missed or followed by a non-tabulated empty line",
);
}
this.position += 1;
ch = following;
//
// Implicit notation case. Flow-style node as the key first, then ":", and the value.
//
} else if (this.composeNode(flowIndent, CONTEXT_FLOW_OUT, false, true)) {
if (this.line === line) {
ch = this.peek();
while (isWhiteSpace(ch)) {
ch = this.next();
}
if (ch === COLON) {
ch = this.next();
if (!isWhiteSpaceOrEOL(ch)) {
return this.throwError(
"Cannot read block: a whitespace character is expected after the key-value separator within a block mapping",
);
}
if (atExplicitKey) {
this.storeMappingPair(
result,
overridableKeys,
keyTag as string,
keyNode,
null,
);
keyTag = keyNode = valueNode = null;
}
detected = true;
atExplicitKey = false;
allowCompact = false;
keyTag = this.tag;
keyNode = this.result;
} else if (detected) {
return this.throwError(
"Cannot read an implicit mapping pair: missing colon",
);
} else {
this.tag = tag;
this.anchor = anchor;
return true; // Keep the result of `composeNode`.
}
} else if (detected) {
return this.throwError(
"Cannot read a block mapping entry: a multiline key may not be an implicit key",
);
} else {
this.tag = tag;
this.anchor = anchor;
return true; // Keep the result of `composeNode`.
}
} else {
break; // Reading is done. Go to the epilogue.
}
//
// Common reading code for both explicit and implicit notations.
//
if (this.line === line || this.lineIndent > nodeIndent) {
if (
this.composeNode(nodeIndent, CONTEXT_BLOCK_OUT, true, allowCompact)
) {
if (atExplicitKey) {
keyNode = this.result;
} else {
valueNode = this.result;
}
}
if (!atExplicitKey) {
this.storeMappingPair(
result,
overridableKeys,
keyTag as string,
keyNode,
valueNode,
line,
pos,
);
keyTag = keyNode = valueNode = null;
}
this.skipSeparationSpace(true, -1);
ch = this.peek();
}
if (this.lineIndent > nodeIndent && ch !== 0) {
return this.throwError(
"Cannot read block: bad indentation of a mapping entry",
);
} else if (this.lineIndent < nodeIndent) {
break;
}
}
//
// Epilogue.
//
// Special case: last mapping's node contains only the key in explicit notation.
if (atExplicitKey) {
this.storeMappingPair(
result,
overridableKeys,
keyTag as string,
keyNode,
null,
);
}
// Expose the resulting mapping.
if (detected) {
this.tag = tag;
this.anchor = anchor;
this.kind = "mapping";
this.result = result;
}
return detected;
}
readTagProperty(): boolean {
let position: number;
let isVerbatim = false;
let isNamed = false;
let tagHandle = "";
let tagName: string;
let ch: number;
ch = this.peek();
if (ch !== EXCLAMATION) return false;
if (this.tag !== null) {
return this.throwError(
"Cannot read tag property: duplication of a tag property",
);
}
ch = this.next();
if (ch === SMALLER_THAN) {
isVerbatim = true;
ch = this.next();
} else if (ch === EXCLAMATION) {
isNamed = true;
tagHandle = "!!";
ch = this.next();
} else {
tagHandle = "!";
}
position = this.position;
if (isVerbatim) {
do {
ch = this.next();
} while (ch !== 0 && ch !== GREATER_THAN);
if (this.position < this.length) {
tagName = this.input.slice(position, this.position);
ch = this.next();
} else {
return this.throwError(
"Cannot read tag property: unexpected end of stream",
);
}
} else {
while (ch !== 0 && !isWhiteSpaceOrEOL(ch)) {
if (ch === EXCLAMATION) {
if (!isNamed) {
tagHandle = this.input.slice(position - 1, this.position + 1);
if (!PATTERN_TAG_HANDLE.test(tagHandle)) {
return this.throwError(
"Cannot read tag property: named tag handle contains invalid characters",
);
}
isNamed = true;
position = this.position + 1;
} else {
return this.throwError(
"Cannot read tag property: tag suffix cannot contain an exclamation mark",
);
}
}
ch = this.next();
}
tagName = this.input.slice(position, this.position);
if (PATTERN_FLOW_INDICATORS.test(tagName)) {
return this.throwError(
"Cannot read tag property: tag suffix cannot contain flow indicator characters",
);
}
}
if (tagName && !PATTERN_TAG_URI.test(tagName)) {
return this.throwError(
`Cannot read tag property: invalid characters in tag name "${tagName}"`,
);
}
if (isVerbatim) {
this.tag = tagName;
} else if (this.tagMap.has(tagHandle)) {
this.tag = this.tagMap.get(tagHandle) + tagName;
} else if (tagHandle === "!") {
this.tag = `!${tagName}`;
} else if (tagHandle === "!!") {
this.tag = `tag:yaml.org,2002:${tagName}`;
} else {
return this.throwError(
`Cannot read tag property: undeclared tag handle "${tagHandle}"`,
);
}
return true;
}
readAnchorProperty(): boolean {
let ch = this.peek();
if (ch !== AMPERSAND) return false;
if (this.anchor !== null) {
return this.throwError(
"Cannot read anchor property: duplicate anchor property",
);
}
ch = this.next();
const position = this.position;
while (ch !== 0 && !isWhiteSpaceOrEOL(ch) && !isFlowIndicator(ch)) {
ch = this.next();
}
if (this.position === position) {
return this.throwError(
"Cannot read anchor property: name of an anchor node must contain at least one character",
);
}
this.anchor = this.input.slice(position, this.position);
return true;
}
readAlias(): boolean {
if (this.peek() !== ASTERISK) return false;
let ch = this.next();
const position = this.position;
while (ch !== 0 && !isWhiteSpaceOrEOL(ch) && !isFlowIndicator(ch)) {
ch = this.next();
}
if (this.position === position) {
return this.throwError(
"Cannot read alias: alias name must contain at least one character",
);
}
const alias = this.input.slice(position, this.position);
if (!this.anchorMap.has(alias)) {
return this.throwError(
`Cannot read alias: unidentified alias "${alias}"`,
);
}
this.result = this.anchorMap.get(alias);
this.skipSeparationSpace(true, -1);
return true;
}
composeNode(
parentIndent: number,
nodeContext: number,
allowToSeek: boolean,
allowCompact: boolean,
): boolean {
let allowBlockScalars: boolean;
let allowBlockCollections: boolean;
let indentStatus = 1; // 1: this>parent, 0: this=parent, -1: this<parent
let atNewLine = false;
let hasContent = false;
let type: Type<KindType>;
let flowIndent: number;
let blockIndent: number;
this.tag = null;
this.anchor = null;
this.kind = null;
this.result = null;
const allowBlockStyles = (allowBlockScalars =
allowBlockCollections =
CONTEXT_BLOCK_OUT === nodeContext || CONTEXT_BLOCK_IN === nodeContext);
if (allowToSeek) {
if (this.skipSeparationSpace(true, -1)) {
atNewLine = true;
if (this.lineIndent > parentIndent) {
indentStatus = 1;
} else if (this.lineIndent === parentIndent) {
indentStatus = 0;
} else if (this.lineIndent < parentIndent) {
indentStatus = -1;
}
}
}
if (indentStatus === 1) {
while (this.readTagProperty() || this.readAnchorProperty()) {
if (this.skipSeparationSpace(true, -1)) {
atNewLine = true;
allowBlockCollections = allowBlockStyles;
if (this.lineIndent > parentIndent) {
indentStatus = 1;
} else if (this.lineIndent === parentIndent) {
indentStatus = 0;
} else if (this.lineIndent < parentIndent) {
indentStatus = -1;
}
} else {
allowBlockCollections = false;
}
}
}
if (allowBlockCollections) {
allowBlockCollections = atNewLine || allowCompact;
}
if (indentStatus === 1 || CONTEXT_BLOCK_OUT === nodeContext) {
const cond = CONTEXT_FLOW_IN === nodeContext ||
CONTEXT_FLOW_OUT === nodeContext;
flowIndent = cond ? parentIndent : parentIndent + 1;
blockIndent = this.position - this.lineStart;
if (indentStatus === 1) {
if (
(allowBlockCollections &&
(this.readBlockSequence(blockIndent) ||
this.readBlockMapping(blockIndent, flowIndent))) ||
this.readFlowCollection(flowIndent)
) {
hasContent = true;
} else {
if (
(allowBlockScalars && this.readBlockScalar(flowIndent)) ||
this.readSingleQuotedScalar(flowIndent) ||
this.readDoubleQuotedScalar(flowIndent)
) {
hasContent = true;
} else if (this.readAlias()) {
hasContent = true;
if (this.tag !== null || this.anchor !== null) {
return this.throwError(
"Cannot compose node: alias node should not have any properties",
);
}
} else if (
this.readPlainScalar(flowIndent, CONTEXT_FLOW_IN === nodeContext)
) {
hasContent = true;
if (this.tag === null) {
this.tag = "?";
}
}
if (this.anchor !== null) {
this.anchorMap.set(this.anchor, this.result);
}
}
} else if (indentStatus === 0) {
// Special case: block sequences are allowed to have same indentation level as the parent.
// http://www.yaml.org/spec/1.2/spec.html#id2799784
hasContent = allowBlockCollections &&
this.readBlockSequence(blockIndent);
}
}
if (this.tag !== null && this.tag !== "!") {
if (this.tag === "?") {
for (
let typeIndex = 0;
typeIndex < this.implicitTypes.length;
typeIndex++
) {
type = this.implicitTypes[typeIndex]!;
// Implicit resolving is not allowed for non-scalar types, and '?'
// non-specific tag is only assigned to plain scalars. So, it isn't
// needed to check for 'kind' conformity.
if (type.resolve(this.result)) {
// `state.result` updated in resolver if matched
this.result = type.construct(this.result);
this.tag = type.tag;
if (this.anchor !== null) {
this.anchorMap.set(this.anchor, this.result);
}
break;
}
}
} else if (this.typeMap[this.kind ?? "fallback"].has(this.tag)) {
const map = this.typeMap[this.kind ?? "fallback"];
type = map.get(this.tag)!;
if (this.result !== null && type.kind !== this.kind) {
return this.throwError(
`Unacceptable node kind for !<${this.tag}> tag: it should be "${type.kind}", not "${this.kind}"`,
);
}
if (!type.resolve(this.result)) {
// `state.result` updated in resolver if matched
return this.throwError(
`Cannot resolve a node with !<${this.tag}> explicit tag`,
);
} else {
this.result = type.construct(this.result);
if (this.anchor !== null) {
this.anchorMap.set(this.anchor, this.result);
}
}
} else {
return this.throwError(`Cannot resolve unknown tag !<${this.tag}>`);
}
}
return this.tag !== null || this.anchor !== null || hasContent;
}
readDocument() {
const documentStart = this.position;
let position: number;
let directiveName: string;
let directiveArgs: string[];
let hasDirectives = false;
let ch: number;
this.version = null;
this.checkLineBreaks = false;
this.tagMap = new Map();
this.anchorMap = new Map();
while ((ch = this.peek()) !== 0) {
this.skipSeparationSpace(true, -1);
ch = this.peek();
if (this.lineIndent > 0 || ch !== PERCENT) {
break;
}
hasDirectives = true;
ch = this.next();
position = this.position;
while (ch !== 0 && !isWhiteSpaceOrEOL(ch)) {
ch = this.next();
}
directiveName = this.input.slice(position, this.position);
directiveArgs = [];
if (directiveName.length < 1) {
return this.throwError(
"Cannot read document: directive name length must be greater than zero",
);
}
while (ch !== 0) {
while (isWhiteSpace(ch)) {
ch = this.next();
}
if (ch === SHARP) {
do {
ch = this.next();
} while (ch !== 0 && !isEOL(ch));
break;
}
if (isEOL(ch)) break;
position = this.position;
while (ch !== 0 && !isWhiteSpaceOrEOL(ch)) {
ch = this.next();
}
directiveArgs.push(this.input.slice(position, this.position));
}
if (ch !== 0) this.readLineBreak();
switch (directiveName) {
case "YAML":
this.yamlDirectiveHandler(...directiveArgs);
break;
case "TAG":
this.tagDirectiveHandler(...directiveArgs);
break;
default:
this.dispatchWarning(
`unknown document directive "${directiveName}"`,
);
break;
}
}
this.skipSeparationSpace(true, -1);
if (
this.lineIndent === 0 &&
this.peek() === MINUS &&
this.peek(1) === MINUS &&
this.peek(2) === MINUS
) {
this.position += 3;
this.skipSeparationSpace(true, -1);
} else if (hasDirectives) {
return this.throwError(
"Cannot read document: directives end mark is expected",
);
}
this.composeNode(this.lineIndent - 1, CONTEXT_BLOCK_OUT, false, true);
this.skipSeparationSpace(true, -1);
if (
this.checkLineBreaks &&
PATTERN_NON_ASCII_LINE_BREAKS.test(
this.input.slice(documentStart, this.position),
)
) {
this.dispatchWarning("non-ASCII line breaks are interpreted as content");
}
if (this.position === this.lineStart && this.testDocumentSeparator()) {
if (this.peek() === DOT) {
this.position += 3;
this.skipSeparationSpace(true, -1);
}
} else if (this.position < this.length - 1) {
return this.throwError(
"Cannot read document: end of the stream or a document separator is expected",
);
}
return this.result;
}
*readDocuments() {
while (this.position < this.length - 1) {
yield this.readDocument();
}
}
}