test: Fix nil issue

Author: anubhav756

tests/mcp_tool.go

@@ -537,7 +537,7 @@ func RunMCPPostgresListSchemasTest(t *testing.T, ctx context.Context, pool *pgxp
 			name:           "invoke list_schemas with non-existent schema",
 			args:           map[string]any{"schema_name": "non_existent_schema"},
 			wantStatusCode: http.StatusOK,
-			want:           nil,
+			want:           []map[string]any{},
 		},
 	}
 	for _, tc := range invokeTcs {
@@ -555,7 +555,7 @@ func RunMCPPostgresListSchemasTest(t *testing.T, ctx context.Context, pool *pgxp
 			if mcpResp.Result.IsError {
 				t.Fatalf("list_schemas returned error result: %v", mcpResp.Result)
 			}
-			var gotObj []map[string]any
+			gotObj := []map[string]any{}
 			got := getMCPResultText(mcpResp)
 			if got != "null" {
 				gotObj, err = unmarshalMCPResult[map[string]any](got)
@@ -844,7 +844,7 @@ func RunMCPPostgresListTriggersTest(t *testing.T, ctx context.Context, pool *pgx
 			name:           "filter by non-existent trigger_name",
 			args:           map[string]any{"trigger_name": "non_existent_trigger"},
 			wantStatusCode: http.StatusOK,
-			want:           nil,
+			want:           []map[string]any{},
 		},
 	}
 	for _, tc := range invokeTcs {
@@ -950,7 +950,7 @@ func RunMCPPostgresListSequencesTest(t *testing.T, ctx context.Context, pool *pg
 			name:           "invoke list_sequences with non-existent sequence",
 			args:           map[string]any{"sequence_name": "non_existent_sequence"},
 			wantStatusCode: http.StatusOK,
-			want:           nil,
+			want:           []map[string]any{},
 		},
 	}
 	for _, tc := range invokeTcs {
@@ -968,7 +968,7 @@ func RunMCPPostgresListSequencesTest(t *testing.T, ctx context.Context, pool *pg
 			if mcpResp.Result.IsError {
 				t.Fatalf("list_sequences returned error result: %v", mcpResp.Result)
 			}
-			var gotObj []map[string]any
+			gotObj := []map[string]any{}
 			got := getMCPResultText(mcpResp)
 			if got != "null" {
 				gotObj, err = unmarshalMCPResult[map[string]any](got)
@@ -1086,7 +1086,7 @@ func RunMCPPostgresListIndexesTest(t *testing.T, ctx context.Context, pool *pgxp
 			name:           "invoke list_indexes with non-existent table",
 			args:           map[string]any{"table_name": "non_existent_table"},
 			wantStatusCode: http.StatusOK,
-			want:           nil,
+			want:           []map[string]any{},
 		},
 	}
 	for _, tc := range invokeTcs {
@@ -1105,7 +1105,7 @@ func RunMCPPostgresListIndexesTest(t *testing.T, ctx context.Context, pool *pgxp
 			if mcpResp.Result.IsError {
 				t.Fatalf("list_indexes returned error result: %v", mcpResp.Result)
 			}
-			var gotObj []map[string]any
+			gotObj := []map[string]any{}
 			for _, content := range mcpResp.Result.Content {
 				got := content.Text
 				t.Logf("list_indexes got: %s", got)