fix(packaging): make source archive inspection portable

tools/packaging/release-snap-assets.test.mjs

@@ -904,6 +904,45 @@ test('hashes the final source archive bytes and reads the exact packaged Snap bi
     assert.equal(tarResult.error, undefined);
     assert.equal(tarResult.status, 0, tarResult.stderr);
 
+    let observedTarFilesFromFile = false;
+    const runCommand = (command, args, options = {}) => {
+        if (command === 'tar' && args.includes('-T')) {
+            const filesFromPath = args[args.indexOf('-T') + 1];
+            assert.equal(path.isAbsolute(filesFromPath), true);
+            assert.equal(fs.lstatSync(filesFromPath).isFile(), true);
+            assert.equal(
+                fs.lstatSync(filesFromPath).mode & 0o077,
+                0,
+                'tar files-from input must not be group/world accessible'
+            );
+            assert.match(
+                fs.readFileSync(filesFromPath, 'utf8'),
+                /git\/libplacebo\/README\.md/
+            );
+            observedTarFilesFromFile = true;
+        }
+        const result = childProcess.spawnSync(command, args, {
+            encoding:
+                options.encoding === undefined ? 'utf8' : options.encoding,
+            input: options.input,
+            killSignal: 'SIGKILL',
+            maxBuffer: options.maxBuffer,
+            stdio: 'pipe',
+            timeout: options.timeout,
+            windowsHide: true,
+        });
+        if (result.error) {
+            throw result.error;
+        }
+        if (result.status !== 0) {
+            throw new Error(
+                `${command} exited with status ${String(result.status)}: ${
+                    result.stderr ?? ''
+                }`
+            );
+        }
+        return result.stdout;
+    };
     const sourceArchive = sourceArchiveContract.createLinuxSourceArchiveBinding(
         {
             archivePath: sourceArchivePath,
@@ -911,15 +950,20 @@ test('hashes the final source archive bytes and reads the exact packaged Snap bi
         }
     );
     assert.throws(
-        () => sourceBindingHelper.inspectSourceArchive(sourceArchivePath),
+        () =>
+            sourceBindingHelper.inspectSourceArchive(sourceArchivePath, {
+                runCommand,
+            }),
         /snapshot digest mismatch/i
     );
     const sourceInspection = sourceBindingHelper.inspectSourceArchive(
         sourceArchivePath,
         {
             expectedSourceSnapshotSha256: fixture.expectedSourceSnapshotSha256,
+            runCommand,
         }
     );
+    assert.equal(observedTarFilesFromFile, true);
     assert.equal(sourceInspection.archiveSha256, sourceArchive.sha256);
     assert.deepEqual(sourceInspection.archiveFiles, sourceIndex.archives);
 

tools/packaging/release-snap-source-binding.cjs

@@ -546,6 +546,19 @@ function inspectLibplaceboSourceSnapshot(
         path.join(os.tmpdir(), 'iptvnator-libplacebo-source-verifier-')
     );
     try {
+        const memberListPath = path.join(
+            temporaryRoot,
+            'libplacebo-members.txt'
+        );
+        fs.writeFileSync(
+            memberListPath,
+            `${sourceMembers.map(({ rawName }) => rawName).join('\n')}\n`,
+            {
+                encoding: 'utf8',
+                flag: 'wx',
+                mode: 0o600,
+            }
+        );
         runCommand(
             'tar',
             [
@@ -558,14 +571,10 @@ function inspectLibplaceboSourceSnapshot(
                 '--no-same-owner',
                 '--no-same-permissions',
                 '-T',
-                '/dev/stdin',
+                memberListPath,
             ],
             {
                 encoding: 'utf8',
-                input: Buffer.from(
-                    `${sourceMembers.map(({ rawName }) => rawName).join('\n')}\n`,
-                    'utf8'
-                ),
                 maxBuffer: COMMAND_OUTPUT_MAX_BUFFER_BYTES,
             }
         );