diff --git a/lib/logstorage/pipe_fields_test.go b/lib/logstorage/pipe_fields_test.go
index a7b1e792b..000072081 100644
--- a/lib/logstorage/pipe_fields_test.go
+++ b/lib/logstorage/pipe_fields_test.go
@@ -4,6 +4,122 @@ import (
 	"testing"
 )
 
+func TestParsePipeFieldsSuccess(t *testing.T) {
+	f := func(pipeStr string) {
+		t.Helper()
+		expectParsePipeSuccess(t, pipeStr)
+	}
+
+	f(`fields *`)
+	f(`fields f1`)
+	f(`fields f1, f2, f3`)
+}
+
+func TestParsePipeFieldsFailure(t *testing.T) {
+	f := func(pipeStr string) {
+		t.Helper()
+		expectParsePipeFailure(t, pipeStr)
+	}
+
+	f(`fields`)
+	f(`fields x y`)
+}
+
+func TestPipeFields(t *testing.T) {
+	f := func(pipeStr string, rows, rowsExpected [][]Field) {
+		t.Helper()
+		expectPipeResults(t, pipeStr, rows, rowsExpected)
+	}
+
+	// single row, star
+	f("fields *", [][]Field{
+		{
+			{"_msg", `{"foo":"bar"}`},
+			{"a", `test`},
+		},
+	}, [][]Field{
+		{
+			{"_msg", `{"foo":"bar"}`},
+			{"a", `test`},
+		},
+	})
+
+	// single row, leave existing field
+	f("fields a", [][]Field{
+		{
+			{"_msg", `{"foo":"bar"}`},
+			{"a", `test`},
+		},
+	}, [][]Field{
+		{
+			{"a", `test`},
+		},
+	})
+
+	// single row, mention existing field multiple times
+	f("fileds a, a", [][]Field{
+		{
+			{"_msg", `{"foo":"bar"}`},
+			{"a", `test`},
+		},
+	}, [][]Field{
+		{
+			{"a", `test`},
+		},
+	})
+
+	// mention non-existing fields
+	f("fields foo, a, bar", [][]Field{
+		{
+			{"_msg", `{"foo":"bar"}`},
+			{"a", `test`},
+		},
+	}, [][]Field{
+		{
+			{"foo", ""},
+			{"bar", ""},
+			{"a", `test`},
+		},
+	})
+
+	// Multiple rows
+	f("fields a, b", [][]Field{
+		{
+			{"_msg", `{"foo":"bar"}`},
+			{"a", `test`},
+		},
+		{
+			{"a", `foobar`},
+		},
+		{
+			{"b", `baz`},
+			{"c", "d"},
+			{"e", "afdf"},
+		},
+		{
+			{"c", "dss"},
+			{"b", "df"},
+		},
+	}, [][]Field{
+		{
+			{"a", `test`},
+			{"b", `test`},
+		},
+		{
+			{"a", `foobar`},
+			{"b", `foobar`},
+		},
+		{
+			{"a", ""},
+			{"b", ""},
+		},
+		{
+			{"a", ""},
+			{"b", "df"},
+		},
+	})
+}
+
 func TestPipeFieldsUpdateNeededFields(t *testing.T) {
 	f := func(s, neededFields, unneededFields, neededFieldsExpected, unneededFieldsExpected string) {
 		t.Helper()