qmllint: Fix diagnostics output for test run

We do want to see the output if the cleanQmlCode test fails.

Change-Id: I6b7e9d3412af9fffac68d2e394418de2faf09626
Reviewed-by: Maximilian Goldstein <max.goldstein@qt.io>

src/qmllint/qqmllinter.cpp

@@ -121,7 +121,11 @@ bool QQmlLinter::lintFile(const QString &filename, const QString *fileContents,
         QFile file(filename);
         if (!file.open(QFile::ReadOnly)) {
             if (json) {
-                result[u"openFailed"] = true;
+                addJsonWarning(QQmlJS::DiagnosticMessage {
+                    QStringLiteral("Failed to open file %1: %2").arg(filename, file.errorString()),
+                    QtCriticalMsg,
+                    QQmlJS::SourceLocation()
+                });
                 success = false;
             } else if (!silent) {
                 qWarning() << "Failed to open file" << filename << file.error();

tests/auto/qml/qmllint/tst_qmllint.cpp

@@ -1048,14 +1048,14 @@ void TestQmllint::callQmllint(const QString &fileToLint, bool shouldSucceed, QJs
 
     bool success = m_linter.lintFile(QFileInfo(fileToLint).isAbsolute() ? fileToLint
                                                                         : testFile(fileToLint),
-                                     nullptr, true, warnings ? &jsonOutput : nullptr,
+                                     nullptr, false, warnings ? &jsonOutput : nullptr,
                                      m_defaultImportPaths, QStringList(), QStringList(), {});
-    QCOMPARE(success, shouldSucceed);
-
     if (warnings) {
-        Q_ASSERT(jsonOutput.size() == 1);
+        QVERIFY2(jsonOutput.size() == 1, QJsonDocument(jsonOutput).toJson());
         *warnings = jsonOutput.at(0)[u"warnings"_qs].toArray();
     }
+
+    QCOMPARE(success, shouldSucceed);
 }
 
 void TestQmllint::requiredProperty()

tools/qmllint/main.cpp

@@ -51,7 +51,7 @@
 
 #include <cstdio>
 
-constexpr int JSON_LOGGING_FORMAT_REVISION = 1;
+constexpr int JSON_LOGGING_FORMAT_REVISION = 2;
 
 int main(int argv, char *argc[])
 {