feat: tests for PFMERGE added

internal/tests/integration/commands/pfmerge_test.go

@@ -0,0 +1,88 @@
+package commands
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPfMerge(t *testing.T) {
+	exec, err := NewHTTPCommandExecutor()
+	if err != nil {
+		t.Fatal(err)
+	}
+	testCases := []TestCase{
+		{
+			Name: "PFMERGE multiple HyperLogLogs into a new one",
+			Commands: []HTTPCommand{
+				{Command: "PFADD", Body: []string{"hll1", "a", "b", "c"}},
+				{Command: "PFADD", Body: []string{"hll2", "c", "d", "e"}},
+				{Command: "PFADD", Body: []string{"hll3", "e", "f", "g"}},
+				{Command: "PFMERGE", Body: []string{"hll_merged", "hll1", "hll2", "hll3"}},
+				{Command: "PFCOUNT", Body: []string{"hll_merged"}},
+			},
+			Result: []TestCaseResult{
+				{Expected: "(integer) 1"},
+				{Expected: "(integer) 1"},
+				{Expected: "(integer) 1"},
+				{Expected: "OK"},
+				{Expected: "(integer) 7"},
+			},
+		},
+		{
+			Name: "PFMERGE overwrites existing destination key",
+			Commands: []HTTPCommand{
+				{Command: "PFADD", Body: []string{"hll_merged", "x", "y", "z"}},
+				{Command: "PFMERGE", Body: []string{"hll_merged", "hll1", "hll2", "hll3"}},
+				{Command: "PFCOUNT", Body: []string{"hll_merged"}},
+			},
+			Result: []TestCaseResult{
+				{Expected: "(integer) 1"},
+				{Expected: "OK"},
+				{Expected: "(integer) 10"},
+			},
+		},
+		{
+			Name: "PFMERGE with non-existent source key",
+			Commands: []HTTPCommand{
+
+				{Command: "PFMERGE", Body: []string{"hll_merged", "hll1", "hll2", "non_existent_key"}},
+				{Command: "PFCOUNT", Body: []string{"hll_merged"}},
+			},
+			Result: []TestCaseResult{
+				{Expected: "OK"},
+				{Expected: "(integer) 10"},
+			},
+		},
+		{
+			Name: "PFMERGE with wrong type of key",
+			Commands: []HTTPCommand{
+				{Command: "SET", Body: []string{"not_hyperLogLog", "some_value"}},
+				{Command: "PFMERGE", Body: []string{"hll_merged", "not_hyperLogLog"}},
+			},
+			Result: []TestCaseResult{
+				{Expected: "OK"},
+				{ErrorExpected: true, Expected: "(error) WRONGTYPE Key is not a valid HyperLogLog string value."},
+			},
+		},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.Name, func(t *testing.T) {
+			for i, cmd := range tc.Commands {
+				response, err := exec.FireCommand(cmd)
+				if err != nil {
+					t.Logf("error in executing command: %s - %v", cmd.Command, err)
+				}
+
+				result := tc.Result[i]
+				if result.ErrorExpected {
+					assert.NotNil(t, err)
+					assert.Equal(t, result.Expected, err.Error())
+				} else {
+					assert.Equal(t, result.Expected, response)
+				}
+			}
+		})
+	}
+
+}