qmllint: Properly warn about calling properties

Previously whenever a property was called the warnings qmllint emitted
made it seem like the property was just not found instead of not being
callable.

Now we will warn if you try to call a property and warn about
properties shadowing methods, slots or signals. We also discourage
calling variant properties now that may or may not be a function.

This change also fixes an assert being hit in isMissingPropertyType
due to our previous, lackluster checks.

Fixes: QTBUG-101074
Change-Id: I0790b4a4584f3430ee1d8ddf549611225a36cc5b
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
(cherry picked from commit 1829d7c64c1d8d5b42241135bfead030521cb398)

7 files changed, 63 insertions, 0 deletions

diff --git a/tests/auto/qml/qmllint/data/callJSValueProp.qml b/tests/auto/qml/qmllint/data/callJSValueProp.qml
new file mode 100644
index 0000000000..357c810383
--- /dev/null
+++ b/tests/auto/qml/qmllint/data/callJSValueProp.qml
@@ -0,0 +1,6 @@
+import QtQml
+
+QtObject {
+    function foo() {}
+    Component.onCompleted: Qt.callLater(foo);
+}
diff --git a/tests/auto/qml/qmllint/data/callVarProp.qml b/tests/auto/qml/qmllint/data/callVarProp.qml
new file mode 100644
index 0000000000..ad69e2a679
--- /dev/null
+++ b/tests/auto/qml/qmllint/data/callVarProp.qml
@@ -0,0 +1,7 @@
+import QtQml
+
+QtObject {
+    property var foo: () => {}
+
+    Component.onCompleted: foo()
+}
diff --git a/tests/auto/qml/qmllint/data/shadowedMethod.qml b/tests/auto/qml/qmllint/data/shadowedMethod.qml
new file mode 100644
index 0000000000..72f18aaec7
--- /dev/null
+++ b/tests/auto/qml/qmllint/data/shadowedMethod.qml
@@ -0,0 +1,8 @@
+import QtQuick
+
+QtObject {
+    function foo() {}
+    property bool foo: false
+
+    Component.onCompleted: foo()
+}
diff --git a/tests/auto/qml/qmllint/data/shadowedSignal.qml b/tests/auto/qml/qmllint/data/shadowedSignal.qml
new file mode 100644
index 0000000000..e4bb003495
--- /dev/null
+++ b/tests/auto/qml/qmllint/data/shadowedSignal.qml
@@ -0,0 +1,6 @@
+import QtQuick
+
+MouseArea {
+    id: mouseArea
+    Component.onCompleted: pressed()
+}
diff --git a/tests/auto/qml/qmllint/data/shadowedSignalWithId.qml b/tests/auto/qml/qmllint/data/shadowedSignalWithId.qml
new file mode 100644
index 0000000000..ed7cc9f6c4
--- /dev/null
+++ b/tests/auto/qml/qmllint/data/shadowedSignalWithId.qml
@@ -0,0 +1,6 @@
+import QtQuick
+
+MouseArea {
+    id: mouseArea
+    Component.onCompleted: mouseArea.pressed()
+}
diff --git a/tests/auto/qml/qmllint/data/shadowedSlot.qml b/tests/auto/qml/qmllint/data/shadowedSlot.qml
new file mode 100644
index 0000000000..cb09645746
--- /dev/null
+++ b/tests/auto/qml/qmllint/data/shadowedSlot.qml
@@ -0,0 +1,6 @@
+import QtQml
+
+ObjectModel {
+    property bool move: false
+    Component.onCompleted: move()
+}
diff --git a/tests/auto/qml/qmllint/tst_qmllint.cpp b/tests/auto/qml/qmllint/tst_qmllint.cpp
index 20819b30e6..31faaacc07 100644
--- a/tests/auto/qml/qmllint/tst_qmllint.cpp
+++ b/tests/auto/qml/qmllint/tst_qmllint.cpp
@@ -812,6 +812,30 @@ void TestQmllint::dirtyQmlCode_data()
             << QStringLiteral("badCppPropertyChangeHandlers4.qml")
             << QStringLiteral("no matching signal found for handler \"onWannabeSignal\"")
             << QString() << QString() << false;
+    QTest::newRow("shadowedSignal")
+            << QStringLiteral("shadowedSignal.qml")
+            << QStringLiteral("Signal \"pressed\" is shadowed by a property.") << QString()
+            << QString() << false;
+    QTest::newRow("shadowedSignalWithId")
+            << QStringLiteral("shadowedSignalWithId.qml")
+            << QStringLiteral("Signal \"pressed\" is shadowed by a property") << QString()
+            << QString() << false;
+    QTest::newRow("shadowedSlot") << QStringLiteral("shadowedSlot.qml")
+                                  << QStringLiteral("Slot \"move\" is shadowed by a property")
+                                  << QString() << QString() << false;
+    QTest::newRow("shadowedMethod") << QStringLiteral("shadowedMethod.qml")
+                                    << QStringLiteral("Method \"foo\" is shadowed by a property.")
+                                    << QString() << QString() << false;
+    QTest::newRow("callVarProp")
+            << QStringLiteral("callVarProp.qml")
+            << QStringLiteral("Property \"foo\" is a variant property. It may or may not be a "
+                              "method. Use a regular function instead.")
+            << QString() << QString() << false;
+    QTest::newRow("callJSValue")
+            << QStringLiteral("callJSValueProp.qml")
+            << QStringLiteral("Property \"callLater\" is a QJSValue property. It may or may not be "
+                              "a method. Use a regular Q_INVOKABLE instead.")
+            << QString() << QString() << false;
 }
 
 void TestQmllint::dirtyQmlCode()