test/formatters/
json.rs

1use std::borrow::Cow;
2use std::io;
3use std::io::prelude::Write;
4
5use super::OutputFormatter;
6use crate::console::{ConsoleTestDiscoveryState, ConsoleTestState, OutputLocation};
7use crate::test_result::TestResult;
8use crate::time;
9use crate::types::TestDesc;
10
11pub(crate) struct JsonFormatter<T> {
12    out: OutputLocation<T>,
13}
14
15impl<T: Write> JsonFormatter<T> {
16    pub(crate) fn new(out: OutputLocation<T>) -> Self {
17        Self { out }
18    }
19
20    fn writeln_message(&mut self, s: &str) -> io::Result<()> {
21        // self.out will take a lock, but that lock is released when write_all returns. This
22        // results in a race condition and json output may not end with a new line. We avoid this
23        // by issuing `write_all` calls line-by-line.
24        assert_eq!(s.chars().last(), Some('\n'));
25
26        self.out.write_all(s.as_ref())
27    }
28
29    fn write_event(
30        &mut self,
31        ty: &str,
32        name: &str,
33        event: &str,
34        exec_time: Option<&time::TestExecTime>,
35        stdout: Option<Cow<'_, str>>,
36        extra: Option<&str>,
37    ) -> io::Result<()> {
38        // A doc test's name includes a filename which must be escaped for correct json.
39        let name = EscapedString(name);
40        let exec_time_json = if let Some(exec_time) = exec_time {
41            format!(r#", "exec_time": {}"#, exec_time.0.as_secs_f64())
42        } else {
43            String::from("")
44        };
45        let stdout_json = if let Some(stdout) = stdout {
46            format!(r#", "stdout": "{}""#, EscapedString(stdout))
47        } else {
48            String::from("")
49        };
50        let extra_json =
51            if let Some(extra) = extra { format!(r#", {extra}"#) } else { String::from("") };
52        let newline = "\n";
53
54        self.writeln_message(&format!(
55                r#"{{ "type": "{ty}", "name": "{name}", "event": "{event}"{exec_time_json}{stdout_json}{extra_json} }}{newline}"#))
56    }
57}
58
59impl<T: Write> OutputFormatter for JsonFormatter<T> {
60    fn write_discovery_start(&mut self) -> io::Result<()> {
61        self.writeln_message(concat!(r#"{ "type": "suite", "event": "discovery" }"#, "\n"))
62    }
63
64    fn write_test_discovered(&mut self, desc: &TestDesc, test_type: &str) -> io::Result<()> {
65        let TestDesc {
66            name,
67            ignore,
68            ignore_message,
69            source_file,
70            start_line,
71            start_col,
72            end_line,
73            end_col,
74            ..
75        } = desc;
76
77        let name = EscapedString(name.as_slice());
78        let ignore_message = ignore_message.unwrap_or("");
79        let source_path = EscapedString(source_file);
80        let newline = "\n";
81
82        self.writeln_message(&format!(
83            r#"{{ "type": "{test_type}", "event": "discovered", "name": "{name}", "ignore": {ignore}, "ignore_message": "{ignore_message}", "source_path": "{source_path}", "start_line": {start_line}, "start_col": {start_col}, "end_line": {end_line}, "end_col": {end_col} }}{newline}"#
84        ))
85    }
86
87    fn write_discovery_finish(&mut self, state: &ConsoleTestDiscoveryState) -> io::Result<()> {
88        let ConsoleTestDiscoveryState { tests, benchmarks, ignored, .. } = state;
89
90        let total = tests + benchmarks;
91        let newline = "\n";
92        self.writeln_message(&format!(
93            r#"{{ "type": "suite", "event": "completed", "tests": {tests}, "benchmarks": {benchmarks}, "total": {total}, "ignored": {ignored} }}{newline}"#
94            ))
95    }
96
97    fn write_run_start(&mut self, test_count: usize, shuffle_seed: Option<u64>) -> io::Result<()> {
98        let shuffle_seed_json = if let Some(shuffle_seed) = shuffle_seed {
99            format!(r#", "shuffle_seed": {shuffle_seed}"#)
100        } else {
101            String::new()
102        };
103        let newline = "\n";
104        self.writeln_message(&format!(
105            r#"{{ "type": "suite", "event": "started", "test_count": {test_count}{shuffle_seed_json} }}{newline}"#
106            ))
107    }
108
109    fn write_test_start(&mut self, desc: &TestDesc) -> io::Result<()> {
110        let name = EscapedString(desc.name.as_slice());
111        let newline = "\n";
112        self.writeln_message(&format!(
113            r#"{{ "type": "test", "event": "started", "name": "{name}" }}{newline}"#
114        ))
115    }
116
117    fn write_result(
118        &mut self,
119        desc: &TestDesc,
120        result: &TestResult,
121        exec_time: Option<&time::TestExecTime>,
122        stdout: &[u8],
123        state: &ConsoleTestState,
124    ) -> io::Result<()> {
125        let display_stdout = state.options.display_output || *result != TestResult::TrOk;
126        let stdout = if display_stdout && !stdout.is_empty() {
127            Some(String::from_utf8_lossy(stdout))
128        } else {
129            None
130        };
131        match *result {
132            TestResult::TrOk => {
133                self.write_event("test", desc.name.as_slice(), "ok", exec_time, stdout, None)
134            }
135
136            TestResult::TrFailed => {
137                self.write_event("test", desc.name.as_slice(), "failed", exec_time, stdout, None)
138            }
139
140            TestResult::TrTimedFail => self.write_event(
141                "test",
142                desc.name.as_slice(),
143                "failed",
144                exec_time,
145                stdout,
146                Some(r#""reason": "time limit exceeded""#),
147            ),
148
149            TestResult::TrFailedMsg(ref m) => self.write_event(
150                "test",
151                desc.name.as_slice(),
152                "failed",
153                exec_time,
154                stdout,
155                Some(&*format!(r#""message": "{}""#, EscapedString(m))),
156            ),
157
158            TestResult::TrIgnored => self.write_event(
159                "test",
160                desc.name.as_slice(),
161                "ignored",
162                exec_time,
163                stdout,
164                desc.ignore_message
165                    .map(|msg| format!(r#""message": "{}""#, EscapedString(msg)))
166                    .as_deref(),
167            ),
168
169            TestResult::TrBench(ref bs) => {
170                let median = bs.ns_iter_summ.median;
171                let deviation = bs.ns_iter_summ.max - bs.ns_iter_summ.min;
172
173                let mbps = if bs.mb_s == 0 {
174                    String::new()
175                } else {
176                    format!(r#", "mib_per_second": {}"#, bs.mb_s)
177                };
178                let name = EscapedString(desc.name.as_slice());
179
180                self.writeln_message(&format!(
181                    "{{ \"type\": \"bench\", \
182                     \"name\": \"{name}\", \
183                     \"median\": {median}, \
184                     \"deviation\": {deviation}{mbps} }}\n",
185                ))
186            }
187        }
188    }
189
190    fn write_timeout(&mut self, desc: &TestDesc) -> io::Result<()> {
191        let name = EscapedString(desc.name.as_slice());
192        let newline = "\n";
193        self.writeln_message(&format!(
194            r#"{{ "type": "test", "event": "timeout", "name": "{name}" }}{newline}"#,
195        ))
196    }
197
198    fn write_run_finish(&mut self, state: &ConsoleTestState) -> io::Result<bool> {
199        let event = if state.failed == 0 { "ok" } else { "failed" };
200        let passed = state.passed;
201        let failed = state.failed;
202        let ignored = state.ignored;
203        let measured = state.measured;
204        let filtered_out = state.filtered_out;
205        let exec_time_json = if let Some(ref exec_time) = state.exec_time {
206            format!(r#", "exec_time": {}"#, exec_time.0.as_secs_f64())
207        } else {
208            String::from("")
209        };
210        let newline = "\n";
211
212        self.writeln_message(&format!(
213            r#"{{ "type": "suite", "event": "{event}", "passed": {passed}, "failed": {failed}, "ignored": {ignored}, "measured": {measured}, "filtered_out": {filtered_out}{exec_time_json} }}{newline}"#
214        ))?;
215
216        Ok(state.failed == 0)
217    }
218}
219
220/// A formatting utility used to print strings with characters in need of escaping.
221/// Base code taken form `libserialize::json::escape_str`
222struct EscapedString<S: AsRef<str>>(S);
223
224impl<S: AsRef<str>> std::fmt::Display for EscapedString<S> {
225    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> ::std::fmt::Result {
226        let mut start = 0;
227
228        for (i, byte) in self.0.as_ref().bytes().enumerate() {
229            let escaped = match byte {
230                b'"' => "\\\"",
231                b'\\' => "\\\\",
232                b'\x00' => "\\u0000",
233                b'\x01' => "\\u0001",
234                b'\x02' => "\\u0002",
235                b'\x03' => "\\u0003",
236                b'\x04' => "\\u0004",
237                b'\x05' => "\\u0005",
238                b'\x06' => "\\u0006",
239                b'\x07' => "\\u0007",
240                b'\x08' => "\\b",
241                b'\t' => "\\t",
242                b'\n' => "\\n",
243                b'\x0b' => "\\u000b",
244                b'\x0c' => "\\f",
245                b'\r' => "\\r",
246                b'\x0e' => "\\u000e",
247                b'\x0f' => "\\u000f",
248                b'\x10' => "\\u0010",
249                b'\x11' => "\\u0011",
250                b'\x12' => "\\u0012",
251                b'\x13' => "\\u0013",
252                b'\x14' => "\\u0014",
253                b'\x15' => "\\u0015",
254                b'\x16' => "\\u0016",
255                b'\x17' => "\\u0017",
256                b'\x18' => "\\u0018",
257                b'\x19' => "\\u0019",
258                b'\x1a' => "\\u001a",
259                b'\x1b' => "\\u001b",
260                b'\x1c' => "\\u001c",
261                b'\x1d' => "\\u001d",
262                b'\x1e' => "\\u001e",
263                b'\x1f' => "\\u001f",
264                b'\x7f' => "\\u007f",
265                _ => {
266                    continue;
267                }
268            };
269
270            if start < i {
271                f.write_str(&self.0.as_ref()[start..i])?;
272            }
273
274            f.write_str(escaped)?;
275
276            start = i + 1;
277        }
278
279        if start != self.0.as_ref().len() {
280            f.write_str(&self.0.as_ref()[start..])?;
281        }
282
283        Ok(())
284    }
285}