canic_testkit/pic/
startup.rs

1use std::{any::Any, panic::catch_unwind};
2
3use pocket_ic::PocketIcBuilder;
4
5use super::Pic;
6
7///
8/// PicStartError
9///
10
11#[derive(Debug, Eq, PartialEq)]
12pub enum PicStartError {
13    BinaryUnavailable { message: String },
14    BinaryInvalid { message: String },
15    DownloadFailed { message: String },
16    ServerStartFailed { message: String },
17    StartupTimedOut { message: String },
18    Panic { message: String },
19}
20
21pub(super) fn try_build_pic(builder: PocketIcBuilder) -> Result<Pic, PicStartError> {
22    let build = catch_unwind(|| builder.build());
23
24    match build {
25        Ok(inner) => Ok(Pic { inner }),
26        Err(payload) => Err(classify_pic_start_panic(payload)),
27    }
28}
29
30impl std::fmt::Display for PicStartError {
31    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
32        match self {
33            Self::BinaryUnavailable { message }
34            | Self::BinaryInvalid { message }
35            | Self::DownloadFailed { message }
36            | Self::ServerStartFailed { message }
37            | Self::StartupTimedOut { message }
38            | Self::Panic { message } => f.write_str(message),
39        }
40    }
41}
42
43impl std::error::Error for PicStartError {}
44
45// Extract a stable string message from one panic payload.
46pub(super) fn panic_payload_to_string(payload: &(dyn Any + Send)) -> String {
47    if let Some(message) = payload.downcast_ref::<String>() {
48        return message.clone();
49    }
50    if let Some(message) = payload.downcast_ref::<&'static str>() {
51        return (*message).to_string();
52    }
53
54    "non-string panic payload".to_string()
55}
56
57// Classify one PocketIC startup panic into a typed public error.
58fn classify_pic_start_panic(payload: Box<dyn Any + Send>) -> PicStartError {
59    let message = panic_payload_to_string(payload.as_ref());
60
61    if message.starts_with("Failed to validate PocketIC server binary") {
62        if message.contains("No such file or directory") || message.contains("os error 2") {
63            return PicStartError::BinaryUnavailable { message };
64        }
65
66        return PicStartError::BinaryInvalid { message };
67    }
68
69    if message.starts_with("Failed to download PocketIC server")
70        || message.starts_with("Failed to write PocketIC server binary")
71    {
72        return PicStartError::DownloadFailed { message };
73    }
74
75    if message.starts_with("Failed to start PocketIC binary")
76        || message.starts_with("Failed to create PocketIC server directory")
77    {
78        return PicStartError::ServerStartFailed { message };
79    }
80
81    if message.starts_with("Timed out waiting for PocketIC server being available") {
82        return PicStartError::StartupTimedOut { message };
83    }
84
85    PicStartError::Panic { message }
86}
87
88#[cfg(test)]
89mod tests {
90    use super::{PicStartError, classify_pic_start_panic};
91
92    #[test]
93    fn pic_start_error_classifies_missing_binary() {
94        let error = classify_pic_start_panic(Box::new(
95            "Failed to validate PocketIC server binary `/tmp/pocket-ic`: `No such file or directory (os error 2)`.".to_string(),
96        ));
97
98        assert!(matches!(error, PicStartError::BinaryUnavailable { .. }));
99    }
100
101    #[test]
102    fn pic_start_error_classifies_failed_spawn() {
103        let error = classify_pic_start_panic(Box::new(
104            "Failed to start PocketIC binary (/tmp/pocket-ic)".to_string(),
105        ));
106
107        assert!(matches!(error, PicStartError::ServerStartFailed { .. }));
108    }
109}
canic_testkit/pic/startup.rs

canic_testkit/pic/
startup.rs
