Auto merge of #23559 - jdm:uwp-dirs, r=asajeffrey

Remove dirs crate from use in UWP builds.

The dirs crate relies on APIs that aren't available to UWP apps. This adds the ability to hide it from builds that need to run in UWP environments.

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components/config/Cargo.toml

@@ -6,6 +6,9 @@ license = "MPL-2.0"
 edition = "2018"
 publish = false
 
+[features]
+uwp = []
+
 [lib]
 name = "servo_config"
 path = "lib.rs"
@@ -29,5 +32,5 @@ servo_config_plugins = { path = "../config_plugins" }
 env_logger = "0.6"
 std_test_override = { path = "../std_test_override" }
 
-[target.'cfg(not(target_os = "android"))'.dependencies]
+[target.'cfg(not(any(target_os = "android", feature = "uwp")))'.dependencies]
 dirs = "1.0"

components/config/basedir.rs

@@ -35,9 +35,14 @@ pub fn default_config_dir() -> Option<PathBuf> {
     Some(config_dir)
 }
 
-#[cfg(target_os = "windows")]
+#[cfg(all(target_os = "windows", not(feature = "uwp")))]
 pub fn default_config_dir() -> Option<PathBuf> {
     let mut config_dir = ::dirs::config_dir().unwrap();
     config_dir.push("Servo");
     Some(config_dir)
 }
+
+#[cfg(all(target_os = "windows", feature = "uwp"))]
+pub fn default_config_dir() -> Option<PathBuf> {
+    None
+}

components/config/prefs.rs

@@ -58,7 +58,7 @@ pub fn pref_map() -> &'static Preferences<'static, Prefs> {
     &PREFS
 }
 
-pub fn add_user_prefs() {
+pub(crate) fn add_user_prefs() {
     if let Some(path) = user_prefs_path() {
         init_user_prefs(path);
     }

components/config/tests/prefs.rs

@@ -244,7 +244,7 @@ fn test_set_all_error_on_unknown_field() -> Result<(), Box<dyn Error>> {
     Ok(())
 }
 
-#[cfg(not(target_os = "android"))]
+#[cfg(not(any(target_os = "android", feature = "uwp")))]
 #[test]
 fn test_default_config_dir_create_read_write() {
     let json_str = "{\

components/servo/Cargo.toml

@@ -22,6 +22,7 @@ max_log_level = ["log/release_max_level_info"]
 native-bluetooth = ["bluetooth/native-bluetooth"]
 no_wgl = ["canvas/no_wgl"]
 raqote_backend = ["canvas/raqote_backend"]
+uwp = ["servo_config/uwp"]
 webrender_debugger = ["webrender/debugger"]
 no_static_freetype = ["webrender/no_static_freetype"]
 oculusvr = ["webvr/oculusvr"]

ports/libsimpleservo/api/Cargo.toml

@@ -41,4 +41,5 @@ oculusvr = ["libservo/oculusvr"]
 raqote_backend = ["libservo/raqote_backend"]
 webdriver = ["libservo/webdriver"]
 unstable = ["libservo/unstable"]
+uwp = ["libservo/uwp"]
 webgl_backtrace = ["libservo/webgl_backtrace"]

ports/libsimpleservo/capi/Cargo.toml

@@ -34,5 +34,6 @@ no_wgl = ["simpleservo/no_wgl"]
 oculusvr = ["simpleservo/oculusvr"]
 raqote_backend = ["simpleservo/raqote_backend"]
 unstable = ["simpleservo/unstable"]
+uwp = ["simpleservo/uwp"]
 webdriver = ["simpleservo/webdriver"]
 webgl_backtrace = ["simpleservo/webgl_backtrace"]