Deal with subsecond precision differents in db tests.

Apparently some environments roundtrip datetimes in Postgres
with different precision.

tests/db/jobs.rs

@@ -1,4 +1,5 @@
 use super::run_test;
+use crate::assert_datetime_approx_equal;
 use serde_json::json;
 
 #[test]
@@ -22,13 +23,13 @@ fn jobs() {
         let jobs = connection.get_jobs_to_execute().await.unwrap();
         assert_eq!(jobs.len(), 2);
         assert_eq!(jobs[0].name, "sample_job1");
-        assert_eq!(jobs[0].scheduled_at, past);
+        assert_datetime_approx_equal(&jobs[0].scheduled_at, &past);
         assert_eq!(jobs[0].metadata, json! {{"foo": 123}});
         assert_eq!(jobs[0].executed_at, None);
         assert_eq!(jobs[0].error_message, None);
 
         assert_eq!(jobs[1].name, "sample_job2");
-        assert_eq!(jobs[1].scheduled_at, past);
+        assert_datetime_approx_equal(&jobs[1].scheduled_at, &past);
         assert_eq!(jobs[1].metadata, json! {{}});
         assert_eq!(jobs[1].executed_at, None);
         assert_eq!(jobs[1].error_message, None);

tests/db/notification.rs

@@ -1,4 +1,5 @@
 use super::run_test;
+use crate::assert_datetime_approx_equal;
 use std::num::NonZeroUsize;
 use triagebot::db::notifications::{Identifier, Notification};
 
@@ -63,7 +64,7 @@ fn notification() {
             notifications[0].short_description.as_deref(),
             Some("Comment on some issue")
         );
-        assert_eq!(notifications[0].time, now);
+        assert_datetime_approx_equal(&notifications[0].time, &now);
         assert_eq!(notifications[0].metadata, None);
 
         assert_eq!(
@@ -78,7 +79,7 @@ fn notification() {
             notifications[1].short_description.as_deref(),
             Some("Comment on some issue")
         );
-        assert_eq!(notifications[1].time, now);
+        assert_datetime_approx_equal(&notifications[1].time, &now);
         assert_eq!(notifications[1].metadata, None);
 
         let notifications = connection.get_notifications("weihanglo").await.unwrap();
@@ -95,7 +96,7 @@ fn notification() {
             notifications[0].short_description.as_deref(),
             Some("Comment on some issue")
         );
-        assert_eq!(notifications[0].time, now);
+        assert_datetime_approx_equal(&notifications[0].time, &now);
         assert_eq!(notifications[0].metadata, None);
 
         let notifications = connection.get_notifications("octocat").await.unwrap();

tests/db/rustc_commits.rs

@@ -1,4 +1,5 @@
 use super::run_test;
+use crate::assert_datetime_approx_equal;
 use triagebot::db::Commit;
 
 #[test]
@@ -72,15 +73,15 @@ fn rustc_commits() {
             commits[0].parent_sha,
             "73f40197ecabf77ed59028af61739404eb60dd2e"
         );
-        assert_eq!(commits[0].time, now);
+        assert_datetime_approx_equal(&commits[0].time, &now);
         assert_eq!(commits[0].pr, Some(108228));
 
         assert_eq!(commits[1].sha, "73f40197ecabf77ed59028af61739404eb60dd2e");
         assert_eq!(
             commits[1].parent_sha,
             "fcdbd1c07f0b6c8e7d8bbd727c6ca69a1af8c7e9"
         );
-        assert_eq!(commits[1].time, now3);
+        assert_datetime_approx_equal(&commits[1].time, &now3);
         assert_eq!(commits[1].pr, Some(107772));
     });
 }

tests/testsuite.rs

@@ -16,6 +16,7 @@ mod db;
 mod github_client;
 mod server_test;
 
+use chrono::DateTime;
 use std::collections::HashMap;
 use std::io::{BufRead, BufReader, Read, Write};
 use std::net::TcpStream;
@@ -378,3 +379,19 @@ impl HttpServer {
         }
     }
 }
+
+/// Helper for comparing datetimes.
+///
+/// This helps ignore sub-second differences (which can happen when
+/// round-tripping through a database).
+pub fn assert_datetime_approx_equal<T, U>(a: &DateTime<T>, b: &DateTime<U>)
+where
+    T: chrono::TimeZone,
+    U: chrono::TimeZone,
+    <T as chrono::TimeZone>::Offset: std::fmt::Display,
+    <U as chrono::TimeZone>::Offset: std::fmt::Display,
+{
+    if a.timestamp() != b.timestamp() {
+        panic!("datetime differs {a} != {b}");
+    }
+}