fix(windows): hide agent manifest curl windows

refs #1468

4 files changed, 47 insertions, 21 deletions

diff --git a/docs/next/CHANGELOG.md b/docs/next/CHANGELOG.md
index 3f75e127..2e83fd02 100644
--- a/docs/next/CHANGELOG.md
+++ b/docs/next/CHANGELOG.md
@@ -7,6 +7,7 @@
 - Added macOS support for the `HERDR_AGENT=<agent>` foreground-process hint, allowing agents hidden behind host-visible wrappers such as `nono` to use the named agent's screen manifest. (#679)
 
 ### Fixed
+- Background agent-detection manifest checks no longer flash curl console windows on Windows. (#1468)
 - Live handoff now preserves installed plugins and no longer lets the next plugin installation overwrite the existing registry. (#893)
 - `herdr wait agent-status` now returns `pane_not_found` promptly when its target pane closes instead of waiting for the full timeout. (#1439)
 
diff --git a/src/detect/manifest_update.rs b/src/detect/manifest_update.rs
index ac06ec97..02efa3bc 100644
--- a/src/detect/manifest_update.rs
+++ b/src/detect/manifest_update.rs
@@ -470,7 +470,9 @@ fn catalog_url() -> String {
 
 fn fetch_text(url: &str) -> Result<String, String> {
     let max_fetch_bytes = MAX_FETCH_BYTES.to_string();
-    let mut child = Command::new("curl")
+    let mut command = Command::new("curl");
+    crate::platform::configure_background_command(&mut command);
+    let mut child = command
         .args([
             "-sfL",
             "--retry",
diff --git a/src/platform/mod.rs b/src/platform/mod.rs
index 3583df5e..42b9e128 100644
--- a/src/platform/mod.rs
+++ b/src/platform/mod.rs
@@ -33,6 +33,13 @@ pub(crate) fn pane_custom_command_pty_builder(command: &str) -> portable_pty::Co
     pane_custom_command_pty_builder_platform(command)
 }
 
+pub(crate) fn configure_background_command(command: &mut std::process::Command) {
+    configure_background_command_platform(command);
+}
+
+#[cfg(not(windows))]
+fn configure_background_command_platform(_command: &mut std::process::Command) {}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub(crate) struct PlatformCapabilities {
     pub(crate) live_handoff: bool,
diff --git a/src/platform/windows.rs b/src/platform/windows.rs
index 209ec6d6..46c75141 100644
--- a/src/platform/windows.rs
+++ b/src/platform/windows.rs
@@ -28,8 +28,8 @@ use windows_sys::{
             Ole::CF_UNICODETEXT,
             Threading::{
                 GetCurrentProcess, GetExitCodeProcess, OpenProcess, TerminateProcess,
-                DETACHED_PROCESS, PROCESS_BASIC_INFORMATION, PROCESS_QUERY_LIMITED_INFORMATION,
-                PROCESS_VM_READ,
+                CREATE_NO_WINDOW, DETACHED_PROCESS, PROCESS_BASIC_INFORMATION,
+                PROCESS_QUERY_LIMITED_INFORMATION, PROCESS_VM_READ,
             },
         },
         UI::Shell::{CommandLineToArgvW, ShellExecuteW},
@@ -129,6 +129,12 @@ fn scrollback_editor_argv_with_env(
     Ok(argv)
 }
 
+pub(crate) fn configure_background_command_platform(command: &mut std::process::Command) {
+    use std::os::windows::process::CommandExt;
+
+    command.creation_flags(CREATE_NO_WINDOW);
+}
+
 pub fn detach_server_daemon_command(command: &mut std::process::Command) {
     use std::os::windows::process::CommandExt;
 
@@ -662,12 +668,16 @@ mod tests {
 
     use windows_sys::Win32::System::Console::{AllocConsole, FreeConsole, GetConsoleWindow};
 
-    const DETACHED_CONSOLE_TEST_CHILD_ENV: &str = "HERDR_TEST_DETACHED_CONSOLE_CHILD";
+    const CONSOLE_TEST_CHILD_ENV: &str = "HERDR_TEST_CONSOLE_CHILD_MODE";
 
     #[test]
-    fn server_daemon_command_does_not_inherit_console() {
-        if std::env::var_os(DETACHED_CONSOLE_TEST_CHILD_ENV).is_some() {
-            assert!(unsafe { GetConsoleWindow() }.is_null());
+    fn background_and_server_daemon_commands_do_not_have_consoles() {
+        if let Some(mode) = std::env::var_os(CONSOLE_TEST_CHILD_ENV) {
+            assert!(
+                unsafe { GetConsoleWindow() }.is_null(),
+                "{} child opened or inherited a console",
+                mode.to_string_lossy()
+            );
             return;
         }
 
@@ -679,26 +689,32 @@ mod tests {
         };
 
         let test_exe = std::env::current_exe().expect("resolve test executable");
-        let mut child = Command::new(test_exe);
-        child
-            .arg("server_daemon_command_does_not_inherit_console")
-            .env(DETACHED_CONSOLE_TEST_CHILD_ENV, "1")
-            .stdin(Stdio::null())
-            .stdout(Stdio::null())
-            .stderr(Stdio::null());
-        super::detach_server_daemon_command(&mut child);
+        let configurations: [(&str, fn(&mut Command)); 2] = [
+            ("background", super::configure_background_command_platform),
+            ("server daemon", super::detach_server_daemon_command),
+        ];
+        for (mode, configure) in configurations {
+            let mut child = Command::new(&test_exe);
+            child
+                .arg("background_and_server_daemon_commands_do_not_have_consoles")
+                .env(CONSOLE_TEST_CHILD_ENV, mode)
+                .stdin(Stdio::null())
+                .stdout(Stdio::null())
+                .stderr(Stdio::null());
+            configure(&mut child);
+
+            let status = child.status().expect("spawn console isolation test child");
+            assert!(
+                status.success(),
+                "{mode} child opened or inherited a console"
+            );
+        }
 
-        let status = child.status().expect("spawn detached test child");
         if allocated_console {
             unsafe {
                 FreeConsole();
             }
         }
-
-        assert!(
-            status.success(),
-            "detached child inherited the test console"
-        );
     }
 
     fn argv_strings(argv: &[std::ffi::OsString]) -> Vec<String> {