Initial commit

node_modules/execa/lib/stdio/native.js

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+import {readFileSync} from 'node:fs';
+import tty from 'node:tty';
+import {isStream as isNodeStream} from 'is-stream';
+import {STANDARD_STREAMS} from '../utils/standard-stream.js';
+import {bufferToUint8Array} from '../utils/uint-array.js';
+import {serializeOptionValue} from '../arguments/fd-options.js';
+
+// When we use multiple `stdio` values for the same streams, we pass 'pipe' to `child_process.spawn()`.
+// We then emulate the piping done by core Node.js.
+// To do so, we transform the following values:
+//  - Node.js streams are marked as `type: nodeStream`
+//  - 'inherit' becomes `process.stdin|stdout|stderr`
+//  - any file descriptor integer becomes `process.stdio[fdNumber]`
+// All of the above transformations tell Execa to perform manual piping.
+export const handleNativeStream = ({stdioItem, stdioItem: {type}, isStdioArray, fdNumber, direction, isSync}) => {
+	if (!isStdioArray || type !== 'native') {
+		return stdioItem;
+	}
+
+	return isSync
+		? handleNativeStreamSync({stdioItem, fdNumber, direction})
+		: handleNativeStreamAsync({stdioItem, fdNumber});
+};
+
+// Synchronous methods use a different logic.
+// 'inherit', file descriptors and process.std* are handled by readFileSync()/writeFileSync().
+const handleNativeStreamSync = ({stdioItem, stdioItem: {value, optionName}, fdNumber, direction}) => {
+	const targetFd = getTargetFd({
+		value,
+		optionName,
+		fdNumber,
+		direction,
+	});
+	if (targetFd !== undefined) {
+		return targetFd;
+	}
+
+	if (isNodeStream(value, {checkOpen: false})) {
+		throw new TypeError(`The \`${optionName}: Stream\` option cannot both be an array and include a stream with synchronous methods.`);
+	}
+
+	return stdioItem;
+};
+
+const getTargetFd = ({value, optionName, fdNumber, direction}) => {
+	const targetFdNumber = getTargetFdNumber(value, fdNumber);
+	if (targetFdNumber === undefined) {
+		return;
+	}
+
+	if (direction === 'output') {
+		return {type: 'fileNumber', value: targetFdNumber, optionName};
+	}
+
+	if (tty.isatty(targetFdNumber)) {
+		throw new TypeError(`The \`${optionName}: ${serializeOptionValue(value)}\` option is invalid: it cannot be a TTY with synchronous methods.`);
+	}
+
+	return {type: 'uint8Array', value: bufferToUint8Array(readFileSync(targetFdNumber)), optionName};
+};
+
+const getTargetFdNumber = (value, fdNumber) => {
+	if (value === 'inherit') {
+		return fdNumber;
+	}
+
+	if (typeof value === 'number') {
+		return value;
+	}
+
+	const standardStreamIndex = STANDARD_STREAMS.indexOf(value);
+	if (standardStreamIndex !== -1) {
+		return standardStreamIndex;
+	}
+};
+
+const handleNativeStreamAsync = ({stdioItem, stdioItem: {value, optionName}, fdNumber}) => {
+	if (value === 'inherit') {
+		return {type: 'nodeStream', value: getStandardStream(fdNumber, value, optionName), optionName};
+	}
+
+	if (typeof value === 'number') {
+		return {type: 'nodeStream', value: getStandardStream(value, value, optionName), optionName};
+	}
+
+	if (isNodeStream(value, {checkOpen: false})) {
+		return {type: 'nodeStream', value, optionName};
+	}
+
+	return stdioItem;
+};
+
+// Node.js does not allow to easily retrieve file descriptors beyond stdin/stdout/stderr as streams.
+//  - `fs.createReadStream()`/`fs.createWriteStream()` with the `fd` option do not work with character devices that use blocking reads/writes (such as interactive TTYs).
+//  - Using a TCP `Socket` would work but be rather complex to implement.
+// Since this is an edge case, we simply throw an error message.
+// See https://github.com/sindresorhus/execa/pull/643#discussion_r1435905707
+const getStandardStream = (fdNumber, value, optionName) => {
+	const standardStream = STANDARD_STREAMS[fdNumber];
+
+	if (standardStream === undefined) {
+		throw new TypeError(`The \`${optionName}: ${value}\` option is invalid: no such standard stream.`);
+	}
+
+	return standardStream;
+};