From 0cb03234f692c351c1bd7ee52c69da5740dde16c Mon Sep 17 00:00:00 2001
From: Christian Lappin <christian@tumblyhaus.com>
Date: Sat, 14 Nov 2026 14:53:31 -0500
Subject: [PATCH] Keep the download update test stable in Linux coverage

---
 Cargo.lock                         |  1 +
 crates/ui-egui/Cargo.toml          |  3 +++
 crates/ui-egui/tests/it/updates.rs | 25 +++++++++++++++++++++++++
 3 files changed, 29 insertions(+)

diff --git a/Cargo.lock b/Cargo.lock
index 2ad337ab20..b7596fa0f5 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5014,6 +5014,7 @@ dependencies = [
  "serde_json",
  "skrifa 0.44.0",
  "sys-locale",
+ "tempfile",
  "toml",
  "unicode-bidi",
  "wasm-bindgen",
diff --git a/crates/ui-egui/Cargo.toml b/crates/ui-egui/Cargo.toml
index 93d3a4c9ad..cca968360b 100644
--- a/crates/ui-egui/Cargo.toml
+++ b/crates/ui-egui/Cargo.toml
@@ -113,3 +113,6 @@ toml = "1"
 [target.'cfg(target_os = "macos")'.dev-dependencies]
 # Only synthetic attribute fixtures use xattr; product reads/writes use rustix.
 xattr = "1.6"
+
+[target.'cfg(target_os = "linux")'.dev-dependencies]
+tempfile = "3.27"
diff --git a/crates/ui-egui/tests/it/updates.rs b/crates/ui-egui/tests/it/updates.rs
index 61a0e03ee5..f6c6c03bd0 100644
--- a/crates/ui-egui/tests/it/updates.rs
+++ b/crates/ui-egui/tests/it/updates.rs
@@ -49,6 +49,31 @@ fn settle(h: &mut Harness<'static, PdfCraftApp>) {
 
 #[test]
 fn a_newer_release_is_offered_for_download() {
+    #[cfg(target_os = "linux")]
+    {
+        const FIXTURE: &str = "PDFCRAFT_TEST_UPDATE_DOWNLOAD_FIXTURE";
+        if craft_update::self_update::is_self_updating(&pdfcraft_ui_egui::UPDATE_APP) {
+            assert!(std::env::var_os(FIXTURE).is_none(), "the fixture must be detected as a Cargo build");
+            // nextest's extracted archive can omit Cargo's metadata. Give the child a
+            // private build directory with the marker the updater uses to identify it.
+            let current = std::env::current_exe().unwrap();
+            let build = tempfile::tempdir_in(current.parent().unwrap()).unwrap();
+            std::fs::write(build.path().join(".rustc_info.json"), "{}").unwrap();
+            let exe = build.path().join("update-download-test");
+            if std::fs::hard_link(&current, &exe).is_err() {
+                std::fs::copy(&current, &exe).unwrap();
+            }
+            let output = std::process::Command::new(exe)
+                .args(["--exact", "updates::a_newer_release_is_offered_for_download", "--nocapture"])
+                .env(FIXTURE, "1")
+                .env_remove(craft_update::self_update::DEV_VAR)
+                .output()
+                .unwrap();
+            assert!(output.status.success(), "{}\n{}", String::from_utf8_lossy(&output.stdout), String::from_utf8_lossy(&output.stderr));
+            assert!(String::from_utf8_lossy(&output.stdout).contains("1 passed"));
+            return;
+        }
+    }
     let mut h = harness(Ok(Some("v99.0.0")));
     h.state_mut().execute("help.check_updates");
     settle(&mut h);