@@ -8,14 +8,18 @@ const assert = require('node:assert/strict');
88const stackFramesRegexp = / ( \s + ) ( ( .+ ?) \s + \( ) ? (?: \( ? ( .+ ?) : ( \d + ) (?: : ( \d + ) ) ? ) \) ? ( \s + \{ ) ? ( \n | $ ) / g;
99const windowNewlineRegexp = / \r / g;
1010
11- function replaceStackTrace ( str ) {
12- return str . replace ( stackFramesRegexp , '$1*$7\n' ) ;
11+ function replaceStackTrace ( str , replacement = '$1*$7\n' ) {
12+ return str . replace ( stackFramesRegexp , replacement ) ;
1313}
1414
1515function replaceWindowsLineEndings ( str ) {
1616 return str . replace ( windowNewlineRegexp , '' ) ;
1717}
1818
19+ function replaceWindowsPaths ( str ) {
20+ return str . replaceAll ( path . win32 . sep , path . posix . sep ) ;
21+ }
22+
1923function transform ( ...args ) {
2024 return ( str ) => args . reduce ( ( acc , fn ) => fn ( acc ) , str ) ;
2125}
@@ -35,19 +39,32 @@ async function assertSnapshot(actual, filename = process.argv[1]) {
3539 }
3640}
3741
42+ /**
43+ * Spawn a process and assert its output against a snapshot.
44+ * if you want to automatically update the snapshot, run tests with NODE_REGENERATE_SNAPSHOTS=1
45+ * transform is a function that takes the output and returns a string that will be compared against the snapshot
46+ * this is useful for normalizing output such as stack traces
47+ * there are some predefined transforms in this file such as replaceStackTrace and replaceWindowsLineEndings
48+ * both of which can be used as an example for writing your own
49+ * compose multiple transforms by passing them as arguments to the transform function:
50+ * assertSnapshot.transform(assertSnapshot.replaceStackTrace, assertSnapshot.replaceWindowsLineEndings)
51+ *
52+ * @param {string } filename
53+ * @param {function(string): string } [transform]
54+ * @returns {Promise<void> }
55+ */
3856async function spawnAndAssert ( filename , transform = ( x ) => x ) {
39- // TODO: Add an option to this function to alternatively or additionally compare stderr.
40- // For now, tests that want to check stderr or both stdout and stderr can use spawnPromisified.
4157 const flags = common . parseTestFlags ( filename ) ;
42- const { stdout } = await common . spawnPromisified ( process . execPath , [ ...flags , filename ] ) ;
43- await assertSnapshot ( transform ( stdout ) , filename ) ;
58+ const { stdout, stderr } = await common . spawnPromisified ( process . execPath , [ ...flags , filename ] ) ;
59+ await assertSnapshot ( transform ( ` ${ stdout } ${ stderr } ` ) , filename ) ;
4460}
4561
4662module . exports = {
4763 assertSnapshot,
4864 getSnapshotPath,
4965 replaceStackTrace,
5066 replaceWindowsLineEndings,
67+ replaceWindowsPaths,
5168 spawnAndAssert,
5269 transform,
5370} ;
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