tree-sitter/crates/generate/src/dsl.js

563 lines
14 KiB
JavaScript

function alias(rule, value) {
const result = {
type: "ALIAS",
content: normalize(rule),
named: false,
value: null
};
switch (value.constructor) {
case String:
result.named = false;
result.value = value;
return result;
case ReferenceError:
result.named = true;
result.value = value.symbol.name;
return result;
case Object:
case GrammarSymbol:
if (typeof value.type === 'string' && value.type === 'SYMBOL') {
result.named = true;
result.value = value.name;
return result;
}
}
throw new Error(`Invalid alias value ${value}`);
}
function blank() {
return {
type: "BLANK"
};
}
function field(name, rule) {
return {
type: "FIELD",
name,
content: normalize(rule)
}
}
function choice(...elements) {
return {
type: "CHOICE",
members: elements.map(normalize)
};
}
function optional(value) {
checkArguments(arguments, arguments.length, optional, 'optional');
return choice(value, blank());
}
function prec(number, rule) {
checkPrecedence(number);
checkArguments(
arguments,
arguments.length - 1,
prec,
'prec',
' and a precedence argument'
);
return {
type: "PREC",
value: number,
content: normalize(rule)
};
}
prec.left = function (number, rule) {
if (rule == null) {
rule = number;
number = 0;
}
checkPrecedence(number);
checkArguments(
arguments,
arguments.length - 1,
prec.left,
'prec.left',
' and an optional precedence argument'
);
return {
type: "PREC_LEFT",
value: number,
content: normalize(rule)
};
}
prec.right = function (number, rule) {
if (rule == null) {
rule = number;
number = 0;
}
checkPrecedence(number);
checkArguments(
arguments,
arguments.length - 1,
prec.right,
'prec.right',
' and an optional precedence argument'
);
return {
type: "PREC_RIGHT",
value: number,
content: normalize(rule)
};
}
prec.dynamic = function (number, rule) {
checkPrecedence(number);
checkArguments(
arguments,
arguments.length - 1,
prec.dynamic,
'prec.dynamic',
' and a precedence argument'
);
return {
type: "PREC_DYNAMIC",
value: number,
content: normalize(rule)
};
}
function repeat(rule) {
checkArguments(arguments, arguments.length, repeat, 'repeat');
return {
type: "REPEAT",
content: normalize(rule)
};
}
function repeat1(rule) {
checkArguments(arguments, arguments.length, repeat1, 'repeat1');
return {
type: "REPEAT1",
content: normalize(rule)
};
}
function seq(...elements) {
return {
type: "SEQ",
members: elements.map(normalize)
};
}
class GrammarSymbol {
constructor(name) {
this.type = "SYMBOL";
this.name = name;
}
}
function reserved(wordset, rule) {
if (typeof wordset !== 'string') {
throw new Error('Invalid reserved word set name: ' + wordset)
}
return {
type: "RESERVED",
content: normalize(rule),
context_name: wordset,
}
}
function sym(name) {
return new GrammarSymbol(name);
}
function token(value) {
checkArguments(arguments, arguments.length, token, 'token', '', 'literal');
return {
type: "TOKEN",
content: normalize(value)
};
}
token.immediate = function (value) {
checkArguments(arguments, arguments.length, token.immediate, 'token.immediate', '', 'literal');
return {
type: "IMMEDIATE_TOKEN",
content: normalize(value)
};
}
function normalize(value) {
if (typeof value == "undefined")
throw new Error("Undefined symbol");
switch (value.constructor) {
case String:
return {
type: 'STRING',
value
};
case RegExp:
return value.flags ? {
type: 'PATTERN',
value: value.source,
flags: value.flags
} : {
type: 'PATTERN',
value: value.source
};
case RustRegex:
return {
type: 'PATTERN',
value: value.value
};
case ReferenceError:
throw value
default:
if (typeof value.type === 'string') {
return value;
} else {
throw new TypeError(`Invalid rule: ${value}`);
}
}
}
function RuleBuilder(ruleMap) {
return new Proxy({}, {
get(_, propertyName) {
const symbol = sym(propertyName);
if (!ruleMap || Object.prototype.hasOwnProperty.call(ruleMap, propertyName)) {
return symbol;
} else {
const error = new ReferenceError(`Undefined symbol '${propertyName}'`);
error.symbol = symbol;
return error;
}
}
})
}
function grammar(baseGrammar, options) {
let inherits = undefined;
if (!options) {
options = baseGrammar;
baseGrammar = {
name: null,
rules: {},
extras: [normalize(/\s/)],
conflicts: [],
externals: [],
inline: [],
supertypes: [],
precedences: [],
reserved: {},
};
} else {
baseGrammar = baseGrammar.grammar;
inherits = baseGrammar.name;
}
let externals = baseGrammar.externals;
if (options.externals) {
if (typeof options.externals !== "function") {
throw new Error("Grammar's 'externals' property must be a function.");
}
const externalsRuleBuilder = RuleBuilder(null)
const externalRules = options.externals.call(externalsRuleBuilder, externalsRuleBuilder, baseGrammar.externals);
if (!Array.isArray(externalRules)) {
throw new Error("Grammar's 'externals' property must return an array of rules.");
}
externals = externalRules.map(normalize);
}
const ruleMap = {};
for (const key of Object.keys(options.rules)) {
ruleMap[key] = true;
}
for (const key of Object.keys(baseGrammar.rules)) {
ruleMap[key] = true;
}
for (const external of externals) {
if (typeof external.name === 'string') {
ruleMap[external.name] = true;
}
}
const ruleBuilder = RuleBuilder(ruleMap);
const name = options.name;
if (typeof name !== "string") {
throw new Error("Grammar's 'name' property must be a string.");
}
if (!/^[a-zA-Z_]\w*$/.test(name)) {
throw new Error("Grammar's 'name' property must not start with a digit and cannot contain non-word characters.");
}
if (inherits && typeof inherits !== "string") {
throw new Error("Base grammar's 'name' property must be a string.");
}
if (inherits && !/^[a-zA-Z_]\w*$/.test(name)) {
throw new Error("Base grammar's 'name' property must not start with a digit and cannot contain non-word characters.");
}
const rules = Object.assign({}, baseGrammar.rules);
if (options.rules) {
if (typeof options.rules !== "object") {
throw new Error("Grammar's 'rules' property must be an object.");
}
for (const ruleName of Object.keys(options.rules)) {
const ruleFn = options.rules[ruleName];
if (typeof ruleFn !== "function") {
throw new Error(`Grammar rules must all be functions. '${ruleName}' rule is not.`);
}
const rule = ruleFn.call(ruleBuilder, ruleBuilder, baseGrammar.rules[ruleName]);
if (rule === undefined) {
throw new Error(`Rule '${ruleName}' returned undefined.`);
}
rules[ruleName] = normalize(rule);
}
}
let reserved = baseGrammar.reserved;
if (options.reserved) {
if (typeof options.reserved !== "object") {
throw new Error("Grammar's 'reserved' property must be an object.");
}
for (const reservedWordSetName of Object.keys(options.reserved)) {
const reservedWordSetFn = options.reserved[reservedWordSetName]
if (typeof reservedWordSetFn !== "function") {
throw new Error(`Grammar reserved word sets must all be functions. '${reservedWordSetName}' is not.`);
}
const reservedTokens = reservedWordSetFn.call(ruleBuilder, ruleBuilder, baseGrammar.reserved[reservedWordSetName]);
if (!Array.isArray(reservedTokens)) {
throw new Error(`Grammar's reserved word set functions must all return arrays of rules. '${reservedWordSetName}' does not.`);
}
reserved[reservedWordSetName] = reservedTokens.map(normalize);
}
}
let extras = baseGrammar.extras.slice();
if (options.extras) {
if (typeof options.extras !== "function") {
throw new Error("Grammar's 'extras' property must be a function.");
}
extras = options.extras
.call(ruleBuilder, ruleBuilder, baseGrammar.extras)
if (!Array.isArray(extras)) {
throw new Error("Grammar's 'extras' function must return an array.")
}
extras = extras.map(normalize);
}
let word = baseGrammar.word;
if (options.word) {
word = options.word.call(ruleBuilder, ruleBuilder).name;
if (typeof word != 'string') {
throw new Error("Grammar's 'word' property must be a named rule.");
}
if (word === 'ReferenceError') {
throw new Error("Grammar's 'word' property must be a valid rule name.");
}
}
let conflicts = baseGrammar.conflicts;
if (options.conflicts) {
if (typeof options.conflicts !== "function") {
throw new Error("Grammar's 'conflicts' property must be a function.");
}
const baseConflictRules = baseGrammar.conflicts.map(conflict => conflict.map(sym));
const conflictRules = options.conflicts.call(ruleBuilder, ruleBuilder, baseConflictRules);
if (!Array.isArray(conflictRules)) {
throw new Error("Grammar's conflicts must be an array of arrays of rules.");
}
conflicts = conflictRules.map(conflictSet => {
if (!Array.isArray(conflictSet)) {
throw new Error("Grammar's conflicts must be an array of arrays of rules.");
}
return conflictSet.map(symbol => normalize(symbol).name);
});
}
let inline = baseGrammar.inline;
if (options.inline) {
if (typeof options.inline !== "function") {
throw new Error("Grammar's 'inline' property must be a function.");
}
const baseInlineRules = baseGrammar.inline.map(sym);
const inlineRules = options.inline.call(ruleBuilder, ruleBuilder, baseInlineRules);
if (!Array.isArray(inlineRules)) {
throw new Error("Grammar's inline must be an array of rules.");
}
inline = inlineRules.filter((symbol, index, self) => {
if (self.findIndex(s => s.name === symbol.name) !== index) {
console.log(`Warning: duplicate inline rule '${symbol.name}'`);
return false;
}
if (symbol.name === 'ReferenceError') {
console.log(`Warning: inline rule '${symbol.symbol.name}' is not defined.`);
return false;
}
return true;
}).map(symbol => symbol.name);
}
let supertypes = baseGrammar.supertypes;
if (options.supertypes) {
if (typeof options.supertypes !== "function") {
throw new Error("Grammar's 'supertypes' property must be a function.");
}
const baseSupertypeRules = baseGrammar.supertypes.map(sym);
const supertypeRules = options.supertypes.call(ruleBuilder, ruleBuilder, baseSupertypeRules);
if (!Array.isArray(supertypeRules)) {
throw new Error("Grammar's supertypes must be an array of rules.");
}
supertypes = supertypeRules.map(symbol => {
if (symbol.name === 'ReferenceError') {
throw new Error(`Supertype rule \`${symbol.symbol.name}\` is not defined.`);
}
return symbol.name;
});
}
let precedences = baseGrammar.precedences;
if (options.precedences) {
if (typeof options.precedences !== "function") {
throw new Error("Grammar's 'precedences' property must be a function");
}
precedences = options.precedences.call(ruleBuilder, ruleBuilder, baseGrammar.precedences);
if (!Array.isArray(precedences)) {
throw new Error("Grammar's precedences must be an array of arrays of rules.");
}
precedences = precedences.map(list => {
if (!Array.isArray(list)) {
throw new Error("Grammar's precedences must be an array of arrays of rules.");
}
return list.map(normalize);
});
}
if (Object.keys(rules).length === 0) {
throw new Error("Grammar must have at least one rule.");
}
return {
grammar: {
name,
inherits,
word,
rules,
extras,
conflicts,
precedences,
externals,
inline,
supertypes,
reserved,
},
};
}
class RustRegex {
constructor(value) {
this.value = value;
}
}
function checkArguments(args, ruleCount, caller, callerName, suffix = '', argType = 'rule') {
// Allow for .map() usage where additional arguments are index and the entire array.
const isMapCall = ruleCount === 3 && typeof args[1] === 'number' && Array.isArray(args[2]);
if (isMapCall) {
ruleCount = typeof args[2] === 'number' ? 1 : args[2].length;
}
if (ruleCount > 1 && !isMapCall) {
const error = new Error([
`The \`${callerName}\` function only takes one ${argType} argument${suffix}.`,
`You passed in multiple ${argType}s. Did you mean to call \`seq\`?\n`
].join('\n'));
Error.captureStackTrace(error, caller);
throw error
}
}
function checkPrecedence(value) {
if (value == null) {
throw new Error('Missing precedence value');
}
}
function getEnv(name) {
if (globalThis.native) return globalThis.__ts_grammar_path;
if (globalThis.process) return process.env[name]; // Node/Bun
if (globalThis.Deno) return Deno.env.get(name); // Deno
throw Error("Unsupported JS runtime");
}
globalThis.alias = alias;
globalThis.blank = blank;
globalThis.choice = choice;
globalThis.optional = optional;
globalThis.prec = prec;
globalThis.repeat = repeat;
globalThis.repeat1 = repeat1;
globalThis.reserved = reserved;
globalThis.seq = seq;
globalThis.sym = sym;
globalThis.token = token;
globalThis.grammar = grammar;
globalThis.field = field;
globalThis.RustRegex = RustRegex;
const grammarPath = getEnv("TREE_SITTER_GRAMMAR_PATH");
let result = await import(grammarPath);
let grammarObj = result.default?.grammar ?? result.grammar;
if (globalThis.native && !grammarObj) {
grammarObj = module.exports.grammar;
}
const object = {
"$schema": "https://tree-sitter.github.io/tree-sitter/assets/schemas/grammar.schema.json",
...grammarObj,
};
const output = JSON.stringify(object);
if (globalThis.native) {
globalThis.output = output;
} else if (globalThis.process) { // Node/Bun
process.stdout.write(output);
} else if (globalThis.Deno) { // Deno
Deno.stdout.writeSync(new TextEncoder().encode(output));
} else {
throw Error("Unsupported JS runtime");
}