fromjson_runner_test.go RawHistoryFolder

1// SPDX-License-Identifier: MIT
2
3package expr
4
5import (
6	"encoding/json"
7	"os"
8	"strings"
9	"testing"
10)
11
12type fromJSONCase struct {
13	In  string `json:"in"`
14	OK  bool   `json:"ok"`
15	Out string `json:"out"`
16}
17
18func loadFromJSONCases(tb testing.TB) []fromJSONCase {
19	tb.Helper()
20	data, err := os.ReadFile("testdata/fromjson_cases.json")
21	if err != nil {
22		tb.Fatal(err)
23	}
24	var cs []fromJSONCase
25	if err := json.Unmarshal(data, &cs); err != nil {
26		tb.Fatal(err)
27	}
28	return cs
29}
30
31// unportedJSON reports whether the input uses something of Json.NET that is not
32// ported: comments and constructors. The runner accepts them, this package
33// fails on them (see PORTING.md).
34func unportedJSON(s string) bool {
35	return strings.Contains(s, "/*") || strings.Contains(s, "//") || strings.Contains(s, "new ") || strings.Contains(s, "/")
36}
37
38// TestFromJSONMatchesRunner replays testdata/fromjson_cases.json, the answers
39// of the runner's fromJSON (gen/runner/fromjson_cases.mjs) on hand-picked and
40// mutated JSON-like texts: it must accept exactly the same texts and give the
41// same toJSON, except where the text could hold a comment or constructor.
42func TestFromJSONMatchesRunner(t *testing.T) {
43	cases := loadFromJSONCases(t)
44	bad, skipped := 0, 0
45	for _, c := range cases {
46		v, err := FromJSON([]byte(c.In))
47		if err == nil && strings.TrimFunc(c.In, isNetSpace) == "" {
48			err = os.ErrInvalid // fromJSON() rejects blank input before reading
49		}
50		gotOK := err == nil
51		if gotOK != c.OK || (gotOK && ToJSON(v) != c.Out) {
52			if unportedJSON(c.In) {
53				skipped++
54				continue
55			}
56			bad++
57			if bad <= 25 {
58				t.Errorf("FromJSON(%q): ok=%v out=%q (%v); runner ok=%v out=%q", c.In, gotOK, func() string {
59					if v != nil {
60						return ToJSON(v)
61					}
62					return ""
63				}(), err, c.OK, c.Out)
64			}
65		}
66	}
67	t.Logf("%d cases, %d with comments, slashes or constructors skipped, %d mismatches", len(cases), skipped, bad)
68}