Implement IIF function; Fix empty object select

parsers/nosql/misc_test.go

@@ -163,4 +163,27 @@ func Test_Parse(t *testing.T) {
 			},
 		)
 	})
+
+	t.Run("Should parse IIF function", func(t *testing.T) {
+		testQueryParse(
+			t,
+			`SELECT IIF(true, c.pk, c.id) FROM c`,
+			parsers.SelectStmt{
+				SelectItems: []parsers.SelectItem{
+					{
+						Type: parsers.SelectItemTypeFunctionCall,
+						Value: parsers.FunctionCall{
+							Type: parsers.FunctionCallIif,
+							Arguments: []interface{}{
+								testutils.SelectItem_Constant_Bool(true),
+								testutils.SelectItem_Path("c", "pk"),
+								testutils.SelectItem_Path("c", "id"),
+							},
+						},
+					},
+				},
+				Table: parsers.Table{SelectItem: testutils.SelectItem_Path("c")},
+			},
+		)
+	})
 }

parsers/nosql/nosql.peg

@@ -289,6 +289,11 @@ SelectArray <- "[" ws columns:ColumnList ws "]" {
 
 SelectObject <- "{" ws field:SelectObjectField ws other_fields:(ws "," ws coll:SelectObjectField {return coll, nil })* ws "}" {
     return makeSelectObject(field, other_fields)
+} / "{" ws "}" {
+    return parsers.SelectItem{
+		SelectItems: []parsers.SelectItem{},
+		Type:        parsers.SelectItemTypeObject,
+	}, nil
 }
 
 SelectObjectField <- name:(Identifier / "\"" key:Identifier "\"" { return key, nil }) ws ":" ws selectItem:SelectItem {
@@ -442,6 +447,7 @@ BooleanLiteral <- ("true"i / "false"i) {
 FunctionCall <- StringFunctions
     / TypeCheckingFunctions
     / ArrayFunctions
+    / ConditionalFunctions
     / InFunction
     / AggregateFunctions
     / MathFunctions
@@ -489,6 +495,8 @@ ArrayFunctions <- ArrayConcatExpression
     / SetIntersectExpression
     / SetUnionExpression
 
+ConditionalFunctions <- IifExpression
+
 MathFunctions <- MathAbsExpression
     / MathAcosExpression
     / MathAsinExpression
@@ -681,6 +689,10 @@ SetUnionExpression <- "SetUnion"i ws "(" ws set1:SelectItem ws "," ws set2:Selec
     return createFunctionCall(parsers.FunctionCallSetUnion, []interface{}{set1, set2})
 }
 
+IifExpression <- "IIF"i ws "(" ws condition:SelectItem ws "," ws trueValue:SelectItem ws "," ws falseValue:SelectItem ws ")" {
+    return createFunctionCall(parsers.FunctionCallIif, []interface{}{condition, trueValue, falseValue})
+}
+
 MathAbsExpression <- "ABS"i ws "(" ws ex:SelectItem ws ")" { return createFunctionCall(parsers.FunctionCallMathAbs, []interface{}{ex}) }
 MathAcosExpression <- "ACOS"i ws "(" ws ex:SelectItem ws ")" { return createFunctionCall(parsers.FunctionCallMathAcos, []interface{}{ex}) }
 MathAsinExpression <- "ASIN"i ws "(" ws ex:SelectItem ws ")" { return createFunctionCall(parsers.FunctionCallMathAsin, []interface{}{ex}) }

parsers/nosql/select_test.go

@@ -178,4 +178,21 @@ func Test_Parse_Select(t *testing.T) {
 			},
 		)
 	})
+
+	t.Run("Should parse SELECT empty object", func(t *testing.T) {
+		testQueryParse(
+			t,
+			`SELECT {} AS obj FROM c`,
+			parsers.SelectStmt{
+				SelectItems: []parsers.SelectItem{
+					{
+						Alias:       "obj",
+						Type:        parsers.SelectItemTypeObject,
+						SelectItems: []parsers.SelectItem{},
+					},
+				},
+				Table: parsers.Table{SelectItem: testutils.SelectItem_Path("c")},
+			},
+		)
+	})
 }