From 2733ce26dc5691fb63e11c9803c642111b853192 Mon Sep 17 00:00:00 2001
From: ankur22 <ankur.agarwal@grafana.com>
Date: Wed, 15 Nov 2023 15:12:32 +0000
Subject: [PATCH 1/3] Fix error on nil result on page.query

When page.query (page.$ in the js test script) is used, if no element
matches the selector then it used to return an error. The expected
behaviour is that it returns nil in this case.
---
 common/element_handle.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/common/element_handle.go b/common/element_handle.go
index 5c5becc84..062e47125 100644
--- a/common/element_handle.go
+++ b/common/element_handle.go
@@ -1042,7 +1042,7 @@ func (h *ElementHandle) Query(selector string) (*ElementHandle, error) {
 		return nil, fmt.Errorf("querying selector %q: %w", selector, err)
 	}
 	if result == nil {
-		return nil, fmt.Errorf("querying selector %q", selector)
+		return nil, nil //nolint:nilnil
 	}
 	handle, ok := result.(JSHandleAPI)
 	if !ok {

From c97deb656f4c8bd99dd86aa9c02a05d01d013972 Mon Sep 17 00:00:00 2001
From: ankur22 <ankur.agarwal@grafana.com>
Date: Wed, 15 Nov 2023 15:28:57 +0000
Subject: [PATCH 2/3] Update mapping to avoid mapping nil elementHandle

If the result of query is nil, we shouldn't map this to an
elementHandle, since the expectation on a nil result in query is null
in the ks test script. If we map the nil result, the result is no
longer null in the js test script.
---
 browser/mapping.go | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/browser/mapping.go b/browser/mapping.go
index 08672e480..02d235aea 100644
--- a/browser/mapping.go
+++ b/browser/mapping.go
@@ -253,6 +253,12 @@ func mapElementHandle(vu moduleVU, eh *common.ElementHandle) mapping {
 		if err != nil {
 			return nil, err //nolint:wrapcheck
 		}
+		// ElementHandle can be null when the selector does not match any elements.
+		// We do not want to map nil elementHandles since the expectation is a
+		// null result in the test script for this case.
+		if eh == nil {
+			return nil, nil //nolint:nilnil
+		}
 		ehm := mapElementHandle(vu, eh)
 		return ehm, nil
 	}
@@ -396,6 +402,12 @@ func mapFrame(vu moduleVU, f *common.Frame) mapping {
 		if err != nil {
 			return nil, err //nolint:wrapcheck
 		}
+		// ElementHandle can be null when the selector does not match any elements.
+		// We do not want to map nil elementHandles since the expectation is a
+		// null result in the test script for this case.
+		if eh == nil {
+			return nil, nil //nolint:nilnil
+		}
 		ehm := mapElementHandle(vu, eh)
 		return ehm, nil
 	}
@@ -594,6 +606,12 @@ func mapPage(vu moduleVU, p *common.Page) mapping {
 		if err != nil {
 			return nil, err //nolint:wrapcheck
 		}
+		// ElementHandle can be null when the selector does not match any elements.
+		// We do not want to map nil elementHandles since the expectation is a
+		// null result in the test script for this case.
+		if eh == nil {
+			return nil, nil //nolint:nilnil
+		}
 		ehm := mapElementHandle(vu, eh)
 		return ehm, nil
 	}

From f4708eeffd87ce4e70969314ed6520435c58051f Mon Sep 17 00:00:00 2001
From: ankur22 <ankur.agarwal@grafana.com>
Date: Wed, 15 Nov 2023 15:14:24 +0000
Subject: [PATCH 3/3] Add a integration test for page.query

---
 tests/element_handle_test.go | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/tests/element_handle_test.go b/tests/element_handle_test.go
index 4dd91dd29..5a8e790b6 100644
--- a/tests/element_handle_test.go
+++ b/tests/element_handle_test.go
@@ -439,3 +439,15 @@ func TestElementHandlePress(t *testing.T) {
 
 	require.Equal(t, "AbC", el.InputValue(nil))
 }
+
+func TestElementHandleQuery(t *testing.T) {
+	t.Parallel()
+
+	p := newTestBrowser(t).NewPage(nil)
+	p.SetContent(`<div id="foo">hello</div>`, nil)
+
+	element, err := p.Query("bar")
+
+	require.NoError(t, err)
+	require.Nil(t, element)
+}