json2go/json2go_test.go (view raw)
| 1 | package json2go |
| 2 | |
| 3 | import ( |
| 4 | "errors" |
| 5 | "fmt" |
| 6 | "reflect" |
| 7 | "strings" |
| 8 | "testing" |
| 9 | ) |
| 10 | |
| 11 | func field(indentLvl int, name, type_ string, json_ ...string) string { |
| 12 | indent := strings.Repeat("\t", indentLvl) |
| 13 | if strings.Contains(type_, "struct") { |
| 14 | return fmt.Sprintf("\n%s%s %s", indent, name, type_) |
| 15 | } |
| 16 | |
| 17 | tag := strings.ToLower(name) |
| 18 | if len(json_) == 1 { |
| 19 | tag = json_[0] |
| 20 | } |
| 21 | return fmt.Sprintf("\n%s%s %s `json:\"%s\"`", indent, name, type_, tag) |
| 22 | } |
| 23 | |
| 24 | func TestTransformer_Transform(t *testing.T) { |
| 25 | tests := map[string]struct { |
| 26 | input string |
| 27 | output string |
| 28 | structName string |
| 29 | err error |
| 30 | }{ |
| 31 | "simple object": { |
| 32 | input: `{"name": "Olex", "active": true, "age": 420}`, |
| 33 | output: "type Out struct {" + |
| 34 | field(1, "Active", "bool") + |
| 35 | field(1, "Age", "int") + |
| 36 | field(1, "Name", "string") + |
| 37 | "\n}", |
| 38 | }, |
| 39 | "invalid json": { |
| 40 | err: ErrInvalidJSON, |
| 41 | input: `{"invalid":json}`, |
| 42 | }, |
| 43 | "invalid struct name, starts with number": { |
| 44 | err: ErrInvalidStructName, |
| 45 | structName: "1Name", |
| 46 | }, |
| 47 | "invalid struct name, has space": { |
| 48 | err: ErrInvalidStructName, |
| 49 | structName: "Name Name2", |
| 50 | }, |
| 51 | "invalid struct name, has non letter/number": { |
| 52 | err: ErrInvalidStructName, |
| 53 | structName: "Name$", |
| 54 | }, |
| 55 | "snake_case to CamelCase": { |
| 56 | input: `{"first_name": "Bob", "last_name": "Bobberson"}`, |
| 57 | output: "type Out struct {" + |
| 58 | field(1, "FirstName", "string", "first_name") + |
| 59 | field(1, "LastName", "string", "last_name") + |
| 60 | "\n}", |
| 61 | }, |
| 62 | "nested object and array": { |
| 63 | input: `{"user": {"name": "Alice", "score": 95.5}, "tags": ["go", "json"]}`, |
| 64 | output: "type Out struct {" + |
| 65 | field(1, "Tags", "[]string") + |
| 66 | field(1, "User", "struct {") + |
| 67 | field(2, "Name", "string") + |
| 68 | field(2, "Score", "float64") + |
| 69 | "\n\t} `json:\"user\"`" + |
| 70 | "\n}", |
| 71 | }, |
| 72 | "empty nested object": { |
| 73 | input: `{"user": {}}`, |
| 74 | output: "type Out struct {" + |
| 75 | field(1, "User", "struct {") + |
| 76 | "\n\t} `json:\"user\"`" + |
| 77 | "\n}", |
| 78 | }, |
| 79 | "array of object": { |
| 80 | input: `[{"name": "John"}, {"name": "Jane"}]`, |
| 81 | output: "type Out []struct {" + |
| 82 | field(1, "Name", "string") + |
| 83 | "\n}", |
| 84 | }, |
| 85 | "empty array": { |
| 86 | input: `{"items": []}`, |
| 87 | output: "type Out struct {" + |
| 88 | field(1, "Items", "[]any") + |
| 89 | "\n}", |
| 90 | }, |
| 91 | "null": { |
| 92 | input: `{"item": null}`, |
| 93 | output: `type Out struct {` + |
| 94 | field(1, "Item", "any") + |
| 95 | "\n}", |
| 96 | }, |
| 97 | "numbers": { |
| 98 | input: `{"pos": 123, "neg": -321, "float": 420.69}`, |
| 99 | output: "type Out struct {" + |
| 100 | field(1, "Float", "float64") + |
| 101 | field(1, "Neg", "int") + |
| 102 | field(1, "Pos", "int") + |
| 103 | "\n}", |
| 104 | }, |
| 105 | } |
| 106 | |
| 107 | trans := NewTransformer() |
| 108 | for tname, tt := range tests { |
| 109 | t.Run(tname, func(t *testing.T) { |
| 110 | sn := "Out" |
| 111 | if tt.structName != "" { |
| 112 | sn = tt.structName |
| 113 | } |
| 114 | |
| 115 | result, err := trans.Transform(sn, tt.input) |
| 116 | assertEqualErr(t, tt.err, err) |
| 117 | assertEqual(t, tt.output, result) |
| 118 | }) |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | func assertEqualErr(t *testing.T, expected, actual error) { |
| 123 | t.Helper() |
| 124 | if expected == nil && actual == nil { |
| 125 | return |
| 126 | } |
| 127 | |
| 128 | if expected == nil || actual == nil { |
| 129 | t.Errorf("expected: %v, got: %v", expected, actual) |
| 130 | return |
| 131 | } |
| 132 | |
| 133 | if !errors.Is(actual, expected) { |
| 134 | t.Errorf("expected error: %v, got: %v", expected, actual) |
| 135 | } |
| 136 | } |
| 137 | |
| 138 | func assertEqual[T any](t *testing.T, expected, actual T) { |
| 139 | t.Helper() |
| 140 | if !reflect.DeepEqual(expected, actual) { |
| 141 | t.Errorf("expected: %v, got: %v\n", expected, actual) |
| 142 | } |
| 143 | } |