From 04094ced84a95ebebedfc287533d110094a3ea53 Mon Sep 17 00:00:00 2001
From: Alexandre Lissy <lissyx+mozillians@lissyx.dyndns.org>
Date: Thu, 3 Apr 2025 16:10:43 +0000
Subject: [PATCH] Bug 1725134 - Handle XDG_CONFIG_HOME in crashreporter
 r=afranchuk

Differential Revision: https://phabricator.services.mozilla.com/D122358
---
 .../crashreporter/client/app/src/config.rs    | 64 +++++++++++++++++--
 .../crashreporter/client/app/src/std/env.rs   | 22 +++++--
 2 files changed, 77 insertions(+), 9 deletions(-)

diff --git a/toolkit/crashreporter/client/app/src/config.rs b/toolkit/crashreporter/client/app/src/config.rs
index d1103541751f..999b1d623326 100644
--- a/toolkit/crashreporter/client/app/src/config.rs
+++ b/toolkit/crashreporter/client/app/src/config.rs
@@ -17,6 +17,48 @@ const MINIDUMP_PRUNE_SAVE_COUNT: usize = 10;
 #[cfg(test)]
 pub mod test {
     pub const MINIDUMP_PRUNE_SAVE_COUNT: usize = super::MINIDUMP_PRUNE_SAVE_COUNT;
+
+    cfg_if::cfg_if! {
+        if #[cfg(target_os = "linux")] {
+            use crate::std::{mock, env};
+
+            fn cfg_get_data_dir_root() -> crate::std::path::PathBuf {
+                let cfg = super::Config::new();
+                cfg.get_data_dir_root("vendor").unwrap()
+            }
+
+            #[test]
+            fn data_dir_root_xdg_default() {
+                mock::builder()
+                    .set(env::MockHomeDir, "home_dir".into())
+                    .run(|| {
+                        let path = cfg_get_data_dir_root();
+                        assert_eq!(path, crate::std::path::PathBuf::from("home_dir/.config/vendor"));
+                     });
+            }
+
+            #[test]
+            fn data_dir_root_xdg_home() {
+                mock::builder()
+                    .set(env::MockEnv("XDG_CONFIG_HOME".into()), "home_dir/xdg/config".into())
+                    .run(|| {
+                        let path = cfg_get_data_dir_root();
+                        assert_eq!(path, crate::std::path::PathBuf::from("home_dir/xdg/config/vendor"));
+                    });
+            }
+
+            #[test]
+            fn data_dir_root_legacy_force() {
+                mock::builder()
+                    .set(env::MockHomeDir, "home_dir".into())
+                    .set(env::MockEnv("MOZ_LEGACY_HOME".into()), "1".into())
+                    .run(|| {
+                        let path = cfg_get_data_dir_root();
+                        assert_eq!(path, crate::std::path::PathBuf::from("home_dir/.vendor"));
+                    });
+            }
+        }
+    }
 }
 
 mod buildid_section {
@@ -428,6 +470,22 @@ impl Config {
         }
     }
 
+    #[cfg(target_os = "linux")]
+    fn get_data_dir_root(&self, vendor: &str) -> anyhow::Result<PathBuf> {
+        // home_dir is deprecated due to incorrect behavior on windows, but we only use it on linux
+        #[allow(deprecated)]
+        let data_path = if std::env::var_os("MOZ_LEGACY_HOME").is_some() {
+            std::env::home_dir().map(|h| h.join(format!(".{}", vendor.to_lowercase())))
+        } else {
+            std::env::var_os("XDG_CONFIG_HOME")
+                .map(PathBuf::from)
+                .or_else(|| std::env::home_dir().map(|home| home.join(".config")))
+                .map(|h| h.join(format!("{}", vendor.to_lowercase())))
+        }
+        .with_context(|| self.string("crashreporter-error-no-home-dir"))?;
+        Ok(data_path)
+    }
+
     cfg_if::cfg_if! {
         if #[cfg(mock)] {
             fn get_data_dir(&self, vendor: &str, product: &str) -> anyhow::Result<PathBuf> {
@@ -439,11 +497,7 @@ impl Config {
             }
         } else if #[cfg(target_os = "linux")] {
             fn get_data_dir(&self, vendor: &str, product: &str) -> anyhow::Result<PathBuf> {
-                // home_dir is deprecated due to incorrect behavior on windows, but we only use it on linux
-                #[allow(deprecated)]
-                let mut data_path =
-                    std::env::home_dir().with_context(|| self.string("crashreporter-error-no-home-dir"))?;
-                data_path.push(format!(".{}", vendor.to_lowercase()));
+            let mut data_path = self.get_data_dir_root(vendor)?;
                 data_path.push(product.to_lowercase());
                 data_path.push("Crash Reports");
                 Ok(data_path)
diff --git a/toolkit/crashreporter/client/app/src/std/env.rs b/toolkit/crashreporter/client/app/src/std/env.rs
index 77d9d4aecc58..b135a1b7db4d 100644
--- a/toolkit/crashreporter/client/app/src/std/env.rs
+++ b/toolkit/crashreporter/client/app/src/std/env.rs
@@ -10,6 +10,14 @@ mock_key! {
     pub struct MockCurrentExe => std::path::PathBuf
 }
 
+mock_key! {
+    pub struct MockEnv(pub OsString) => String
+}
+
+mock_key! {
+    pub struct MockHomeDir => super::path::PathBuf
+}
+
 pub struct ArgsOs {
     argv0: Option<OsString>,
 }
@@ -26,12 +34,14 @@ impl Iterator for ArgsOs {
     }
 }
 
-pub fn var<K: AsRef<OsStr>>(_key: K) -> Result<String, VarError> {
-    unimplemented!("no var access in tests")
+pub fn var<K: AsRef<OsStr>>(key: K) -> Result<String, VarError> {
+    MockEnv(key.as_ref().to_os_string())
+        .try_get(|value| value.clone())
+        .ok_or(VarError::NotPresent)
 }
 
-pub fn var_os<K: AsRef<OsStr>>(_key: K) -> Option<OsString> {
-    unimplemented!("no var access in tests")
+pub fn var_os<K: AsRef<OsStr>>(key: K) -> Option<OsString> {
+    MockEnv(key.as_ref().to_os_string()).try_get(|value| value.clone().into())
 }
 
 pub fn args_os() -> ArgsOs {
@@ -40,6 +50,10 @@ pub fn args_os() -> ArgsOs {
     })
 }
 
+pub fn home_dir() -> Option<super::path::PathBuf> {
+    MockHomeDir.try_get(|p| p.clone())
+}
+
 #[allow(unused)]
 pub fn current_exe() -> std::io::Result<super::path::PathBuf> {
     Ok(MockCurrentExe.get(|r| r.clone().into()))