From a9720676ae0dd695b47fd95a9a81532d0e5253e8 Mon Sep 17 00:00:00 2001
From: zhom <2717306+zhom@users.noreply.github.com>
Date: Sun, 10 Aug 2025 04:14:43 +0400
Subject: [PATCH] test: cleanup

---
 src-tauri/src/app_auto_updater.rs    |  13 +-
 src-tauri/src/auto_updater.rs        |  82 ++++++---
 src-tauri/src/browser.rs             | 179 ++++++++++++------
 src-tauri/src/downloaded_browsers.rs |  32 +++-
 src-tauri/src/extraction.rs          | 266 +++++++++++++++++++++------
 src-tauri/src/geoip_downloader.rs    |  24 ++-
 src-tauri/src/group_manager.rs       | 252 +++++++++++++++++++++++++
 src-tauri/src/profile/manager.rs     | 131 ++++++++++++-
 src-tauri/src/profile_importer.rs    | 203 ++++++++++++++++++++
 src-tauri/src/proxy_manager.rs       |  68 ++++++-
 src-tauri/src/settings_manager.rs    | 210 +++++++++++++++++++++
 src-tauri/src/theme_detector.rs      | 101 +++++++++-
 src-tauri/src/version_updater.rs     | 143 ++++++++++++--
 13 files changed, 1526 insertions(+), 178 deletions(-)

diff --git a/src-tauri/src/app_auto_updater.rs b/src-tauri/src/app_auto_updater.rs
index 64faaad..d954f11 100644
--- a/src-tauri/src/app_auto_updater.rs
+++ b/src-tauri/src/app_auto_updater.rs
@@ -1717,16 +1717,21 @@ mod tests {
     let unsupported_file = temp_dir.join("test.rar");
 
     // Create a mock runtime to test the logic
-    let rt = tokio::runtime::Runtime::new().unwrap();
+    let rt = tokio::runtime::Runtime::new().expect("Failed to create tokio runtime");
 
     // This would fail because .rar is not supported, which proves
     // our method is using the Extractor logic
     let result = rt.block_on(async { updater.extract_update(&unsupported_file, &temp_dir).await });
 
     // Should fail with unsupported format error
-    assert!(result.is_err());
-    let error_msg = result.unwrap_err().to_string();
-    assert!(error_msg.contains("Unsupported archive format: rar"));
+    assert!(result.is_err(), "Unsupported format should return error");
+    let error_msg = result.expect_err("Should have error").to_string();
+    assert!(
+      error_msg.contains("Unsupported archive format: rar")
+        || error_msg.contains("unknown")
+        || error_msg.contains("unsupported"),
+      "Error should mention unsupported format, got: {error_msg}"
+    );
   }
 
   #[test]
diff --git a/src-tauri/src/auto_updater.rs b/src-tauri/src/auto_updater.rs
index 0bb381e..e366845 100644
--- a/src-tauri/src/auto_updater.rs
+++ b/src-tauri/src/auto_updater.rs
@@ -779,13 +779,15 @@ mod tests {
     let state_file = test_settings_manager
       .get_settings_dir()
       .join("auto_update_state.json");
-    std::fs::create_dir_all(test_settings_manager.get_settings_dir()).unwrap();
-    let json = serde_json::to_string_pretty(&state).unwrap();
-    std::fs::write(&state_file, json).unwrap();
+    std::fs::create_dir_all(test_settings_manager.get_settings_dir())
+      .expect("Failed to create settings directory");
+    let json = serde_json::to_string_pretty(&state).expect("Failed to serialize state");
+    std::fs::write(&state_file, json).expect("Failed to write state file");
 
     // Load state
-    let content = std::fs::read_to_string(&state_file).unwrap();
-    let loaded_state: AutoUpdateState = serde_json::from_str(&content).unwrap();
+    let content = std::fs::read_to_string(&state_file).expect("Failed to read state file");
+    let loaded_state: AutoUpdateState =
+      serde_json::from_str(&content).expect("Failed to deserialize state");
 
     assert_eq!(loaded_state.disabled_browsers.len(), 1);
     assert!(loaded_state.disabled_browsers.contains("firefox"));
@@ -823,11 +825,15 @@ mod tests {
     let state_file = test_settings_manager
       .get_settings_dir()
       .join("auto_update_state.json");
-    std::fs::create_dir_all(test_settings_manager.get_settings_dir()).unwrap();
+    std::fs::create_dir_all(test_settings_manager.get_settings_dir())
+      .expect("Failed to create settings directory");
 
     // Initially not disabled (empty state file means default state)
     let state = AutoUpdateState::default();
-    assert!(!state.disabled_browsers.contains("firefox"));
+    assert!(
+      !state.disabled_browsers.contains("firefox"),
+      "Firefox should not be disabled initially"
+    );
 
     // Start update (should disable)
     let mut state = AutoUpdateState::default();
@@ -835,27 +841,41 @@ mod tests {
     state
       .auto_update_downloads
       .insert("firefox-1.1.0".to_string());
-    let json = serde_json::to_string_pretty(&state).unwrap();
-    std::fs::write(&state_file, json).unwrap();
+    let json = serde_json::to_string_pretty(&state).expect("Failed to serialize state");
+    std::fs::write(&state_file, json).expect("Failed to write state file");
 
     // Check that it's disabled
-    let content = std::fs::read_to_string(&state_file).unwrap();
-    let loaded_state: AutoUpdateState = serde_json::from_str(&content).unwrap();
-    assert!(loaded_state.disabled_browsers.contains("firefox"));
-    assert!(loaded_state.auto_update_downloads.contains("firefox-1.1.0"));
+    let content = std::fs::read_to_string(&state_file).expect("Failed to read state file");
+    let loaded_state: AutoUpdateState =
+      serde_json::from_str(&content).expect("Failed to deserialize state");
+    assert!(
+      loaded_state.disabled_browsers.contains("firefox"),
+      "Firefox should be disabled"
+    );
+    assert!(
+      loaded_state.auto_update_downloads.contains("firefox-1.1.0"),
+      "Firefox download should be tracked"
+    );
 
     // Complete update (should enable)
     let mut state = loaded_state;
     state.disabled_browsers.remove("firefox");
     state.auto_update_downloads.remove("firefox-1.1.0");
-    let json = serde_json::to_string_pretty(&state).unwrap();
-    std::fs::write(&state_file, json).unwrap();
+    let json = serde_json::to_string_pretty(&state).expect("Failed to serialize final state");
+    std::fs::write(&state_file, json).expect("Failed to write final state file");
 
     // Check that it's enabled again
-    let content = std::fs::read_to_string(&state_file).unwrap();
-    let final_state: AutoUpdateState = serde_json::from_str(&content).unwrap();
-    assert!(!final_state.disabled_browsers.contains("firefox"));
-    assert!(!final_state.auto_update_downloads.contains("firefox-1.1.0"));
+    let content = std::fs::read_to_string(&state_file).expect("Failed to read final state file");
+    let final_state: AutoUpdateState =
+      serde_json::from_str(&content).expect("Failed to deserialize final state");
+    assert!(
+      !final_state.disabled_browsers.contains("firefox"),
+      "Firefox should be enabled again"
+    );
+    assert!(
+      !final_state.auto_update_downloads.contains("firefox-1.1.0"),
+      "Firefox download should not be tracked anymore"
+    );
   }
 
   #[test]
@@ -863,7 +883,7 @@ mod tests {
     use tempfile::TempDir;
 
     // Create a temporary directory for testing
-    let temp_dir = TempDir::new().unwrap();
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
 
     // Create a mock settings manager that uses the temp directory
     struct TestSettingsManager {
@@ -897,21 +917,27 @@ mod tests {
     let state_file = test_settings_manager
       .get_settings_dir()
       .join("auto_update_state.json");
-    std::fs::create_dir_all(test_settings_manager.get_settings_dir()).unwrap();
-    let json = serde_json::to_string_pretty(&state).unwrap();
-    std::fs::write(&state_file, json).unwrap();
+    std::fs::create_dir_all(test_settings_manager.get_settings_dir())
+      .expect("Failed to create settings directory");
+    let json = serde_json::to_string_pretty(&state).expect("Failed to serialize initial state");
+    std::fs::write(&state_file, json).expect("Failed to write initial state file");
 
     // Dismiss notification (remove from pending updates)
     state
       .pending_updates
       .retain(|n| n.id != "test_notification");
-    let json = serde_json::to_string_pretty(&state).unwrap();
-    std::fs::write(&state_file, json).unwrap();
+    let json = serde_json::to_string_pretty(&state).expect("Failed to serialize updated state");
+    std::fs::write(&state_file, json).expect("Failed to write updated state file");
 
     // Check that it's removed
-    let content = std::fs::read_to_string(&state_file).unwrap();
-    let loaded_state: AutoUpdateState = serde_json::from_str(&content).unwrap();
-    assert_eq!(loaded_state.pending_updates.len(), 0);
+    let content = std::fs::read_to_string(&state_file).expect("Failed to read updated state file");
+    let loaded_state: AutoUpdateState =
+      serde_json::from_str(&content).expect("Failed to deserialize updated state");
+    assert_eq!(
+      loaded_state.pending_updates.len(),
+      0,
+      "Pending updates should be empty after dismissal"
+    );
   }
 }
 
diff --git a/src-tauri/src/browser.rs b/src-tauri/src/browser.rs
index fc5a626..58dd3b0 100644
--- a/src-tauri/src/browser.rs
+++ b/src-tauri/src/browser.rs
@@ -889,38 +889,55 @@ mod tests {
     assert_eq!(BrowserType::TorBrowser.as_str(), "tor-browser");
     assert_eq!(BrowserType::Camoufox.as_str(), "camoufox");
 
-    // Test from_str
+    // Test from_str - use expect with descriptive messages instead of unwrap
     assert_eq!(
-      BrowserType::from_str("mullvad-browser").unwrap(),
+      BrowserType::from_str("mullvad-browser").expect("mullvad-browser should be valid"),
       BrowserType::MullvadBrowser
     );
     assert_eq!(
-      BrowserType::from_str("firefox").unwrap(),
+      BrowserType::from_str("firefox").expect("firefox should be valid"),
       BrowserType::Firefox
     );
     assert_eq!(
-      BrowserType::from_str("firefox-developer").unwrap(),
+      BrowserType::from_str("firefox-developer").expect("firefox-developer should be valid"),
       BrowserType::FirefoxDeveloper
     );
     assert_eq!(
-      BrowserType::from_str("chromium").unwrap(),
+      BrowserType::from_str("chromium").expect("chromium should be valid"),
       BrowserType::Chromium
     );
-    assert_eq!(BrowserType::from_str("brave").unwrap(), BrowserType::Brave);
-    assert_eq!(BrowserType::from_str("zen").unwrap(), BrowserType::Zen);
     assert_eq!(
-      BrowserType::from_str("tor-browser").unwrap(),
+      BrowserType::from_str("brave").expect("brave should be valid"),
+      BrowserType::Brave
+    );
+    assert_eq!(
+      BrowserType::from_str("zen").expect("zen should be valid"),
+      BrowserType::Zen
+    );
+    assert_eq!(
+      BrowserType::from_str("tor-browser").expect("tor-browser should be valid"),
       BrowserType::TorBrowser
     );
     assert_eq!(
-      BrowserType::from_str("camoufox").unwrap(),
+      BrowserType::from_str("camoufox").expect("camoufox should be valid"),
       BrowserType::Camoufox
     );
 
-    // Test invalid browser type
-    assert!(BrowserType::from_str("invalid").is_err());
-    assert!(BrowserType::from_str("").is_err());
-    assert!(BrowserType::from_str("Firefox").is_err()); // Case sensitive
+    // Test invalid browser type - these should properly fail
+    let invalid_result = BrowserType::from_str("invalid");
+    assert!(
+      invalid_result.is_err(),
+      "Invalid browser type should return error"
+    );
+
+    let empty_result = BrowserType::from_str("");
+    assert!(empty_result.is_err(), "Empty string should return error");
+
+    let case_sensitive_result = BrowserType::from_str("Firefox");
+    assert!(
+      case_sensitive_result.is_err(),
+      "Case sensitive check should fail"
+    );
   }
 
   #[test]
@@ -929,9 +946,12 @@ mod tests {
     let browser = FirefoxBrowser::new(BrowserType::Firefox);
     let args = browser
       .create_launch_args("/path/to/profile", None, None)
-      .unwrap();
+      .expect("Failed to create launch args for Firefox");
     assert_eq!(args, vec!["-profile", "/path/to/profile"]);
-    assert!(!args.contains(&"-no-remote".to_string()));
+    assert!(
+      !args.contains(&"-no-remote".to_string()),
+      "Firefox should not use -no-remote"
+    );
 
     let args = browser
       .create_launch_args(
@@ -939,7 +959,7 @@ mod tests {
         None,
         Some("https://example.com".to_string()),
       )
-      .unwrap();
+      .expect("Failed to create launch args for Firefox with URL");
     assert_eq!(
       args,
       vec!["-profile", "/path/to/profile", "https://example.com"]
@@ -949,23 +969,26 @@ mod tests {
     let browser = FirefoxBrowser::new(BrowserType::MullvadBrowser);
     let args = browser
       .create_launch_args("/path/to/profile", None, None)
-      .unwrap();
+      .expect("Failed to create launch args for Mullvad Browser");
     assert_eq!(args, vec!["-profile", "/path/to/profile", "-no-remote"]);
 
     // Test Tor Browser (should use -no-remote)
     let browser = FirefoxBrowser::new(BrowserType::TorBrowser);
     let args = browser
       .create_launch_args("/path/to/profile", None, None)
-      .unwrap();
+      .expect("Failed to create launch args for Tor Browser");
     assert_eq!(args, vec!["-profile", "/path/to/profile", "-no-remote"]);
 
     // Test Zen Browser (should not use -no-remote)
     let browser = FirefoxBrowser::new(BrowserType::Zen);
     let args = browser
       .create_launch_args("/path/to/profile", None, None)
-      .unwrap();
+      .expect("Failed to create launch args for Zen Browser");
     assert_eq!(args, vec!["-profile", "/path/to/profile"]);
-    assert!(!args.contains(&"-no-remote".to_string()));
+    assert!(
+      !args.contains(&"-no-remote".to_string()),
+      "Zen Browser should not use -no-remote"
+    );
   }
 
   #[test]
@@ -973,15 +996,27 @@ mod tests {
     let browser = ChromiumBrowser::new(BrowserType::Chromium);
     let args = browser
       .create_launch_args("/path/to/profile", None, None)
-      .unwrap();
+      .expect("Failed to create launch args for Chromium");
 
     // Test that basic required arguments are present
-    assert!(args.contains(&"--user-data-dir=/path/to/profile".to_string()));
-    assert!(args.contains(&"--no-default-browser-check".to_string()));
+    assert!(
+      args.contains(&"--user-data-dir=/path/to/profile".to_string()),
+      "Chromium args should contain user-data-dir"
+    );
+    assert!(
+      args.contains(&"--no-default-browser-check".to_string()),
+      "Chromium args should contain no-default-browser-check"
+    );
 
     // Test that automatic update disabling arguments are present
-    assert!(args.contains(&"--disable-background-mode".to_string()));
-    assert!(args.contains(&"--disable-component-update".to_string()));
+    assert!(
+      args.contains(&"--disable-background-mode".to_string()),
+      "Chromium args should contain disable-background-mode"
+    );
+    assert!(
+      args.contains(&"--disable-component-update".to_string()),
+      "Chromium args should contain disable-component-update"
+    );
 
     let args_with_url = browser
       .create_launch_args(
@@ -989,11 +1024,17 @@ mod tests {
         None,
         Some("https://example.com".to_string()),
       )
-      .unwrap();
-    assert!(args_with_url.contains(&"https://example.com".to_string()));
+      .expect("Failed to create launch args for Chromium with URL");
+    assert!(
+      args_with_url.contains(&"https://example.com".to_string()),
+      "Chromium args should contain the URL"
+    );
 
     // Verify URL is at the end
-    assert_eq!(args_with_url.last().unwrap(), "https://example.com");
+    assert_eq!(
+      args_with_url.last().expect("Args should not be empty"),
+      "https://example.com"
+    );
   }
 
   #[test]
@@ -1026,40 +1067,44 @@ mod tests {
 
   #[test]
   fn test_version_downloaded_check() {
-    let temp_dir = TempDir::new().unwrap();
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
     let binaries_dir = temp_dir.path();
 
     // Create a mock Firefox browser installation with new path structure: binaries/<browser>/<version>/
     let browser_dir = binaries_dir.join("firefox").join("139.0");
-    fs::create_dir_all(&browser_dir).unwrap();
+    fs::create_dir_all(&browser_dir).expect("Failed to create browser directory");
 
     #[cfg(target_os = "macos")]
     {
       // Create a mock .app directory for macOS
       let app_dir = browser_dir.join("Firefox.app");
-      fs::create_dir_all(&app_dir).unwrap();
+      fs::create_dir_all(&app_dir).expect("Failed to create Firefox.app directory");
     }
 
     #[cfg(target_os = "linux")]
     {
       // Create a mock firefox subdirectory and executable for Linux
       let firefox_subdir = browser_dir.join("firefox");
-      fs::create_dir_all(&firefox_subdir).unwrap();
+      fs::create_dir_all(&firefox_subdir).expect("Failed to create firefox subdirectory");
       let executable_path = firefox_subdir.join("firefox");
-      fs::write(&executable_path, "mock executable").unwrap();
+      fs::write(&executable_path, "mock executable").expect("Failed to write mock executable");
 
       // Set executable permissions on Linux
       use std::os::unix::fs::PermissionsExt;
-      let mut permissions = executable_path.metadata().unwrap().permissions();
+      let mut permissions = executable_path
+        .metadata()
+        .expect("Failed to get file metadata")
+        .permissions();
       permissions.set_mode(0o755);
-      fs::set_permissions(&executable_path, permissions).unwrap();
+      fs::set_permissions(&executable_path, permissions)
+        .expect("Failed to set executable permissions");
     }
 
     #[cfg(target_os = "windows")]
     {
       // Create a mock firefox.exe for Windows
       let executable_path = browser_dir.join("firefox.exe");
-      fs::write(&executable_path, "mock executable").unwrap();
+      fs::write(&executable_path, "mock executable").expect("Failed to write mock executable");
     }
 
     let browser = FirefoxBrowser::new(BrowserType::Firefox);
@@ -1068,60 +1113,76 @@ mod tests {
 
     // Test with Chromium browser with new path structure
     let chromium_dir = binaries_dir.join("chromium").join("1465660");
-    fs::create_dir_all(&chromium_dir).unwrap();
+    fs::create_dir_all(&chromium_dir).expect("Failed to create chromium directory");
 
     #[cfg(target_os = "macos")]
     {
       let chromium_app_dir = chromium_dir.join("Chromium.app");
-      fs::create_dir_all(chromium_app_dir.join("Contents").join("MacOS")).unwrap();
+      fs::create_dir_all(chromium_app_dir.join("Contents").join("MacOS"))
+        .expect("Failed to create Chromium.app structure");
 
       // Create a mock executable
       let executable_path = chromium_app_dir
         .join("Contents")
         .join("MacOS")
         .join("Chromium");
-      fs::write(&executable_path, "mock executable").unwrap();
+      fs::write(&executable_path, "mock executable")
+        .expect("Failed to write mock Chromium executable");
     }
 
     #[cfg(target_os = "linux")]
     {
       // Create a mock chromium executable for Linux
       let executable_path = chromium_dir.join("chromium");
-      fs::write(&executable_path, "mock executable").unwrap();
+      fs::write(&executable_path, "mock executable")
+        .expect("Failed to write mock chromium executable");
 
       // Set executable permissions on Linux
       use std::os::unix::fs::PermissionsExt;
-      let mut permissions = executable_path.metadata().unwrap().permissions();
+      let mut permissions = executable_path
+        .metadata()
+        .expect("Failed to get chromium metadata")
+        .permissions();
       permissions.set_mode(0o755);
-      fs::set_permissions(&executable_path, permissions).unwrap();
+      fs::set_permissions(&executable_path, permissions)
+        .expect("Failed to set chromium permissions");
     }
 
     #[cfg(target_os = "windows")]
     {
       // Create a mock chromium.exe for Windows
       let executable_path = chromium_dir.join("chromium.exe");
-      fs::write(&executable_path, "mock executable").unwrap();
+      fs::write(&executable_path, "mock executable").expect("Failed to write mock chromium.exe");
     }
 
     let chromium_browser = ChromiumBrowser::new(BrowserType::Chromium);
-    assert!(chromium_browser.is_version_downloaded("1465660", binaries_dir));
-    assert!(!chromium_browser.is_version_downloaded("1465661", binaries_dir));
+    assert!(
+      chromium_browser.is_version_downloaded("1465660", binaries_dir),
+      "Chromium version should be detected as downloaded"
+    );
+    assert!(
+      !chromium_browser.is_version_downloaded("1465661", binaries_dir),
+      "Non-existent Chromium version should not be detected as downloaded"
+    );
   }
 
   #[test]
   fn test_version_downloaded_no_app_directory() {
-    let temp_dir = TempDir::new().unwrap();
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
     let binaries_dir = temp_dir.path();
 
     // Create browser directory but no proper executable structure
     let browser_dir = binaries_dir.join("firefox").join("139.0");
-    fs::create_dir_all(&browser_dir).unwrap();
+    fs::create_dir_all(&browser_dir).expect("Failed to create browser directory");
 
     // Create some other files but no proper executable structure
-    fs::write(browser_dir.join("readme.txt"), "Some content").unwrap();
+    fs::write(browser_dir.join("readme.txt"), "Some content").expect("Failed to write readme file");
 
     let browser = FirefoxBrowser::new(BrowserType::Firefox);
-    assert!(!browser.is_version_downloaded("139.0", binaries_dir));
+    assert!(
+      !browser.is_version_downloaded("139.0", binaries_dir),
+      "Firefox version should not be detected without proper executable structure"
+    );
   }
 
   #[test]
@@ -1146,16 +1207,20 @@ mod tests {
     };
 
     // Test that it can be serialized (implements Serialize)
-    let json = serde_json::to_string(&proxy).unwrap();
-    assert!(json.contains("127.0.0.1"));
-    assert!(json.contains("8080"));
-    assert!(json.contains("http"));
+    let json = serde_json::to_string(&proxy).expect("Failed to serialize proxy settings");
+    assert!(json.contains("127.0.0.1"), "JSON should contain host IP");
+    assert!(json.contains("8080"), "JSON should contain port number");
+    assert!(json.contains("http"), "JSON should contain proxy type");
 
     // Test that it can be deserialized (implements Deserialize)
-    let deserialized: ProxySettings = serde_json::from_str(&json).unwrap();
-    assert_eq!(deserialized.proxy_type, proxy.proxy_type);
-    assert_eq!(deserialized.host, proxy.host);
-    assert_eq!(deserialized.port, proxy.port);
+    let deserialized: ProxySettings =
+      serde_json::from_str(&json).expect("Failed to deserialize proxy settings");
+    assert_eq!(
+      deserialized.proxy_type, proxy.proxy_type,
+      "Proxy type should match"
+    );
+    assert_eq!(deserialized.host, proxy.host, "Host should match");
+    assert_eq!(deserialized.port, proxy.port, "Port should match");
   }
 }
 
diff --git a/src-tauri/src/downloaded_browsers.rs b/src-tauri/src/downloaded_browsers.rs
index 6885d31..1018ffa 100644
--- a/src-tauri/src/downloaded_browsers.rs
+++ b/src-tauri/src/downloaded_browsers.rs
@@ -496,15 +496,21 @@ mod tests {
     registry.mark_download_started("firefox", "139.0", PathBuf::from("/test/path"));
 
     // Should be considered downloaded immediately
-    assert!(registry.is_browser_downloaded("firefox", "139.0"));
+    assert!(
+      registry.is_browser_downloaded("firefox", "139.0"),
+      "Browser should be considered downloaded after marking as started"
+    );
 
     // Mark as completed
     registry
       .mark_download_completed("firefox", "139.0")
-      .unwrap();
+      .expect("Failed to mark download as completed");
 
     // Should still be considered downloaded
-    assert!(registry.is_browser_downloaded("firefox", "139.0"));
+    assert!(
+      registry.is_browser_downloaded("firefox", "139.0"),
+      "Browser should still be considered downloaded after completion"
+    );
   }
 
   #[test]
@@ -517,11 +523,20 @@ mod tests {
     };
 
     registry.add_browser(info);
-    assert!(registry.is_browser_downloaded("firefox", "139.0"));
+    assert!(
+      registry.is_browser_downloaded("firefox", "139.0"),
+      "Browser should be downloaded after adding"
+    );
 
     let removed = registry.remove_browser("firefox", "139.0");
-    assert!(removed.is_some());
-    assert!(!registry.is_browser_downloaded("firefox", "139.0"));
+    assert!(
+      removed.is_some(),
+      "Remove operation should return the removed browser info"
+    );
+    assert!(
+      !registry.is_browser_downloaded("firefox", "139.0"),
+      "Browser should not be downloaded after removal"
+    );
   }
 
   #[test]
@@ -532,6 +547,9 @@ mod tests {
     registry.mark_download_started("zen", "twilight", PathBuf::from("/test/zen-twilight"));
 
     // Check that it's registered
-    assert!(registry.is_browser_downloaded("zen", "twilight"));
+    assert!(
+      registry.is_browser_downloaded("zen", "twilight"),
+      "Zen twilight version should be registered as downloaded"
+    );
   }
 }
diff --git a/src-tauri/src/extraction.rs b/src-tauri/src/extraction.rs
index 6ae2b66..e7c1953 100644
--- a/src-tauri/src/extraction.rs
+++ b/src-tauri/src/extraction.rs
@@ -1444,93 +1444,211 @@ mod tests {
   #[tokio::test]
   async fn test_extract_zip_with_test_archive() {
     let extractor = Extractor::instance();
-    let temp_dir = TempDir::new().unwrap();
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
     let dest_dir = temp_dir.path().join("extracted");
 
-    // Use the test ZIP archive
-    let zip_path = std::path::Path::new("test-assets/test.zip");
-    if !zip_path.exists() {
-      // Skip test if test archive doesn't exist
-      return;
+    // Create a test ZIP archive in memory
+    let zip_path = temp_dir.path().join("test.zip");
+    {
+      let file = std::fs::File::create(&zip_path).expect("Failed to create test zip file");
+      let mut zip = zip::ZipWriter::new(file);
+
+      let options =
+        zip::write::FileOptions::<()>::default().compression_method(zip::CompressionMethod::Stored);
+
+      zip
+        .start_file("test.txt", options)
+        .expect("Failed to start zip file");
+      zip
+        .write_all(b"Hello, World!")
+        .expect("Failed to write to zip");
+      zip.finish().expect("Failed to finish zip");
     }
 
-    let _result = extractor.extract_zip(zip_path, &dest_dir).await;
+    let result = extractor.extract_zip(&zip_path, &dest_dir).await;
 
     // The result might fail because we're looking for executables, but the extraction should work
-    // Let's just check if the file was extracted
+    // Let's check if the file was extracted regardless of the result
     let extracted_file = dest_dir.join("test.txt");
-    if extracted_file.exists() {
-      let content = std::fs::read_to_string(&extracted_file).unwrap();
-      assert_eq!(content.trim(), "Hello, World!");
+    assert!(extracted_file.exists(), "Extracted file should exist");
+
+    let content = std::fs::read_to_string(&extracted_file).expect("Failed to read extracted file");
+    assert_eq!(
+      content.trim(),
+      "Hello, World!",
+      "Extracted content should match"
+    );
+
+    // If the result is an error, it should be because no executable was found, not extraction failure
+    if let Err(e) = result {
+      let error_msg = e.to_string();
+      assert!(
+        error_msg.contains("No executable found") || error_msg.contains("executable"),
+        "Error should be about missing executable, not extraction failure: {error_msg}"
+      );
     }
   }
 
   #[tokio::test]
   async fn test_extract_tar_gz_with_test_archive() {
     let extractor = Extractor::instance();
-    let temp_dir = TempDir::new().unwrap();
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
     let dest_dir = temp_dir.path().join("extracted");
 
-    // Use the test tar.gz archive
-    let tar_gz_path = std::path::Path::new("test-assets/test.tar.gz");
-    if !tar_gz_path.exists() {
-      // Skip test if test archive doesn't exist
-      return;
+    // Create a test tar.gz archive in memory
+    let tar_gz_path = temp_dir.path().join("test.tar.gz");
+    {
+      let tar_gz_file =
+        std::fs::File::create(&tar_gz_path).expect("Failed to create test tar.gz file");
+      let enc = flate2::write::GzEncoder::new(tar_gz_file, flate2::Compression::default());
+      let mut tar = tar::Builder::new(enc);
+
+      let mut header = tar::Header::new_gnu();
+      header.set_path("test.txt").expect("Failed to set tar path");
+      header.set_size(13); // "Hello, World!" length
+      header.set_cksum();
+
+      tar
+        .append(&header, "Hello, World!".as_bytes())
+        .expect("Failed to append to tar");
+      tar.finish().expect("Failed to finish tar");
     }
 
-    let _result = extractor.extract_tar_gz(tar_gz_path, &dest_dir).await;
+    let result = extractor.extract_tar_gz(&tar_gz_path, &dest_dir).await;
 
     // Check if the file was extracted
     let extracted_file = dest_dir.join("test.txt");
-    if extracted_file.exists() {
-      let content = std::fs::read_to_string(&extracted_file).unwrap();
-      assert_eq!(content.trim(), "Hello, World!");
+    assert!(extracted_file.exists(), "Extracted file should exist");
+
+    let content = std::fs::read_to_string(&extracted_file).expect("Failed to read extracted file");
+    assert_eq!(
+      content.trim(),
+      "Hello, World!",
+      "Extracted content should match"
+    );
+
+    // If the result is an error, it should be because no executable was found, not extraction failure
+    if let Err(e) = result {
+      let error_msg = e.to_string();
+      assert!(
+        error_msg.contains("No executable found")
+          || error_msg.contains("executable")
+          || error_msg.contains("No .app found")
+          || error_msg.contains("app not found"),
+        "Error should be about missing executable/app, not extraction failure: {error_msg}"
+      );
     }
   }
 
   #[tokio::test]
   async fn test_extract_tar_bz2_with_test_archive() {
     let extractor = Extractor::instance();
-    let temp_dir = TempDir::new().unwrap();
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
     let dest_dir = temp_dir.path().join("extracted");
 
-    // Use the test tar.bz2 archive
-    let tar_bz2_path = std::path::Path::new("test-assets/test.tar.bz2");
-    if !tar_bz2_path.exists() {
-      // Skip test if test archive doesn't exist
-      return;
+    // Create a test tar.bz2 archive in memory
+    let tar_bz2_path = temp_dir.path().join("test.tar.bz2");
+    {
+      let tar_bz2_file =
+        std::fs::File::create(&tar_bz2_path).expect("Failed to create test tar.bz2 file");
+      let enc = bzip2::write::BzEncoder::new(tar_bz2_file, bzip2::Compression::default());
+      let mut tar = tar::Builder::new(enc);
+
+      let mut header = tar::Header::new_gnu();
+      header.set_path("test.txt").expect("Failed to set tar path");
+      header.set_size(13); // "Hello, World!" length
+      header.set_cksum();
+
+      tar
+        .append(&header, "Hello, World!".as_bytes())
+        .expect("Failed to append to tar");
+      tar.finish().expect("Failed to finish tar");
     }
 
-    let _result = extractor.extract_tar_bz2(tar_bz2_path, &dest_dir).await;
+    let result = extractor.extract_tar_bz2(&tar_bz2_path, &dest_dir).await;
 
     // Check if the file was extracted
     let extracted_file = dest_dir.join("test.txt");
-    if extracted_file.exists() {
-      let content = std::fs::read_to_string(&extracted_file).unwrap();
-      assert_eq!(content.trim(), "Hello, World!");
+    assert!(extracted_file.exists(), "Extracted file should exist");
+
+    let content = std::fs::read_to_string(&extracted_file).expect("Failed to read extracted file");
+    assert_eq!(
+      content.trim(),
+      "Hello, World!",
+      "Extracted content should match"
+    );
+
+    // If the result is an error, it should be because no executable was found, not extraction failure
+    if let Err(e) = result {
+      let error_msg = e.to_string();
+      assert!(
+        error_msg.contains("No executable found")
+          || error_msg.contains("executable")
+          || error_msg.contains("No .app found")
+          || error_msg.contains("app not found"),
+        "Error should be about missing executable/app, not extraction failure: {error_msg}"
+      );
     }
   }
 
   #[tokio::test]
   async fn test_extract_tar_xz_with_test_archive() {
     let extractor = Extractor::instance();
-    let temp_dir = TempDir::new().unwrap();
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
     let dest_dir = temp_dir.path().join("extracted");
 
-    // Use the test tar.xz archive
-    let tar_xz_path = std::path::Path::new("test-assets/test.tar.xz");
-    if !tar_xz_path.exists() {
-      // Skip test if test archive doesn't exist
-      return;
+    // Create a test tar.xz archive in memory
+    let tar_xz_path = temp_dir.path().join("test.tar.xz");
+    {
+      // First create a tar archive in memory
+      let mut tar_data = Vec::new();
+      {
+        let mut tar = tar::Builder::new(&mut tar_data);
+
+        let mut header = tar::Header::new_gnu();
+        header.set_path("test.txt").expect("Failed to set tar path");
+        header.set_size(13); // "Hello, World!" length
+        header.set_cksum();
+
+        tar
+          .append(&header, "Hello, World!".as_bytes())
+          .expect("Failed to append to tar");
+        tar.finish().expect("Failed to finish tar");
+      }
+
+      // Then compress with xz
+      let tar_xz_file =
+        std::fs::File::create(&tar_xz_path).expect("Failed to create test tar.xz file");
+      let mut compressed_data = Vec::new();
+      lzma_rs::xz_compress(&mut std::io::Cursor::new(tar_data), &mut compressed_data)
+        .expect("Failed to compress with xz");
+      std::io::Write::write_all(&mut std::io::BufWriter::new(tar_xz_file), &compressed_data)
+        .expect("Failed to write compressed data");
     }
 
-    let _result = extractor.extract_tar_xz(tar_xz_path, &dest_dir).await;
+    let result = extractor.extract_tar_xz(&tar_xz_path, &dest_dir).await;
 
     // Check if the file was extracted
     let extracted_file = dest_dir.join("test.txt");
-    if extracted_file.exists() {
-      let content = std::fs::read_to_string(&extracted_file).unwrap();
-      assert_eq!(content.trim(), "Hello, World!");
+    assert!(extracted_file.exists(), "Extracted file should exist");
+
+    let content = std::fs::read_to_string(&extracted_file).expect("Failed to read extracted file");
+    assert_eq!(
+      content.trim(),
+      "Hello, World!",
+      "Extracted content should match"
+    );
+
+    // If the result is an error, it should be because no executable was found, not extraction failure
+    if let Err(e) = result {
+      let error_msg = e.to_string();
+      assert!(
+        error_msg.contains("No executable found")
+          || error_msg.contains("executable")
+          || error_msg.contains("No .app found")
+          || error_msg.contains("app not found"),
+        "Error should be about missing executable/app, not extraction failure: {error_msg}"
+      );
     }
   }
 
@@ -1578,27 +1696,69 @@ mod tests {
     assert!(found_app.exists());
   }
 
-  #[cfg(target_os = "linux")]
   #[test]
   fn test_is_executable() {
+    #[allow(unused_variables)]
     let extractor = Extractor::instance();
-    let temp_dir = TempDir::new().unwrap();
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
 
     // Create a regular file
     let regular_file = temp_dir.path().join("regular.txt");
-    File::create(&regular_file).unwrap();
+    File::create(&regular_file).expect("Failed to create test file");
 
-    // Should not be executable initially
-    assert!(!extractor.is_executable(&regular_file));
+    #[cfg(target_os = "linux")]
+    {
+      // Should not be executable initially
+      assert!(
+        !extractor.is_executable(&regular_file),
+        "File should not be executable initially"
+      );
 
-    // Make it executable
-    use std::os::unix::fs::PermissionsExt;
-    let mut permissions = regular_file.metadata().unwrap().permissions();
-    permissions.set_mode(0o755);
-    std::fs::set_permissions(&regular_file, permissions).unwrap();
+      // Make it executable
+      use std::os::unix::fs::PermissionsExt;
+      let mut permissions = regular_file
+        .metadata()
+        .expect("Failed to get file metadata")
+        .permissions();
+      permissions.set_mode(0o755);
+      std::fs::set_permissions(&regular_file, permissions).expect("Failed to set permissions");
 
-    // Should now be executable
-    assert!(extractor.is_executable(&regular_file));
+      // Should now be executable
+      assert!(
+        extractor.is_executable(&regular_file),
+        "File should be executable after setting permissions"
+      );
+    }
+
+    #[cfg(not(target_os = "linux"))]
+    {
+      // On non-Linux systems, the is_executable method is not available
+      // We'll just verify the file exists since executable permissions work differently on Windows/macOS
+      assert!(regular_file.exists(), "Test file should exist");
+
+      // On Unix systems (but not Linux), we can still test basic permission setting
+      #[cfg(unix)]
+      {
+        use std::os::unix::fs::PermissionsExt;
+        let mut permissions = regular_file
+          .metadata()
+          .expect("Failed to get file metadata")
+          .permissions();
+        permissions.set_mode(0o755);
+        std::fs::set_permissions(&regular_file, permissions).expect("Failed to set permissions");
+
+        // Verify the permissions were set
+        let new_permissions = regular_file
+          .metadata()
+          .expect("Failed to get updated metadata")
+          .permissions();
+        assert_eq!(
+          new_permissions.mode() & 0o777,
+          0o755,
+          "Permissions should be set to 755"
+        );
+      }
+    }
   }
 }
 
diff --git a/src-tauri/src/geoip_downloader.rs b/src-tauri/src/geoip_downloader.rs
index de0aeb2..ac4b13d 100644
--- a/src-tauri/src/geoip_downloader.rs
+++ b/src-tauri/src/geoip_downloader.rs
@@ -293,12 +293,26 @@ mod tests {
 
   #[test]
   fn test_is_geoip_database_available() {
-    // This test will return false unless the database actually exists
-    // In a real environment, this would check the actual file system
+    // Test that the function works correctly regardless of file system state
     let is_available = GeoIPDownloader::is_geoip_database_available();
-    // We can't assert a specific value since it depends on the system state
-    // But we can verify the function doesn't panic
-    println!("GeoIP database available: {is_available}");
+
+    // The function should return a boolean value (either true or false)
+    // The function should return a boolean value - we just verify it doesn't panic
+    // and returns the expected result based on file existence
+
+    // Verify the function logic by checking if the path resolution works
+    let mmdb_path_result = GeoIPDownloader::get_mmdb_file_path();
+    assert!(
+      mmdb_path_result.is_ok(),
+      "Should be able to get MMDB file path"
+    );
+
+    let mmdb_path = mmdb_path_result.unwrap();
+    let expected_available = mmdb_path.exists();
+    assert_eq!(
+      is_available, expected_available,
+      "Function result should match actual file existence"
+    );
   }
 }
 
diff --git a/src-tauri/src/group_manager.rs b/src-tauri/src/group_manager.rs
index 930f3d9..69c7f90 100644
--- a/src-tauri/src/group_manager.rs
+++ b/src-tauri/src/group_manager.rs
@@ -185,6 +185,258 @@ lazy_static::lazy_static! {
   pub static ref GROUP_MANAGER: Mutex<GroupManager> = Mutex::new(GroupManager::new());
 }
 
+#[cfg(test)]
+mod tests {
+  use super::*;
+  use std::env;
+  use tempfile::TempDir;
+
+  fn create_test_group_manager() -> (GroupManager, TempDir) {
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
+
+    // Set up a temporary home directory for testing
+    env::set_var("HOME", temp_dir.path());
+
+    let manager = GroupManager::new();
+    (manager, temp_dir)
+  }
+
+  #[test]
+  fn test_group_manager_creation() {
+    let (_manager, _temp_dir) = create_test_group_manager();
+    // Test passes if no panic occurs
+  }
+
+  #[test]
+  fn test_create_and_get_groups() {
+    let (manager, _temp_dir) = create_test_group_manager();
+
+    // Initially should have no groups
+    let groups = manager
+      .get_all_groups()
+      .expect("Should be able to get groups");
+    assert!(groups.is_empty(), "Should start with no groups");
+
+    // Create a group
+    let group_name = "Test Group".to_string();
+    let created_group = manager
+      .create_group(group_name.clone())
+      .expect("Should create group successfully");
+
+    assert_eq!(
+      created_group.name, group_name,
+      "Created group should have correct name"
+    );
+    assert!(
+      !created_group.id.is_empty(),
+      "Created group should have an ID"
+    );
+
+    // Verify group was saved
+    let groups = manager
+      .get_all_groups()
+      .expect("Should be able to get groups");
+    assert_eq!(groups.len(), 1, "Should have one group");
+    assert_eq!(
+      groups[0].name, group_name,
+      "Retrieved group should have correct name"
+    );
+    assert_eq!(
+      groups[0].id, created_group.id,
+      "Retrieved group should have correct ID"
+    );
+  }
+
+  #[test]
+  fn test_create_duplicate_group_fails() {
+    let (manager, _temp_dir) = create_test_group_manager();
+
+    let group_name = "Duplicate Group".to_string();
+
+    // Create first group
+    let _first_group = manager
+      .create_group(group_name.clone())
+      .expect("Should create first group");
+
+    // Try to create duplicate group
+    let result = manager.create_group(group_name.clone());
+    assert!(result.is_err(), "Should fail to create duplicate group");
+
+    let error_msg = result.unwrap_err().to_string();
+    assert!(
+      error_msg.contains("already exists"),
+      "Error should mention group already exists"
+    );
+  }
+
+  #[test]
+  fn test_update_group() {
+    let (manager, _temp_dir) = create_test_group_manager();
+
+    // Create a group
+    let original_name = "Original Name".to_string();
+    let created_group = manager
+      .create_group(original_name)
+      .expect("Should create group");
+
+    // Update the group
+    let new_name = "Updated Name".to_string();
+    let updated_group = manager
+      .update_group(created_group.id.clone(), new_name.clone())
+      .expect("Should update group successfully");
+
+    assert_eq!(
+      updated_group.name, new_name,
+      "Updated group should have new name"
+    );
+    assert_eq!(
+      updated_group.id, created_group.id,
+      "Updated group should keep same ID"
+    );
+
+    // Verify update was persisted
+    let groups = manager.get_all_groups().expect("Should get groups");
+    assert_eq!(groups.len(), 1, "Should still have one group");
+    assert_eq!(
+      groups[0].name, new_name,
+      "Persisted group should have updated name"
+    );
+  }
+
+  #[test]
+  fn test_update_nonexistent_group_fails() {
+    let (manager, _temp_dir) = create_test_group_manager();
+
+    let result = manager.update_group("nonexistent-id".to_string(), "New Name".to_string());
+    assert!(result.is_err(), "Should fail to update nonexistent group");
+
+    let error_msg = result.unwrap_err().to_string();
+    assert!(
+      error_msg.contains("not found"),
+      "Error should mention group not found"
+    );
+  }
+
+  #[test]
+  fn test_delete_group() {
+    let (manager, _temp_dir) = create_test_group_manager();
+
+    // Create a group
+    let group_name = "To Delete".to_string();
+    let created_group = manager
+      .create_group(group_name)
+      .expect("Should create group");
+
+    // Verify group exists
+    let groups = manager.get_all_groups().expect("Should get groups");
+    assert_eq!(groups.len(), 1, "Should have one group");
+
+    // Delete the group
+    manager
+      .delete_group(created_group.id)
+      .expect("Should delete group successfully");
+
+    // Verify group was deleted
+    let groups = manager.get_all_groups().expect("Should get groups");
+    assert!(groups.is_empty(), "Should have no groups after deletion");
+  }
+
+  #[test]
+  fn test_delete_nonexistent_group_fails() {
+    let (manager, _temp_dir) = create_test_group_manager();
+
+    let result = manager.delete_group("nonexistent-id".to_string());
+    assert!(result.is_err(), "Should fail to delete nonexistent group");
+
+    let error_msg = result.unwrap_err().to_string();
+    assert!(
+      error_msg.contains("not found"),
+      "Error should mention group not found"
+    );
+  }
+
+  #[test]
+  fn test_get_groups_with_profile_counts() {
+    let (manager, _temp_dir) = create_test_group_manager();
+
+    // Create test groups
+    let group1 = manager
+      .create_group("Group 1".to_string())
+      .expect("Should create group 1");
+    let _group2 = manager
+      .create_group("Group 2".to_string())
+      .expect("Should create group 2");
+
+    // Create mock profiles
+    let profiles = vec![
+      crate::profile::BrowserProfile {
+        id: uuid::Uuid::new_v4(),
+        name: "Profile 1".to_string(),
+        browser: "firefox".to_string(),
+        version: "1.0".to_string(),
+        proxy_id: None,
+        process_id: None,
+        last_launch: None,
+        release_type: "stable".to_string(),
+        camoufox_config: None,
+        group_id: Some(group1.id.clone()),
+      },
+      crate::profile::BrowserProfile {
+        id: uuid::Uuid::new_v4(),
+        name: "Profile 2".to_string(),
+        browser: "firefox".to_string(),
+        version: "1.0".to_string(),
+        proxy_id: None,
+        process_id: None,
+        last_launch: None,
+        release_type: "stable".to_string(),
+        camoufox_config: None,
+        group_id: Some(group1.id.clone()),
+      },
+      crate::profile::BrowserProfile {
+        id: uuid::Uuid::new_v4(),
+        name: "Profile 3".to_string(),
+        browser: "firefox".to_string(),
+        version: "1.0".to_string(),
+        proxy_id: None,
+        process_id: None,
+        last_launch: None,
+        release_type: "stable".to_string(),
+        camoufox_config: None,
+        group_id: None, // Default group
+      },
+    ];
+
+    let groups_with_counts = manager
+      .get_groups_with_profile_counts(&profiles)
+      .expect("Should get groups with counts");
+
+    // Should have default group + group1 (_group2 has no profiles so shouldn't appear)
+    assert_eq!(
+      groups_with_counts.len(),
+      2,
+      "Should have 2 groups with profiles"
+    );
+
+    // Check default group
+    let default_group = groups_with_counts
+      .iter()
+      .find(|g| g.id == "default")
+      .expect("Should have default group");
+    assert_eq!(
+      default_group.count, 1,
+      "Default group should have 1 profile"
+    );
+
+    // Check group1
+    let group1_with_count = groups_with_counts
+      .iter()
+      .find(|g| g.id == group1.id)
+      .expect("Should have group1");
+    assert_eq!(group1_with_count.count, 2, "Group1 should have 2 profiles");
+  }
+}
+
 // Helper function to get groups with counts
 pub fn get_groups_with_counts(profiles: &[crate::profile::BrowserProfile]) -> Vec<GroupWithCount> {
   let group_manager = GROUP_MANAGER.lock().unwrap();
diff --git a/src-tauri/src/profile/manager.rs b/src-tauri/src/profile/manager.rs
index d9a1daf..727f017 100644
--- a/src-tauri/src/profile/manager.rs
+++ b/src-tauri/src/profile/manager.rs
@@ -1030,8 +1030,135 @@ mod tests {
     let (manager, _temp_dir) = create_test_profile_manager();
     let profiles_dir = manager.get_profiles_dir();
 
-    assert!(profiles_dir.to_string_lossy().contains("DonutBrowser"));
-    assert!(profiles_dir.to_string_lossy().contains("profiles"));
+    assert!(
+      profiles_dir.to_string_lossy().contains("DonutBrowser"),
+      "Profiles dir should contain DonutBrowser"
+    );
+    assert!(
+      profiles_dir.to_string_lossy().contains("profiles"),
+      "Profiles dir should contain profiles"
+    );
+  }
+
+  #[test]
+  fn test_list_profiles_empty() {
+    let (manager, _temp_dir) = create_test_profile_manager();
+
+    let result = manager.list_profiles();
+    assert!(
+      result.is_ok(),
+      "Should successfully list profiles even when empty"
+    );
+
+    let profiles = result.unwrap();
+    assert!(
+      profiles.is_empty(),
+      "Should return empty vector when no profiles exist"
+    );
+  }
+
+  #[test]
+  fn test_get_common_firefox_preferences() {
+    let (manager, _temp_dir) = create_test_profile_manager();
+
+    let prefs = manager.get_common_firefox_preferences();
+    assert!(!prefs.is_empty(), "Should return non-empty preferences");
+
+    // Check for some expected preferences
+    let prefs_string = prefs.join("\n");
+    assert!(
+      prefs_string.contains("browser.shell.checkDefaultBrowser"),
+      "Should contain default browser check preference"
+    );
+    assert!(
+      prefs_string.contains("app.update.enabled"),
+      "Should contain update preference"
+    );
+  }
+
+  #[test]
+  fn test_get_binaries_dir() {
+    let (manager, _temp_dir) = create_test_profile_manager();
+
+    let binaries_dir = manager.get_binaries_dir();
+    let path_str = binaries_dir.to_string_lossy();
+
+    assert!(
+      path_str.contains("DonutBrowser"),
+      "Binaries dir should contain DonutBrowser"
+    );
+    assert!(
+      path_str.contains("binaries"),
+      "Binaries dir should contain binaries"
+    );
+  }
+
+  #[test]
+  fn test_disable_proxy_settings_in_profile() {
+    let (manager, temp_dir) = create_test_profile_manager();
+
+    // Create a test profile directory
+    let profile_dir = temp_dir.path().join("test_profile");
+    fs::create_dir_all(&profile_dir).expect("Should create profile directory");
+
+    let result = manager.disable_proxy_settings_in_profile(&profile_dir);
+    assert!(result.is_ok(), "Should successfully disable proxy settings");
+
+    // Check that user.js was created
+    let user_js_path = profile_dir.join("user.js");
+    assert!(user_js_path.exists(), "user.js should be created");
+
+    let content = fs::read_to_string(&user_js_path).expect("Should read user.js");
+    assert!(
+      content.contains("network.proxy.type"),
+      "Should contain proxy type setting"
+    );
+    assert!(
+      content.contains("0"),
+      "Should set proxy type to 0 (no proxy)"
+    );
+  }
+
+  #[test]
+  fn test_apply_proxy_settings_to_profile() {
+    let (manager, temp_dir) = create_test_profile_manager();
+
+    // Create a test profile directory structure
+    let uuid_dir = temp_dir.path().join("test_uuid");
+    let profile_dir = uuid_dir.join("profile");
+    fs::create_dir_all(&profile_dir).expect("Should create profile directory");
+
+    let proxy_settings = ProxySettings {
+      proxy_type: "http".to_string(),
+      host: "proxy.example.com".to_string(),
+      port: 8080,
+      username: Some("user".to_string()),
+      password: Some("pass".to_string()),
+    };
+
+    let result = manager.apply_proxy_settings_to_profile(&profile_dir, &proxy_settings, None);
+    assert!(result.is_ok(), "Should successfully apply proxy settings");
+
+    // Check that user.js was created
+    let user_js_path = profile_dir.join("user.js");
+    assert!(user_js_path.exists(), "user.js should be created");
+
+    let content = fs::read_to_string(&user_js_path).expect("Should read user.js");
+    assert!(
+      content.contains("network.proxy.type"),
+      "Should contain proxy type setting"
+    );
+    assert!(content.contains("2"), "Should set proxy type to 2 (PAC)");
+
+    // Check that PAC file was created
+    let pac_path = uuid_dir.join("proxy.pac");
+    assert!(pac_path.exists(), "proxy.pac should be created");
+
+    let pac_content = fs::read_to_string(&pac_path).expect("Should read proxy.pac");
+    assert!(
+      pac_content.contains("FindProxyForURL"),
+      "PAC file should contain FindProxyForURL function"
+    );
   }
 }
 
diff --git a/src-tauri/src/profile_importer.rs b/src-tauri/src/profile_importer.rs
index e6798da..e1db147 100644
--- a/src-tauri/src/profile_importer.rs
+++ b/src-tauri/src/profile_importer.rs
@@ -778,3 +778,206 @@ pub async fn import_browser_profile(
 lazy_static::lazy_static! {
   static ref PROFILE_IMPORTER: ProfileImporter = ProfileImporter::new();
 }
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+  use std::env;
+  use tempfile::TempDir;
+
+  fn create_test_profile_importer() -> (ProfileImporter, TempDir) {
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
+
+    // Set up a temporary home directory for testing
+    env::set_var("HOME", temp_dir.path());
+
+    let importer = ProfileImporter::new();
+    (importer, temp_dir)
+  }
+
+  #[test]
+  fn test_profile_importer_creation() {
+    let (_importer, _temp_dir) = create_test_profile_importer();
+    // Test passes if no panic occurs
+  }
+
+  #[test]
+  fn test_get_browser_display_name() {
+    let (importer, _temp_dir) = create_test_profile_importer();
+
+    assert_eq!(importer.get_browser_display_name("firefox"), "Firefox");
+    assert_eq!(
+      importer.get_browser_display_name("firefox-developer"),
+      "Firefox Developer"
+    );
+    assert_eq!(
+      importer.get_browser_display_name("chromium"),
+      "Chrome/Chromium"
+    );
+    assert_eq!(importer.get_browser_display_name("brave"), "Brave");
+    assert_eq!(
+      importer.get_browser_display_name("mullvad-browser"),
+      "Mullvad Browser"
+    );
+    assert_eq!(importer.get_browser_display_name("zen"), "Zen Browser");
+    assert_eq!(
+      importer.get_browser_display_name("tor-browser"),
+      "Tor Browser"
+    );
+    assert_eq!(
+      importer.get_browser_display_name("unknown"),
+      "Unknown Browser"
+    );
+  }
+
+  #[test]
+  fn test_detect_existing_profiles_no_panic() {
+    let (importer, _temp_dir) = create_test_profile_importer();
+
+    // This should not panic even if no browser profiles exist
+    let result = importer.detect_existing_profiles();
+    assert!(result.is_ok(), "detect_existing_profiles should not fail");
+
+    let _profiles = result.unwrap();
+    // We can't assert specific profiles since they depend on the system
+    // but we can verify the result is a valid Vec
+    // We can't assert specific profiles since they depend on the system
+    // but we can verify the result is a valid Vec (length check is always true for Vec, but shows intent)
+  }
+
+  #[test]
+  fn test_scan_firefox_profiles_dir_nonexistent() {
+    let (importer, temp_dir) = create_test_profile_importer();
+
+    let nonexistent_dir = temp_dir.path().join("nonexistent");
+    let result = importer.scan_firefox_profiles_dir(&nonexistent_dir, "firefox");
+
+    assert!(
+      result.is_ok(),
+      "Should handle nonexistent directory gracefully"
+    );
+    let profiles = result.unwrap();
+    assert!(
+      profiles.is_empty(),
+      "Should return empty vector for nonexistent directory"
+    );
+  }
+
+  #[test]
+  fn test_scan_chrome_profiles_dir_nonexistent() {
+    let (importer, temp_dir) = create_test_profile_importer();
+
+    let nonexistent_dir = temp_dir.path().join("nonexistent");
+    let result = importer.scan_chrome_profiles_dir(&nonexistent_dir, "chromium");
+
+    assert!(
+      result.is_ok(),
+      "Should handle nonexistent directory gracefully"
+    );
+    let profiles = result.unwrap();
+    assert!(
+      profiles.is_empty(),
+      "Should return empty vector for nonexistent directory"
+    );
+  }
+
+  #[test]
+  fn test_parse_firefox_profiles_ini_empty() {
+    let (importer, _temp_dir) = create_test_profile_importer();
+
+    let empty_content = "";
+    let profiles_dir = Path::new("/tmp");
+    let result = importer.parse_firefox_profiles_ini(empty_content, profiles_dir, "firefox");
+
+    assert!(result.is_ok(), "Should handle empty profiles.ini");
+    let profiles = result.unwrap();
+    assert!(
+      profiles.is_empty(),
+      "Should return empty vector for empty content"
+    );
+  }
+
+  #[test]
+  fn test_parse_firefox_profiles_ini_valid() {
+    let (importer, temp_dir) = create_test_profile_importer();
+
+    // Create a mock profile directory
+    let profiles_dir = temp_dir.path().join("profiles");
+    let profile_dir = profiles_dir.join("test.profile");
+    fs::create_dir_all(&profile_dir).expect("Should create profile directory");
+
+    // Create a prefs.js file to make it look like a valid profile
+    let prefs_file = profile_dir.join("prefs.js");
+    fs::write(&prefs_file, "// Firefox preferences").expect("Should create prefs.js");
+
+    let profiles_ini_content = r#"
+[Profile0]
+Name=Test Profile
+IsRelative=1
+Path=test.profile
+"#;
+
+    let result =
+      importer.parse_firefox_profiles_ini(profiles_ini_content, &profiles_dir, "firefox");
+
+    assert!(result.is_ok(), "Should parse valid profiles.ini");
+    let profiles = result.unwrap();
+    assert_eq!(profiles.len(), 1, "Should find one profile");
+    assert_eq!(profiles[0].name, "Firefox - Test Profile");
+    assert_eq!(profiles[0].browser, "firefox");
+  }
+
+  #[test]
+  fn test_copy_directory_recursive() {
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
+
+    // Create source directory structure
+    let source_dir = temp_dir.path().join("source");
+    let source_subdir = source_dir.join("subdir");
+    fs::create_dir_all(&source_subdir).expect("Should create source directories");
+
+    // Create some test files
+    let source_file1 = source_dir.join("file1.txt");
+    let source_file2 = source_subdir.join("file2.txt");
+    fs::write(&source_file1, "content1").expect("Should create file1");
+    fs::write(&source_file2, "content2").expect("Should create file2");
+
+    // Create destination directory
+    let dest_dir = temp_dir.path().join("dest");
+
+    // Copy recursively
+    let result = ProfileImporter::copy_directory_recursive(&source_dir, &dest_dir);
+    assert!(result.is_ok(), "Should copy directory successfully");
+
+    // Verify files were copied
+    let dest_file1 = dest_dir.join("file1.txt");
+    let dest_file2 = dest_dir.join("subdir").join("file2.txt");
+
+    assert!(dest_file1.exists(), "file1.txt should be copied");
+    assert!(dest_file2.exists(), "file2.txt should be copied");
+
+    let content1 = fs::read_to_string(&dest_file1).expect("Should read file1");
+    let content2 = fs::read_to_string(&dest_file2).expect("Should read file2");
+
+    assert_eq!(content1, "content1", "file1 content should match");
+    assert_eq!(content2, "content2", "file2 content should match");
+  }
+
+  #[test]
+  fn test_get_default_version_for_browser_no_versions() {
+    let (importer, _temp_dir) = create_test_profile_importer();
+
+    // This should fail since no versions are downloaded in test environment
+    let result = importer.get_default_version_for_browser("firefox");
+    assert!(
+      result.is_err(),
+      "Should fail when no versions are available"
+    );
+
+    let error_msg = result.unwrap_err().to_string();
+    assert!(
+      error_msg.contains("No downloaded versions found"),
+      "Error should mention no versions found"
+    );
+  }
+}
diff --git a/src-tauri/src/proxy_manager.rs b/src-tauri/src/proxy_manager.rs
index 0a281e0..3d2a553 100644
--- a/src-tauri/src/proxy_manager.rs
+++ b/src-tauri/src/proxy_manager.rs
@@ -573,8 +573,23 @@ mod tests {
       password: Some("pass".to_string()),
     };
 
-    assert!(!valid_settings.host.is_empty());
-    assert!(valid_settings.port > 0);
+    assert!(
+      !valid_settings.host.is_empty(),
+      "Valid settings should have non-empty host"
+    );
+    assert!(
+      valid_settings.port > 0,
+      "Valid settings should have positive port"
+    );
+    assert_eq!(valid_settings.proxy_type, "http", "Proxy type should match");
+    assert!(
+      valid_settings.username.is_some(),
+      "Username should be present"
+    );
+    assert!(
+      valid_settings.password.is_some(),
+      "Password should be present"
+    );
 
     // Test proxy settings with empty values
     let empty_settings = ProxySettings {
@@ -585,7 +600,16 @@ mod tests {
       password: None,
     };
 
-    assert!(empty_settings.host.is_empty());
+    assert!(
+      empty_settings.host.is_empty(),
+      "Empty settings should have empty host"
+    );
+    assert_eq!(
+      empty_settings.port, 0,
+      "Empty settings should have zero port"
+    );
+    assert!(empty_settings.username.is_none(), "Username should be None");
+    assert!(empty_settings.password.is_none(), "Password should be None");
   }
 
   #[tokio::test]
@@ -743,7 +767,7 @@ mod tests {
     };
 
     // Test command arguments match expected format
-    let _expected_args = [
+    let expected_args = [
       "proxy",
       "start",
       "--host",
@@ -759,11 +783,37 @@ mod tests {
     ];
 
     // This test verifies the argument structure without actually running the command
-    assert_eq!(proxy_settings.host, "proxy.example.com");
-    assert_eq!(proxy_settings.port, 8080);
-    assert_eq!(proxy_settings.proxy_type, "http");
-    assert_eq!(proxy_settings.username.as_ref().unwrap(), "user");
-    assert_eq!(proxy_settings.password.as_ref().unwrap(), "pass");
+    assert_eq!(
+      proxy_settings.host, "proxy.example.com",
+      "Host should match expected value"
+    );
+    assert_eq!(
+      proxy_settings.port, 8080,
+      "Port should match expected value"
+    );
+    assert_eq!(
+      proxy_settings.proxy_type, "http",
+      "Proxy type should match expected value"
+    );
+    assert_eq!(
+      proxy_settings.username.as_ref().unwrap(),
+      "user",
+      "Username should match expected value"
+    );
+    assert_eq!(
+      proxy_settings.password.as_ref().unwrap(),
+      "pass",
+      "Password should match expected value"
+    );
+
+    // Verify expected args structure
+    assert_eq!(expected_args[0], "proxy", "First arg should be 'proxy'");
+    assert_eq!(expected_args[1], "start", "Second arg should be 'start'");
+    assert_eq!(expected_args[2], "--host", "Third arg should be '--host'");
+    assert_eq!(
+      expected_args[3], "proxy.example.com",
+      "Fourth arg should be host value"
+    );
   }
 
   // Test the CLI detachment specifically - ensure the CLI exits properly
diff --git a/src-tauri/src/settings_manager.rs b/src-tauri/src/settings_manager.rs
index d66b0b3..ebb8f2d 100644
--- a/src-tauri/src/settings_manager.rs
+++ b/src-tauri/src/settings_manager.rs
@@ -245,3 +245,213 @@ pub async fn clear_all_version_cache_and_refetch(
 lazy_static::lazy_static! {
   static ref SETTINGS_MANAGER: SettingsManager = SettingsManager::new();
 }
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+  use std::env;
+  use tempfile::TempDir;
+
+  fn create_test_settings_manager() -> (SettingsManager, TempDir) {
+    let temp_dir = TempDir::new().expect("Failed to create temp directory");
+
+    // Set up a temporary home directory for testing
+    env::set_var("HOME", temp_dir.path());
+
+    let manager = SettingsManager::new();
+    (manager, temp_dir)
+  }
+
+  #[test]
+  fn test_settings_manager_creation() {
+    let (_manager, _temp_dir) = create_test_settings_manager();
+    // Test passes if no panic occurs
+  }
+
+  #[test]
+  fn test_default_app_settings() {
+    let default_settings = AppSettings::default();
+
+    assert!(
+      !default_settings.set_as_default_browser,
+      "Default should not set as default browser"
+    );
+    assert_eq!(
+      default_settings.theme, "system",
+      "Default theme should be system"
+    );
+  }
+
+  #[test]
+  fn test_default_table_sorting_settings() {
+    let default_sorting = TableSortingSettings::default();
+
+    assert_eq!(
+      default_sorting.column, "name",
+      "Default sort column should be name"
+    );
+    assert_eq!(
+      default_sorting.direction, "asc",
+      "Default sort direction should be asc"
+    );
+  }
+
+  #[test]
+  fn test_load_settings_nonexistent_file() {
+    let (manager, _temp_dir) = create_test_settings_manager();
+
+    let result = manager.load_settings();
+    assert!(
+      result.is_ok(),
+      "Should handle nonexistent settings file gracefully"
+    );
+
+    let settings = result.unwrap();
+    assert!(
+      !settings.set_as_default_browser,
+      "Should return default settings"
+    );
+    assert_eq!(settings.theme, "system", "Should return default theme");
+  }
+
+  #[test]
+  fn test_save_and_load_settings() {
+    let (manager, _temp_dir) = create_test_settings_manager();
+
+    let test_settings = AppSettings {
+      set_as_default_browser: true,
+      theme: "dark".to_string(),
+    };
+
+    // Save settings
+    let save_result = manager.save_settings(&test_settings);
+    assert!(save_result.is_ok(), "Should save settings successfully");
+
+    // Load settings back
+    let load_result = manager.load_settings();
+    assert!(load_result.is_ok(), "Should load settings successfully");
+
+    let loaded_settings = load_result.unwrap();
+    assert!(
+      loaded_settings.set_as_default_browser,
+      "Loaded settings should match saved"
+    );
+    assert_eq!(
+      loaded_settings.theme, "dark",
+      "Loaded theme should match saved"
+    );
+  }
+
+  #[test]
+  fn test_load_table_sorting_nonexistent_file() {
+    let (manager, _temp_dir) = create_test_settings_manager();
+
+    let result = manager.load_table_sorting();
+    assert!(
+      result.is_ok(),
+      "Should handle nonexistent sorting file gracefully"
+    );
+
+    let sorting = result.unwrap();
+    assert_eq!(sorting.column, "name", "Should return default sorting");
+    assert_eq!(sorting.direction, "asc", "Should return default direction");
+  }
+
+  #[test]
+  fn test_save_and_load_table_sorting() {
+    let (manager, _temp_dir) = create_test_settings_manager();
+
+    let test_sorting = TableSortingSettings {
+      column: "browser".to_string(),
+      direction: "desc".to_string(),
+    };
+
+    // Save sorting
+    let save_result = manager.save_table_sorting(&test_sorting);
+    assert!(save_result.is_ok(), "Should save sorting successfully");
+
+    // Load sorting back
+    let load_result = manager.load_table_sorting();
+    assert!(load_result.is_ok(), "Should load sorting successfully");
+
+    let loaded_sorting = load_result.unwrap();
+    assert_eq!(
+      loaded_sorting.column, "browser",
+      "Loaded column should match saved"
+    );
+    assert_eq!(
+      loaded_sorting.direction, "desc",
+      "Loaded direction should match saved"
+    );
+  }
+
+  #[test]
+  fn test_should_show_settings_on_startup() {
+    let (manager, _temp_dir) = create_test_settings_manager();
+
+    let result = manager.should_show_settings_on_startup();
+    assert!(result.is_ok(), "Should not fail");
+
+    let should_show = result.unwrap();
+    assert!(
+      !should_show,
+      "Should always return false as per implementation"
+    );
+  }
+
+  #[test]
+  fn test_load_corrupted_settings_file() {
+    let (manager, _temp_dir) = create_test_settings_manager();
+
+    // Create settings directory
+    let settings_dir = manager.get_settings_dir();
+    fs::create_dir_all(&settings_dir).expect("Should create settings directory");
+
+    // Write corrupted JSON
+    let settings_file = manager.get_settings_file();
+    fs::write(&settings_file, "{ invalid json }").expect("Should write corrupted file");
+
+    // Should handle corrupted file gracefully
+    let result = manager.load_settings();
+    assert!(
+      result.is_ok(),
+      "Should handle corrupted settings file gracefully"
+    );
+
+    let settings = result.unwrap();
+    assert!(
+      !settings.set_as_default_browser,
+      "Should return default settings for corrupted file"
+    );
+    assert_eq!(
+      settings.theme, "system",
+      "Should return default theme for corrupted file"
+    );
+  }
+
+  #[test]
+  fn test_settings_file_paths() {
+    let (manager, _temp_dir) = create_test_settings_manager();
+
+    let settings_dir = manager.get_settings_dir();
+    let settings_file = manager.get_settings_file();
+    let sorting_file = manager.get_table_sorting_file();
+
+    assert!(
+      settings_dir.to_string_lossy().contains("settings"),
+      "Settings dir should contain 'settings'"
+    );
+    assert!(
+      settings_file
+        .to_string_lossy()
+        .ends_with("app_settings.json"),
+      "Settings file should end with app_settings.json"
+    );
+    assert!(
+      sorting_file
+        .to_string_lossy()
+        .ends_with("table_sorting.json"),
+      "Sorting file should end with table_sorting.json"
+    );
+  }
+}
diff --git a/src-tauri/src/theme_detector.rs b/src-tauri/src/theme_detector.rs
index 3c1b7c1..7f6055e 100644
--- a/src-tauri/src/theme_detector.rs
+++ b/src-tauri/src/theme_detector.rs
@@ -529,16 +529,113 @@ mod tests {
   #[test]
   fn test_theme_detector_creation() {
     let detector = ThemeDetector::instance();
+
+    // Should not panic when creating detector
+    assert!(
+      std::ptr::eq(detector, ThemeDetector::instance()),
+      "Should return same instance (singleton)"
+    );
+  }
+
+  #[test]
+  fn test_detect_system_theme_returns_valid_value() {
+    let detector = ThemeDetector::instance();
     let theme = detector.detect_system_theme();
 
     // Should return a valid theme string
-    assert!(matches!(theme.theme.as_str(), "light" | "dark" | "unknown"));
+    assert!(
+      matches!(theme.theme.as_str(), "light" | "dark" | "unknown"),
+      "Theme should be one of: light, dark, unknown. Got: {}",
+      theme.theme
+    );
+
+    // Theme string should not be empty
+    assert!(!theme.theme.is_empty(), "Theme string should not be empty");
   }
 
   #[test]
   fn test_get_system_theme_command() {
     let theme = get_system_theme();
-    assert!(matches!(theme.theme.as_str(), "light" | "dark" | "unknown"));
+
+    assert!(
+      matches!(theme.theme.as_str(), "light" | "dark" | "unknown"),
+      "Command should return valid theme. Got: {}",
+      theme.theme
+    );
+
+    // Should be consistent with direct detector call
+    let detector = ThemeDetector::instance();
+    let direct_theme = detector.detect_system_theme();
+    assert_eq!(
+      theme.theme, direct_theme.theme,
+      "Command and direct call should return same theme"
+    );
+  }
+
+  #[test]
+  fn test_system_theme_serialization() {
+    let theme = SystemTheme {
+      theme: "dark".to_string(),
+    };
+
+    // Test serialization
+    let serialized = serde_json::to_string(&theme);
+    assert!(
+      serialized.is_ok(),
+      "Should serialize SystemTheme successfully"
+    );
+
+    let json_str = serialized.unwrap();
+    assert!(
+      json_str.contains("dark"),
+      "Serialized JSON should contain theme value"
+    );
+
+    // Test deserialization
+    let deserialized: Result<SystemTheme, _> = serde_json::from_str(&json_str);
+    assert!(
+      deserialized.is_ok(),
+      "Should deserialize SystemTheme successfully"
+    );
+
+    let theme_back = deserialized.unwrap();
+    assert_eq!(
+      theme_back.theme, "dark",
+      "Deserialized theme should match original"
+    );
+  }
+
+  #[cfg(target_os = "linux")]
+  #[test]
+  fn test_linux_command_availability_check() {
+    use super::linux::is_command_available;
+
+    // Test with a command that should exist on most systems
+    let ls_available = is_command_available("ls");
+    assert!(ls_available, "ls command should be available on Linux");
+
+    // Test with a command that definitely doesn't exist
+    let fake_available = is_command_available("definitely_nonexistent_command_12345");
+    assert!(!fake_available, "Fake command should not be available");
+  }
+
+  #[test]
+  fn test_theme_detector_consistency() {
+    let detector = ThemeDetector::instance();
+
+    // Call detect_system_theme multiple times - should be consistent
+    let theme1 = detector.detect_system_theme();
+    let theme2 = detector.detect_system_theme();
+    let theme3 = detector.detect_system_theme();
+
+    assert_eq!(
+      theme1.theme, theme2.theme,
+      "Multiple calls should return consistent results"
+    );
+    assert_eq!(
+      theme2.theme, theme3.theme,
+      "Multiple calls should return consistent results"
+    );
   }
 }
 
diff --git a/src-tauri/src/version_updater.rs b/src-tauri/src/version_updater.rs
index bf37f27..640880c 100644
--- a/src-tauri/src/version_updater.rs
+++ b/src-tauri/src/version_updater.rs
@@ -519,31 +519,152 @@ mod tests {
 
   #[test]
   fn test_should_run_background_update_logic() {
-    // Note: This test uses the shared state file, so results may vary
-    // depending on previous test runs. This is expected behavior.
+    // Create isolated test states to avoid interference
+    let current_time = VersionUpdater::get_current_timestamp();
 
     // Test with recent update (should not update)
     let recent_state = BackgroundUpdateState {
-      last_update_time: VersionUpdater::get_current_timestamp() - 60, // 1 minute ago
+      last_update_time: current_time - 60, // 1 minute ago
       update_interval_hours: 3,
     };
-    VersionUpdater::save_background_update_state(&recent_state).unwrap();
-    assert!(!VersionUpdater::should_run_background_update());
+
+    // Save and test recent state
+    let save_result = VersionUpdater::save_background_update_state(&recent_state);
+    assert!(save_result.is_ok(), "Should save recent state successfully");
+
+    let should_update_recent = VersionUpdater::should_run_background_update();
+    assert!(
+      !should_update_recent,
+      "Should not update when last update was recent"
+    );
 
     // Test with old update (should update)
     let old_state = BackgroundUpdateState {
-      last_update_time: VersionUpdater::get_current_timestamp() - (4 * 60 * 60), // 4 hours ago
+      last_update_time: current_time - (4 * 60 * 60), // 4 hours ago
       update_interval_hours: 3,
     };
-    VersionUpdater::save_background_update_state(&old_state).unwrap();
-    assert!(VersionUpdater::should_run_background_update());
+
+    // Save and test old state
+    let save_result = VersionUpdater::save_background_update_state(&old_state);
+    assert!(save_result.is_ok(), "Should save old state successfully");
+
+    let should_update_old = VersionUpdater::should_run_background_update();
+    assert!(should_update_old, "Should update when last update was old");
+
+    // Test with never updated (should update)
+    let never_updated_state = BackgroundUpdateState {
+      last_update_time: 0,
+      update_interval_hours: 3,
+    };
+
+    let save_result = VersionUpdater::save_background_update_state(&never_updated_state);
+    assert!(
+      save_result.is_ok(),
+      "Should save never updated state successfully"
+    );
+
+    let should_update_never = VersionUpdater::should_run_background_update();
+    assert!(
+      should_update_never,
+      "Should update when never updated before"
+    );
   }
 
   #[test]
   fn test_cache_dir_creation() {
     // This should not panic and should create the directory if it doesn't exist
-    let cache_dir = VersionUpdater::get_cache_dir().unwrap();
-    assert!(cache_dir.exists());
-    assert!(cache_dir.is_dir());
+    let cache_dir_result = VersionUpdater::get_cache_dir();
+    assert!(
+      cache_dir_result.is_ok(),
+      "Should successfully get cache directory"
+    );
+
+    let cache_dir = cache_dir_result.unwrap();
+    assert!(
+      cache_dir.exists(),
+      "Cache directory should exist after creation"
+    );
+    assert!(cache_dir.is_dir(), "Cache directory should be a directory");
+
+    // Verify the path contains expected components
+    let path_str = cache_dir.to_string_lossy();
+    assert!(
+      path_str.contains("version_cache"),
+      "Path should contain version_cache"
+    );
+
+    // Test that calling it again returns the same directory
+    let cache_dir2 = VersionUpdater::get_cache_dir().unwrap();
+    assert_eq!(
+      cache_dir, cache_dir2,
+      "Multiple calls should return same directory"
+    );
+  }
+
+  #[test]
+  fn test_version_updater_creation() {
+    let updater = VersionUpdater::new();
+
+    // Should have valid references to services
+    assert!(
+      !std::ptr::eq(updater.version_service as *const _, std::ptr::null()),
+      "Version service should not be null"
+    );
+    assert!(
+      !std::ptr::eq(updater.auto_updater as *const _, std::ptr::null()),
+      "Auto updater should not be null"
+    );
+    assert!(
+      updater.app_handle.is_none(),
+      "App handle should initially be None"
+    );
+  }
+
+  #[test]
+  fn test_get_current_timestamp() {
+    let timestamp1 = VersionUpdater::get_current_timestamp();
+
+    // Should be a reasonable timestamp (after year 2020)
+    assert!(
+      timestamp1 > 1577836800,
+      "Timestamp should be after 2020-01-01"
+    ); // 2020-01-01 00:00:00 UTC
+
+    // Should be before year 2100
+    assert!(
+      timestamp1 < 4102444800,
+      "Timestamp should be before 2100-01-01"
+    ); // 2100-01-01 00:00:00 UTC
+
+    // Wait a tiny bit and check it increases
+    std::thread::sleep(std::time::Duration::from_millis(1));
+    let timestamp2 = VersionUpdater::get_current_timestamp();
+    assert!(timestamp2 >= timestamp1, "Timestamp should not decrease");
+  }
+
+  #[test]
+  fn test_background_update_state_default() {
+    let state = BackgroundUpdateState::default();
+
+    assert_eq!(
+      state.last_update_time, 0,
+      "Default last update time should be 0"
+    );
+    assert_eq!(
+      state.update_interval_hours, 3,
+      "Default update interval should be 3 hours"
+    );
+  }
+
+  #[test]
+  fn test_get_version_updater_singleton() {
+    let updater1 = get_version_updater();
+    let updater2 = get_version_updater();
+
+    // Should return the same Arc instance
+    assert!(
+      Arc::ptr_eq(&updater1, &updater2),
+      "Should return same singleton instance"
+    );
   }
 }