feat(infra): add custom panic hook. Print backtrace and thread, error info on panic. (#75)

* Add custom panic hook. Print backtrace and thread, error info on panic.

* use sync_channel and SyncSender

* nit fixes and cleanup

* disable custom panic hook while running tests

* make separate errors.rs file and address other review comments

* improve panic message

* debug: does increasing time between snapshots make tests pass? (this is temporary)

* fix(tests): suspend before sending quit command

* fix(tests): add missing use

* style(format): commas are important apparently

* fix(tests): can we get away with reducing the QUIT suspense time?

* fix(tests): can we get away with 50?

Co-authored-by: Aram Drevekenin <aram@poor.dev>

1 files changed, 56 insertions, 0 deletions

diff --git a/src/errors.rs b/src/errors.rs
new file mode 100644
index 00000000..26e0010d
--- /dev/null
+++ b/src/errors.rs
@@ -0,0 +1,56 @@
+use crate::AppInstruction;
+use backtrace::Backtrace;
+use std::panic::PanicInfo;
+use std::sync::mpsc::SyncSender;
+use std::{process, thread};
+
+pub fn handle_panic(info: &PanicInfo<'_>, send_app_instructions: &SyncSender<AppInstruction>) {
+    let backtrace = Backtrace::new();
+    let thread = thread::current();
+    let thread = thread.name().unwrap_or("unnamed");
+
+    let msg = match info.payload().downcast_ref::<&'static str>() {
+        Some(s) => Some(*s),
+        None => info.payload().downcast_ref::<String>().map(|s| &**s),
+    };
+
+    let backtrace = match (info.location(), msg) {
+        (Some(location), Some(msg)) => {
+            format!(
+                "\nthread '{}' panicked at '{}': {}:{}\n{:?}",
+                thread,
+                msg,
+                location.file(),
+                location.line(),
+                backtrace
+            )
+        }
+        (Some(location), None) => {
+            format!(
+                "\nthread '{}' panicked: {}:{}\n{:?}",
+                thread,
+                location.file(),
+                location.line(),
+                backtrace
+            )
+        }
+        (None, Some(msg)) => {
+            format!(
+                "\nthread '{}' panicked at '{}'\n{:?}",
+                thread, msg, backtrace
+            )
+        }
+        (None, None) => {
+            format!("\nthread '{}' panicked\n{:?}", thread, backtrace)
+        }
+    };
+
+    if thread == "main" {
+        println!("{}", backtrace);
+        process::exit(1);
+    } else {
+        send_app_instructions
+            .send(AppInstruction::Error(backtrace))
+            .unwrap();
+    }
+}