From 2d9b2f16d938e1a4a391534df37f99f1c64c8ea6 Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 11:02:22 +0100
Subject: [PATCH 01/14] fix typo in docs

---
 git-discover/src/repository.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/git-discover/src/repository.rs b/git-discover/src/repository.rs
index 25c0730d304..0d6cf060bb1 100644
--- a/git-discover/src/repository.rs
+++ b/git-discover/src/repository.rs
@@ -116,7 +116,7 @@ pub enum Kind {
     ///
     /// Note that this is merely a guess at this point as we didn't read the configuration yet.
     Bare,
-    /// A `git` repository along with a checked out files in a work tree.
+    /// A `git` repository along with checked out files in a work tree.
     WorkTree {
         /// If set, this is the git dir associated with this _linked_ worktree.
         /// If `None`, the git_dir is the `.git` directory inside the _main_ worktree we represent.

From 23d847480eff1a0d26fd801dfa8ad6ed205c71d4 Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 11:02:41 +0100
Subject: [PATCH 02/14] add test for worktree configs

---
 .../make_worktree_repo_with_configs.tar.xz    |  3 ++
 .../make_worktree_repo_with_configs.sh        | 25 ++++++++++
 git-repository/tests/repository/config/mod.rs |  1 +
 .../tests/repository/config/worktree.rs       | 48 +++++++++++++++++++
 4 files changed, 77 insertions(+)
 create mode 100644 git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz
 create mode 100644 git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
 create mode 100644 git-repository/tests/repository/config/worktree.rs

diff --git a/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz b/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz
new file mode 100644
index 00000000000..8a3d24f6b01
--- /dev/null
+++ b/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:ea82cbcda5a07a6e7ddde7d9e3834d1ec7e184811ccab29c7ea21d9a53705f1f
+size 10564
diff --git a/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh b/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
new file mode 100644
index 00000000000..d3960b4cb25
--- /dev/null
+++ b/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
@@ -0,0 +1,25 @@
+#!/bin/bash
+
+set -eu -o pipefail
+
+git init repo
+
+(cd repo
+  touch a b c
+  git add .
+  git commit -m initial
+
+  git worktree add ../wt-1
+  git worktree add ../wt-2
+
+  git config extensions.worktreeConfig true
+  git config --worktree worktree.setting "set in the main worktree"
+)
+
+(cd wt-1
+  git config --worktree worktree.setting "set in wt-1"
+)
+
+(cd wt-2
+  git config --worktree worktree.setting "set in wt-2"
+)
diff --git a/git-repository/tests/repository/config/mod.rs b/git-repository/tests/repository/config/mod.rs
index 5b82895d3af..5465c7fa2fd 100644
--- a/git-repository/tests/repository/config/mod.rs
+++ b/git-repository/tests/repository/config/mod.rs
@@ -3,3 +3,4 @@ mod identity;
 mod remote;
 #[cfg(any(feature = "blocking-network-client", feature = "async-network-client"))]
 mod transport_options;
+mod worktree;
diff --git a/git-repository/tests/repository/config/worktree.rs b/git-repository/tests/repository/config/worktree.rs
new file mode 100644
index 00000000000..1b744df0c15
--- /dev/null
+++ b/git-repository/tests/repository/config/worktree.rs
@@ -0,0 +1,48 @@
+use git_repository::open;
+
+#[test]
+fn with_worktree_configs() -> git_testtools::Result {
+    let dir = git_testtools::scripted_fixture_repo_read_only("make_worktree_repo_with_configs.sh").unwrap();
+
+    let base = open(dir.join("repo")).unwrap();
+    let base_config = base.config_snapshot();
+
+    assert_eq!(base.work_dir(), Some(dir.join("repo").as_path()));
+    assert_eq!(base.git_dir(), dir.join("repo/.git"));
+    assert_eq!(base.common_dir(), dir.join("repo/.git"));
+
+    assert_eq!(
+        base_config.string("worktree.setting").expect("exists").to_string(),
+        "set in the main worktree"
+    );
+
+    let wt1 = open(dir.join("wt-1")).unwrap();
+    let wt1_config = wt1.config_snapshot();
+    assert_eq!(wt1.work_dir(), Some(dir.join("wt-1").as_path()));
+    assert_eq!(wt1.git_dir(), dir.join("repo/.git/worktrees/wt-1").canonicalize()?);
+    assert_eq!(
+        wt1.common_dir(),
+        dir.join("repo/.git").canonicalize()?.join("worktrees/wt-1/../..")
+    );
+
+    assert_eq!(
+        wt1_config.string("worktree.setting").expect("exists").to_string(),
+        "set in wt-1"
+    );
+
+    let wt2 = open(dir.join("wt-2")).unwrap();
+    let wt2_config = wt2.config_snapshot();
+    assert_eq!(wt2.work_dir(), Some(dir.join("wt-2").as_path()));
+    assert_eq!(wt2.git_dir(), dir.join("repo/.git/worktrees/wt-2").canonicalize()?);
+    assert_eq!(
+        wt2.common_dir(),
+        dir.join("repo/.git").canonicalize()?.join("worktrees/wt-2/../..")
+    );
+
+    assert_eq!(
+        wt2_config.string("worktree.setting").expect("exists").to_string(),
+        "set in wt-2"
+    );
+
+    Ok(())
+}

From 760e736931c13d155dbbe46459fe11b602084549 Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 11:07:47 +0100
Subject: [PATCH 03/14] load worktree config if necessary

---
 git-repository/src/config/cache/incubate.rs | 44 ++++++++++++++-------
 git-repository/src/open/repository.rs       |  8 +++-
 2 files changed, 36 insertions(+), 16 deletions(-)

diff --git a/git-repository/src/config/cache/incubate.rs b/git-repository/src/config/cache/incubate.rs
index 233b4c0f3e6..401afccd0aa 100644
--- a/git-repository/src/config/cache/incubate.rs
+++ b/git-repository/src/config/cache/incubate.rs
@@ -15,27 +15,14 @@ pub(crate) struct StageOne {
 /// Initialization
 impl StageOne {
     pub fn new(
+        common_dir: &std::path::Path,
         git_dir: &std::path::Path,
         git_dir_trust: git_sec::Trust,
         lossy: Option<bool>,
         lenient: bool,
     ) -> Result<Self, Error> {
         let mut buf = Vec::with_capacity(512);
-        let config = {
-            let config_path = git_dir.join("config");
-            std::io::copy(&mut std::fs::File::open(&config_path)?, &mut buf)?;
-
-            git_config::File::from_bytes_owned(
-                &mut buf,
-                git_config::file::Metadata::from(git_config::Source::Local)
-                    .at(config_path)
-                    .with(git_dir_trust),
-                git_config::file::init::Options {
-                    includes: git_config::file::includes::Options::no_follow(),
-                    ..util::base_options(lossy)
-                },
-            )?
-        };
+        let mut config = load_config(&mut buf, common_dir.join("config"), git_dir_trust, lossy)?;
 
         let is_bare = util::config_bool(&config, "core.bare", false, lenient)?;
         let repo_format_version = config
@@ -57,6 +44,11 @@ impl StageOne {
             .transpose()?
             .unwrap_or(git_hash::Kind::Sha1);
 
+        if util::config_bool(&config, "extensions.worktreeConfig", false, lenient)? {
+            let wt_config = load_config(&mut buf, git_dir.join("config.worktree"), git_dir_trust, lossy)?;
+            config.append(wt_config);
+        }
+
         let reflog = util::query_refupdates(&config, lenient)?;
         Ok(StageOne {
             git_dir_config: config,
@@ -68,3 +60,25 @@ impl StageOne {
         })
     }
 }
+
+fn load_config(
+    buf: &mut Vec<u8>,
+    config_path: std::path::PathBuf,
+    git_dir_trust: git_sec::Trust,
+    lossy: Option<bool>,
+) -> Result<git_config::File<'static>, Error> {
+    std::io::copy(&mut std::fs::File::open(&config_path)?, buf)?;
+
+    let config = git_config::File::from_bytes_owned(
+        buf,
+        git_config::file::Metadata::from(git_config::Source::Worktree)
+            .at(config_path)
+            .with(git_dir_trust),
+        git_config::file::init::Options {
+            includes: git_config::file::includes::Options::no_follow(),
+            ..util::base_options(lossy)
+        },
+    )?;
+
+    Ok(config)
+}
diff --git a/git-repository/src/open/repository.rs b/git-repository/src/open/repository.rs
index b3a14f92571..5953a54f440 100644
--- a/git-repository/src/open/repository.rs
+++ b/git-repository/src/open/repository.rs
@@ -133,7 +133,13 @@ impl ThreadSafeRepository {
             .map(|cd| git_dir.join(cd));
         let common_dir_ref = common_dir.as_deref().unwrap_or(&git_dir);
 
-        let repo_config = config::cache::StageOne::new(common_dir_ref, git_dir_trust, lossy_config, lenient_config)?;
+        let repo_config = config::cache::StageOne::new(
+            common_dir_ref,
+            git_dir.as_ref(),
+            git_dir_trust,
+            lossy_config,
+            lenient_config,
+        )?;
         let mut refs = {
             let reflog = repo_config.reflog.unwrap_or(git_ref::store::WriteReflog::Disable);
             let object_hash = repo_config.object_hash;

From 7ebf229bec6075a149702273c86137f54ef721ed Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 11:08:21 +0100
Subject: [PATCH 04/14] =?UTF-8?q?remove=20worktree=20permission=20configur?=
 =?UTF-8?q?ation=20option=E2=80=A6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

…if worktree configs exist they should always be read
---
 git-repository/src/repository/permissions.rs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/git-repository/src/repository/permissions.rs b/git-repository/src/repository/permissions.rs
index aab98c6799b..970add1058c 100644
--- a/git-repository/src/repository/permissions.rs
+++ b/git-repository/src/repository/permissions.rs
@@ -29,9 +29,6 @@ pub struct Config {
     /// Whether to use the user configuration.
     /// This is usually `~/.gitconfig` on unix.
     pub user: bool,
-    // TODO: figure out how this really applies and provide more information here.
-    // Whether to use worktree configuration from `config.worktree`.
-    // pub worktree: bool,
     /// Whether to use the configuration from environment variables.
     pub env: bool,
     /// Whether to follow include files are encountered in loaded configuration,

From 394aab90bdcaa1683b0318e70c455d09b1a7d4cc Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 11:17:40 +0100
Subject: [PATCH 05/14] =?UTF-8?q?refactor=E2=80=A6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

…reuse buffer instead of appending configs
---
 git-repository/src/config/cache/incubate.rs | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/git-repository/src/config/cache/incubate.rs b/git-repository/src/config/cache/incubate.rs
index 401afccd0aa..c516e5d3ec6 100644
--- a/git-repository/src/config/cache/incubate.rs
+++ b/git-repository/src/config/cache/incubate.rs
@@ -22,7 +22,7 @@ impl StageOne {
         lenient: bool,
     ) -> Result<Self, Error> {
         let mut buf = Vec::with_capacity(512);
-        let mut config = load_config(&mut buf, common_dir.join("config"), git_dir_trust, lossy)?;
+        let config = load_config(&mut buf, common_dir.join("config"), git_dir_trust, lossy)?;
 
         let is_bare = util::config_bool(&config, "core.bare", false, lenient)?;
         let repo_format_version = config
@@ -44,10 +44,12 @@ impl StageOne {
             .transpose()?
             .unwrap_or(git_hash::Kind::Sha1);
 
-        if util::config_bool(&config, "extensions.worktreeConfig", false, lenient)? {
-            let wt_config = load_config(&mut buf, git_dir.join("config.worktree"), git_dir_trust, lossy)?;
-            config.append(wt_config);
-        }
+        let extension_worktree = util::config_bool(&config, "extensions.worktreeConfig", false, lenient)?;
+        let config = if extension_worktree {
+            load_config(&mut buf, git_dir.join("config.worktree"), git_dir_trust, lossy)?
+        } else {
+            config
+        };
 
         let reflog = util::query_refupdates(&config, lenient)?;
         Ok(StageOne {

From ae812bde55d55ce06f95ca73513d9749e876ea0e Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 11:28:13 +0100
Subject: [PATCH 06/14] =?UTF-8?q?refactor=E2=80=A6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

…add shared config entry to the fixture and check it in tests
---
 .../make_worktree_repo_with_configs.tar.xz           |  4 ++--
 .../fixtures/make_worktree_repo_with_configs.sh      |  2 ++
 git-repository/tests/repository/config/worktree.rs   | 12 ++++++++++++
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz b/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz
index 8a3d24f6b01..9b1344fbf5a 100644
--- a/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz
+++ b/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:ea82cbcda5a07a6e7ddde7d9e3834d1ec7e184811ccab29c7ea21d9a53705f1f
-size 10564
+oid sha256:611d290ed94289d6ed037e1ba6edfb49cdd007fb4c478147bd10f90a7ef2c515
+size 10576
diff --git a/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh b/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
index d3960b4cb25..f7bc178fe17 100644
--- a/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
+++ b/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
@@ -14,6 +14,8 @@ git init repo
 
   git config extensions.worktreeConfig true
   git config --worktree worktree.setting "set in the main worktree"
+
+  git config shared.setting "set in the shared config"
 )
 
 (cd wt-1
diff --git a/git-repository/tests/repository/config/worktree.rs b/git-repository/tests/repository/config/worktree.rs
index 1b744df0c15..7ab707eb129 100644
--- a/git-repository/tests/repository/config/worktree.rs
+++ b/git-repository/tests/repository/config/worktree.rs
@@ -15,6 +15,10 @@ fn with_worktree_configs() -> git_testtools::Result {
         base_config.string("worktree.setting").expect("exists").to_string(),
         "set in the main worktree"
     );
+    assert_eq!(
+        base_config.string("shared.setting").expect("exists").to_string(),
+        "set in the shared config"
+    );
 
     let wt1 = open(dir.join("wt-1")).unwrap();
     let wt1_config = wt1.config_snapshot();
@@ -29,6 +33,10 @@ fn with_worktree_configs() -> git_testtools::Result {
         wt1_config.string("worktree.setting").expect("exists").to_string(),
         "set in wt-1"
     );
+    assert_eq!(
+        wt1_config.string("shared.setting").expect("exists").to_string(),
+        "set in the shared config"
+    );
 
     let wt2 = open(dir.join("wt-2")).unwrap();
     let wt2_config = wt2.config_snapshot();
@@ -43,6 +51,10 @@ fn with_worktree_configs() -> git_testtools::Result {
         wt2_config.string("worktree.setting").expect("exists").to_string(),
         "set in wt-2"
     );
+    assert_eq!(
+        wt2_config.string("shared.setting").expect("exists").to_string(),
+        "set in the shared config"
+    );
 
     Ok(())
 }

From 5c2b44c53feae9f23c715dbad962baaf64135963 Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 12:55:03 +0100
Subject: [PATCH 07/14] =?UTF-8?q?exclude=20fixture=20archive=20from=20bein?=
 =?UTF-8?q?g=20uploaded=E2=80=A6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

…because creating worktrees with `git` creates a .git file in the worktree
that points to the git_dir using an absolute path, so every tester has to
generate that fixture from scratch.
---
 git-repository/tests/fixtures/generated-archives/.gitignore    | 1 +
 .../generated-archives/make_worktree_repo_with_configs.tar.xz  | 3 ---
 2 files changed, 1 insertion(+), 3 deletions(-)
 delete mode 100644 git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz

diff --git a/git-repository/tests/fixtures/generated-archives/.gitignore b/git-repository/tests/fixtures/generated-archives/.gitignore
index 9f4f7db5774..0a5636787b7 100644
--- a/git-repository/tests/fixtures/generated-archives/.gitignore
+++ b/git-repository/tests/fixtures/generated-archives/.gitignore
@@ -1,4 +1,5 @@
 /make_worktree_repo.tar.xz
+/make_worktree_repo_with_configs.tar
 /make_remote_repos.tar.xz
 /make_fetch_repos.tar.xz
 /make_core_worktree_repo.tar.xz
diff --git a/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz b/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz
deleted file mode 100644
index 9b1344fbf5a..00000000000
--- a/git-repository/tests/fixtures/generated-archives/make_worktree_repo_with_configs.tar.xz
+++ /dev/null
@@ -1,3 +0,0 @@
-version https://git-lfs.github.com/spec/v1
-oid sha256:611d290ed94289d6ed037e1ba6edfb49cdd007fb4c478147bd10f90a7ef2c515
-size 10576

From 33992ab6510c65dc97e5eb9565141b977f5b021f Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 13:13:01 +0100
Subject: [PATCH 08/14] fix type - prevent creating a fixture archive

---
 git-repository/tests/fixtures/generated-archives/.gitignore | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/git-repository/tests/fixtures/generated-archives/.gitignore b/git-repository/tests/fixtures/generated-archives/.gitignore
index 0a5636787b7..8895a24ab87 100644
--- a/git-repository/tests/fixtures/generated-archives/.gitignore
+++ b/git-repository/tests/fixtures/generated-archives/.gitignore
@@ -1,5 +1,5 @@
 /make_worktree_repo.tar.xz
-/make_worktree_repo_with_configs.tar
+/make_worktree_repo_with_configs.tar.xz
 /make_remote_repos.tar.xz
 /make_fetch_repos.tar.xz
 /make_core_worktree_repo.tar.xz

From bea689a97a8e42a92af7f77f7d8706cd96c6dc10 Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Thu, 1 Dec 2022 14:12:42 +0100
Subject: [PATCH 09/14] =?UTF-8?q?remove=20`canonicalize`=20calls=20from=20?=
 =?UTF-8?q?test=E2=80=A6?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

…and use CARGO_MANIFEST_DIR instead
---
 .../tests/repository/config/worktree.rs       | 34 ++++++++++++-------
 1 file changed, 21 insertions(+), 13 deletions(-)

diff --git a/git-repository/tests/repository/config/worktree.rs b/git-repository/tests/repository/config/worktree.rs
index 7ab707eb129..81fdebf92f7 100644
--- a/git-repository/tests/repository/config/worktree.rs
+++ b/git-repository/tests/repository/config/worktree.rs
@@ -2,14 +2,16 @@ use git_repository::open;
 
 #[test]
 fn with_worktree_configs() -> git_testtools::Result {
-    let dir = git_testtools::scripted_fixture_repo_read_only("make_worktree_repo_with_configs.sh").unwrap();
+    let manifest_dir = std::path::PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
 
-    let base = open(dir.join("repo")).unwrap();
+    let fixture_dir = git_testtools::scripted_fixture_repo_read_only("make_worktree_repo_with_configs.sh").unwrap();
+
+    let base = open(fixture_dir.join("repo")).unwrap();
     let base_config = base.config_snapshot();
 
-    assert_eq!(base.work_dir(), Some(dir.join("repo").as_path()));
-    assert_eq!(base.git_dir(), dir.join("repo/.git"));
-    assert_eq!(base.common_dir(), dir.join("repo/.git"));
+    assert_eq!(base.work_dir(), Some(fixture_dir.join("repo").as_path()));
+    assert_eq!(base.git_dir(), fixture_dir.join("repo/.git"));
+    assert_eq!(base.common_dir(), fixture_dir.join("repo/.git"));
 
     assert_eq!(
         base_config.string("worktree.setting").expect("exists").to_string(),
@@ -20,13 +22,16 @@ fn with_worktree_configs() -> git_testtools::Result {
         "set in the shared config"
     );
 
-    let wt1 = open(dir.join("wt-1")).unwrap();
+    let wt1 = open(fixture_dir.join("wt-1")).unwrap();
     let wt1_config = wt1.config_snapshot();
-    assert_eq!(wt1.work_dir(), Some(dir.join("wt-1").as_path()));
-    assert_eq!(wt1.git_dir(), dir.join("repo/.git/worktrees/wt-1").canonicalize()?);
+    assert_eq!(wt1.work_dir(), Some(fixture_dir.join("wt-1").as_path()));
+    assert_eq!(
+        wt1.git_dir(),
+        manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-1")
+    );
     assert_eq!(
         wt1.common_dir(),
-        dir.join("repo/.git").canonicalize()?.join("worktrees/wt-1/../..")
+        manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-1/../..")
     );
 
     assert_eq!(
@@ -38,13 +43,16 @@ fn with_worktree_configs() -> git_testtools::Result {
         "set in the shared config"
     );
 
-    let wt2 = open(dir.join("wt-2")).unwrap();
+    let wt2 = open(fixture_dir.join("wt-2")).unwrap();
     let wt2_config = wt2.config_snapshot();
-    assert_eq!(wt2.work_dir(), Some(dir.join("wt-2").as_path()));
-    assert_eq!(wt2.git_dir(), dir.join("repo/.git/worktrees/wt-2").canonicalize()?);
+    assert_eq!(wt2.work_dir(), Some(fixture_dir.join("wt-2").as_path()));
+    assert_eq!(
+        wt2.git_dir(),
+        manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-2")
+    );
     assert_eq!(
         wt2.common_dir(),
-        dir.join("repo/.git").canonicalize()?.join("worktrees/wt-2/../..")
+        manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-2/../..")
     );
 
     assert_eq!(

From b69f21997bac7751e879608fe5b0ba08814aab4d Mon Sep 17 00:00:00 2001
From: Sidney Douw <s.douw@gmx.de>
Date: Fri, 2 Dec 2022 18:14:24 +0100
Subject: [PATCH 10/14] test to check if worktree overrides shared configs

---
 .../fixtures/make_worktree_repo_with_configs.sh      |  2 ++
 git-repository/tests/repository/config/worktree.rs   | 12 ++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh b/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
index f7bc178fe17..f1c046d7987 100644
--- a/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
+++ b/git-repository/tests/fixtures/make_worktree_repo_with_configs.sh
@@ -16,6 +16,7 @@ git init repo
   git config --worktree worktree.setting "set in the main worktree"
 
   git config shared.setting "set in the shared config"
+  git config override.setting "set in the shared config"
 )
 
 (cd wt-1
@@ -24,4 +25,5 @@ git init repo
 
 (cd wt-2
   git config --worktree worktree.setting "set in wt-2"
+  git config --worktree override.setting "override in wt-2"
 )
diff --git a/git-repository/tests/repository/config/worktree.rs b/git-repository/tests/repository/config/worktree.rs
index 81fdebf92f7..af047b0e810 100644
--- a/git-repository/tests/repository/config/worktree.rs
+++ b/git-repository/tests/repository/config/worktree.rs
@@ -21,6 +21,10 @@ fn with_worktree_configs() -> git_testtools::Result {
         base_config.string("shared.setting").expect("exists").to_string(),
         "set in the shared config"
     );
+    assert_eq!(
+        base_config.string("override.setting").expect("exists").to_string(),
+        "set in the shared config"
+    );
 
     let wt1 = open(fixture_dir.join("wt-1")).unwrap();
     let wt1_config = wt1.config_snapshot();
@@ -42,6 +46,10 @@ fn with_worktree_configs() -> git_testtools::Result {
         wt1_config.string("shared.setting").expect("exists").to_string(),
         "set in the shared config"
     );
+    assert_eq!(
+        wt1_config.string("override.setting").expect("exists").to_string(),
+        "set in the shared config"
+    );
 
     let wt2 = open(fixture_dir.join("wt-2")).unwrap();
     let wt2_config = wt2.config_snapshot();
@@ -63,6 +71,10 @@ fn with_worktree_configs() -> git_testtools::Result {
         wt2_config.string("shared.setting").expect("exists").to_string(),
         "set in the shared config"
     );
+    assert_eq!(
+        wt2_config.string("override.setting").expect("exists").to_string(),
+        "override in wt-2"
+    );
 
     Ok(())
 }

From a191948b758ab4e06a19eef748f16a5f458fe477 Mon Sep 17 00:00:00 2001
From: Sebastian Thiel <sebastian.thiel@icloud.com>
Date: Sat, 3 Dec 2022 20:00:19 +0100
Subject: [PATCH 11/14] Assure that worktree configuration is marked as such
 with `Source::Worktree`.

This also resets the original behaviour of reading `$COMMON_DIR/config`
as `Source::Local`.
---
 git-repository/src/config/cache/incubate.rs | 27 +++++++++++++++------
 1 file changed, 20 insertions(+), 7 deletions(-)

diff --git a/git-repository/src/config/cache/incubate.rs b/git-repository/src/config/cache/incubate.rs
index c516e5d3ec6..7861b643f2d 100644
--- a/git-repository/src/config/cache/incubate.rs
+++ b/git-repository/src/config/cache/incubate.rs
@@ -22,7 +22,13 @@ impl StageOne {
         lenient: bool,
     ) -> Result<Self, Error> {
         let mut buf = Vec::with_capacity(512);
-        let config = load_config(&mut buf, common_dir.join("config"), git_dir_trust, lossy)?;
+        let mut config = load_config(
+            common_dir.join("config"),
+            &mut buf,
+            git_config::Source::Local,
+            git_dir_trust,
+            lossy,
+        )?;
 
         let is_bare = util::config_bool(&config, "core.bare", false, lenient)?;
         let repo_format_version = config
@@ -45,10 +51,15 @@ impl StageOne {
             .unwrap_or(git_hash::Kind::Sha1);
 
         let extension_worktree = util::config_bool(&config, "extensions.worktreeConfig", false, lenient)?;
-        let config = if extension_worktree {
-            load_config(&mut buf, git_dir.join("config.worktree"), git_dir_trust, lossy)?
-        } else {
-            config
+        if extension_worktree {
+            let worktree_config = load_config(
+                git_dir.join("config.worktree"),
+                &mut buf,
+                git_config::Source::Worktree,
+                git_dir_trust,
+                lossy,
+            )?;
+            config.append(worktree_config);
         };
 
         let reflog = util::query_refupdates(&config, lenient)?;
@@ -64,16 +75,18 @@ impl StageOne {
 }
 
 fn load_config(
-    buf: &mut Vec<u8>,
     config_path: std::path::PathBuf,
+    buf: &mut Vec<u8>,
+    source: git_config::Source,
     git_dir_trust: git_sec::Trust,
     lossy: Option<bool>,
 ) -> Result<git_config::File<'static>, Error> {
+    buf.clear();
     std::io::copy(&mut std::fs::File::open(&config_path)?, buf)?;
 
     let config = git_config::File::from_bytes_owned(
         buf,
-        git_config::file::Metadata::from(git_config::Source::Worktree)
+        git_config::file::Metadata::from(source)
             .at(config_path)
             .with(git_dir_trust),
         git_config::file::init::Options {

From 75488a7d91abb90337d42f04e86e3d1373b8c19e Mon Sep 17 00:00:00 2001
From: Sebastian Thiel <sebastian.thiel@icloud.com>
Date: Sat, 3 Dec 2022 20:25:26 +0100
Subject: [PATCH 12/14] improve documentation about the configuration we always
 load

---
 git-repository/src/repository/permissions.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/git-repository/src/repository/permissions.rs b/git-repository/src/repository/permissions.rs
index 970add1058c..b1d51364c46 100644
--- a/git-repository/src/repository/permissions.rs
+++ b/git-repository/src/repository/permissions.rs
@@ -9,7 +9,9 @@ pub struct Permissions {
     pub config: Config,
 }
 
-/// Configure security relevant options when loading a git configuration.
+/// Configure from which sources git configuration may be loaded.
+///
+/// Note that configuration from inside of the repository is always loaded as it's definitely required for correctness.
 #[derive(Copy, Clone, Ord, PartialOrd, PartialEq, Eq, Debug, Hash)]
 pub struct Config {
     /// The git binary may come with configuration as part of its configuration, and if this is true (default false)

From 62afb7ba87311c5b04c8cd8002308d1b44959131 Mon Sep 17 00:00:00 2001
From: Sebastian Thiel <sebastian.thiel@icloud.com>
Date: Sat, 3 Dec 2022 20:27:39 +0100
Subject: [PATCH 13/14] move tests::repository::config::worktree to
 `tests::repository::open::worktree`

As these settings are relevant during opening and aren't queried later
as part of implementations in `repository::config` or `config`.
---
 git-repository/tests/repository/config/mod.rs |  1 -
 .../tests/repository/config/worktree.rs       | 80 ------------------
 git-repository/tests/repository/open.rs       | 83 +++++++++++++++++++
 3 files changed, 83 insertions(+), 81 deletions(-)
 delete mode 100644 git-repository/tests/repository/config/worktree.rs

diff --git a/git-repository/tests/repository/config/mod.rs b/git-repository/tests/repository/config/mod.rs
index 5465c7fa2fd..5b82895d3af 100644
--- a/git-repository/tests/repository/config/mod.rs
+++ b/git-repository/tests/repository/config/mod.rs
@@ -3,4 +3,3 @@ mod identity;
 mod remote;
 #[cfg(any(feature = "blocking-network-client", feature = "async-network-client"))]
 mod transport_options;
-mod worktree;
diff --git a/git-repository/tests/repository/config/worktree.rs b/git-repository/tests/repository/config/worktree.rs
deleted file mode 100644
index af047b0e810..00000000000
--- a/git-repository/tests/repository/config/worktree.rs
+++ /dev/null
@@ -1,80 +0,0 @@
-use git_repository::open;
-
-#[test]
-fn with_worktree_configs() -> git_testtools::Result {
-    let manifest_dir = std::path::PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
-
-    let fixture_dir = git_testtools::scripted_fixture_repo_read_only("make_worktree_repo_with_configs.sh").unwrap();
-
-    let base = open(fixture_dir.join("repo")).unwrap();
-    let base_config = base.config_snapshot();
-
-    assert_eq!(base.work_dir(), Some(fixture_dir.join("repo").as_path()));
-    assert_eq!(base.git_dir(), fixture_dir.join("repo/.git"));
-    assert_eq!(base.common_dir(), fixture_dir.join("repo/.git"));
-
-    assert_eq!(
-        base_config.string("worktree.setting").expect("exists").to_string(),
-        "set in the main worktree"
-    );
-    assert_eq!(
-        base_config.string("shared.setting").expect("exists").to_string(),
-        "set in the shared config"
-    );
-    assert_eq!(
-        base_config.string("override.setting").expect("exists").to_string(),
-        "set in the shared config"
-    );
-
-    let wt1 = open(fixture_dir.join("wt-1")).unwrap();
-    let wt1_config = wt1.config_snapshot();
-    assert_eq!(wt1.work_dir(), Some(fixture_dir.join("wt-1").as_path()));
-    assert_eq!(
-        wt1.git_dir(),
-        manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-1")
-    );
-    assert_eq!(
-        wt1.common_dir(),
-        manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-1/../..")
-    );
-
-    assert_eq!(
-        wt1_config.string("worktree.setting").expect("exists").to_string(),
-        "set in wt-1"
-    );
-    assert_eq!(
-        wt1_config.string("shared.setting").expect("exists").to_string(),
-        "set in the shared config"
-    );
-    assert_eq!(
-        wt1_config.string("override.setting").expect("exists").to_string(),
-        "set in the shared config"
-    );
-
-    let wt2 = open(fixture_dir.join("wt-2")).unwrap();
-    let wt2_config = wt2.config_snapshot();
-    assert_eq!(wt2.work_dir(), Some(fixture_dir.join("wt-2").as_path()));
-    assert_eq!(
-        wt2.git_dir(),
-        manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-2")
-    );
-    assert_eq!(
-        wt2.common_dir(),
-        manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-2/../..")
-    );
-
-    assert_eq!(
-        wt2_config.string("worktree.setting").expect("exists").to_string(),
-        "set in wt-2"
-    );
-    assert_eq!(
-        wt2_config.string("shared.setting").expect("exists").to_string(),
-        "set in the shared config"
-    );
-    assert_eq!(
-        wt2_config.string("override.setting").expect("exists").to_string(),
-        "override in wt-2"
-    );
-
-    Ok(())
-}
diff --git a/git-repository/tests/repository/open.rs b/git-repository/tests/repository/open.rs
index a0fdc013027..5cbd24e8007 100644
--- a/git-repository/tests/repository/open.rs
+++ b/git-repository/tests/repository/open.rs
@@ -225,3 +225,86 @@ mod with_overrides {
         Cow::Borrowed(s.into())
     }
 }
+
+mod worktree {
+    use git_repository::open;
+
+    #[test]
+    fn with_worktree_configs() -> git_testtools::Result {
+        let manifest_dir = std::path::PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
+
+        let fixture_dir = git_testtools::scripted_fixture_repo_read_only("make_worktree_repo_with_configs.sh").unwrap();
+
+        let base = open(fixture_dir.join("repo")).unwrap();
+        let base_config = base.config_snapshot();
+
+        assert_eq!(base.work_dir(), Some(fixture_dir.join("repo").as_path()));
+        assert_eq!(base.git_dir(), fixture_dir.join("repo/.git"));
+        assert_eq!(base.common_dir(), fixture_dir.join("repo/.git"));
+
+        assert_eq!(
+            base_config.string("worktree.setting").expect("exists").to_string(),
+            "set in the main worktree"
+        );
+        assert_eq!(
+            base_config.string("shared.setting").expect("exists").to_string(),
+            "set in the shared config"
+        );
+        assert_eq!(
+            base_config.string("override.setting").expect("exists").to_string(),
+            "set in the shared config"
+        );
+
+        let wt1 = open(fixture_dir.join("wt-1")).unwrap();
+        let wt1_config = wt1.config_snapshot();
+        assert_eq!(wt1.work_dir(), Some(fixture_dir.join("wt-1").as_path()));
+        assert_eq!(
+            wt1.git_dir(),
+            manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-1")
+        );
+        assert_eq!(
+            wt1.common_dir(),
+            manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-1/../..")
+        );
+
+        assert_eq!(
+            wt1_config.string("worktree.setting").expect("exists").to_string(),
+            "set in wt-1"
+        );
+        assert_eq!(
+            wt1_config.string("shared.setting").expect("exists").to_string(),
+            "set in the shared config"
+        );
+        assert_eq!(
+            wt1_config.string("override.setting").expect("exists").to_string(),
+            "set in the shared config"
+        );
+
+        let wt2 = open(fixture_dir.join("wt-2")).unwrap();
+        let wt2_config = wt2.config_snapshot();
+        assert_eq!(wt2.work_dir(), Some(fixture_dir.join("wt-2").as_path()));
+        assert_eq!(
+            wt2.git_dir(),
+            manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-2")
+        );
+        assert_eq!(
+            wt2.common_dir(),
+            manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-2/../..")
+        );
+
+        assert_eq!(
+            wt2_config.string("worktree.setting").expect("exists").to_string(),
+            "set in wt-2"
+        );
+        assert_eq!(
+            wt2_config.string("shared.setting").expect("exists").to_string(),
+            "set in the shared config"
+        );
+        assert_eq!(
+            wt2_config.string("override.setting").expect("exists").to_string(),
+            "override in wt-2"
+        );
+
+        Ok(())
+    }
+}

From 2d83222dbf607f78acad4874580d1f007d838c13 Mon Sep 17 00:00:00 2001
From: Sebastian Thiel <sebastian.thiel@icloud.com>
Date: Sat, 3 Dec 2022 20:51:47 +0100
Subject: [PATCH 14/14] refactor

This is just to keep in-code notes in the form of assertion messages,
after validating each assertion one by one and forcing myself
to understand them.
---
 git-repository/tests/repository/open.rs | 150 +++++++++++++-----------
 1 file changed, 84 insertions(+), 66 deletions(-)

diff --git a/git-repository/tests/repository/open.rs b/git-repository/tests/repository/open.rs
index 5cbd24e8007..3768f74c5e3 100644
--- a/git-repository/tests/repository/open.rs
+++ b/git-repository/tests/repository/open.rs
@@ -231,79 +231,97 @@ mod worktree {
 
     #[test]
     fn with_worktree_configs() -> git_testtools::Result {
-        let manifest_dir = std::path::PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
+        let manifest_dir = std::path::PathBuf::from(std::env::var("CARGO_MANIFEST_DIR")?);
+        let fixture_dir = git_testtools::scripted_fixture_repo_read_only("make_worktree_repo_with_configs.sh")?;
+        let worktree_base = manifest_dir.join(&fixture_dir).join("repo/.git/worktrees");
 
-        let fixture_dir = git_testtools::scripted_fixture_repo_read_only("make_worktree_repo_with_configs.sh").unwrap();
+        {
+            let base = open(fixture_dir.join("repo"))?;
+            let base_config = base.config_snapshot();
 
-        let base = open(fixture_dir.join("repo")).unwrap();
-        let base_config = base.config_snapshot();
-
-        assert_eq!(base.work_dir(), Some(fixture_dir.join("repo").as_path()));
-        assert_eq!(base.git_dir(), fixture_dir.join("repo/.git"));
-        assert_eq!(base.common_dir(), fixture_dir.join("repo/.git"));
+            assert_eq!(
+                base.work_dir(),
+                Some(fixture_dir.join("repo").as_path()),
+                "the main worktree"
+            );
+            assert_eq!(base.git_dir(), fixture_dir.join("repo/.git"), "git dir and…");
+            assert_eq!(
+                base.common_dir(),
+                fixture_dir.join("repo/.git"),
+                "…common dir are the same"
+            );
 
-        assert_eq!(
-            base_config.string("worktree.setting").expect("exists").to_string(),
-            "set in the main worktree"
-        );
-        assert_eq!(
-            base_config.string("shared.setting").expect("exists").to_string(),
-            "set in the shared config"
-        );
-        assert_eq!(
-            base_config.string("override.setting").expect("exists").to_string(),
-            "set in the shared config"
-        );
+            assert_eq!(
+                base_config.string("worktree.setting").expect("exists").as_ref(),
+                "set in the main worktree"
+            );
+            assert_eq!(
+                base_config.string("shared.setting").expect("exists").as_ref(),
+                "set in the shared config"
+            );
+            assert_eq!(
+                base_config.string("override.setting").expect("exists").as_ref(),
+                "set in the shared config"
+            );
+        }
 
-        let wt1 = open(fixture_dir.join("wt-1")).unwrap();
-        let wt1_config = wt1.config_snapshot();
-        assert_eq!(wt1.work_dir(), Some(fixture_dir.join("wt-1").as_path()));
-        assert_eq!(
-            wt1.git_dir(),
-            manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-1")
-        );
-        assert_eq!(
-            wt1.common_dir(),
-            manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-1/../..")
-        );
+        {
+            let wt1 = open(fixture_dir.join("wt-1"))?;
+            let wt1_config = wt1.config_snapshot();
+            assert_eq!(
+                wt1.work_dir(),
+                Some(fixture_dir.join("wt-1").as_path()),
+                "a linked worktree in its own location"
+            );
+            assert_eq!(
+                wt1.git_dir(),
+                worktree_base.join("wt-1"),
+                "whose git-dir is within the common dir"
+            );
+            assert_eq!(
+                wt1.common_dir(),
+                worktree_base.join("wt-1/../.."),
+                "the common dir is the `git-dir` of the repository with the main worktree"
+            );
 
-        assert_eq!(
-            wt1_config.string("worktree.setting").expect("exists").to_string(),
-            "set in wt-1"
-        );
-        assert_eq!(
-            wt1_config.string("shared.setting").expect("exists").to_string(),
-            "set in the shared config"
-        );
-        assert_eq!(
-            wt1_config.string("override.setting").expect("exists").to_string(),
-            "set in the shared config"
-        );
+            assert_eq!(
+                wt1_config.string("worktree.setting").expect("exists").as_ref(),
+                "set in wt-1"
+            );
+            assert_eq!(
+                wt1_config.string("shared.setting").expect("exists").as_ref(),
+                "set in the shared config"
+            );
+            assert_eq!(
+                wt1_config.string("override.setting").expect("exists").as_ref(),
+                "set in the shared config"
+            );
+        }
 
-        let wt2 = open(fixture_dir.join("wt-2")).unwrap();
-        let wt2_config = wt2.config_snapshot();
-        assert_eq!(wt2.work_dir(), Some(fixture_dir.join("wt-2").as_path()));
-        assert_eq!(
-            wt2.git_dir(),
-            manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-2")
-        );
-        assert_eq!(
-            wt2.common_dir(),
-            manifest_dir.join(&fixture_dir).join("repo/.git/worktrees/wt-2/../..")
-        );
+        {
+            let wt2 = open(fixture_dir.join("wt-2"))?;
+            let wt2_config = wt2.config_snapshot();
+            assert_eq!(
+                wt2.work_dir(),
+                Some(fixture_dir.join("wt-2").as_path()),
+                "another linked worktree as sibling to wt-1"
+            );
+            assert_eq!(wt2.git_dir(), worktree_base.join("wt-2"));
+            assert_eq!(wt2.common_dir(), worktree_base.join("wt-2/../.."));
 
-        assert_eq!(
-            wt2_config.string("worktree.setting").expect("exists").to_string(),
-            "set in wt-2"
-        );
-        assert_eq!(
-            wt2_config.string("shared.setting").expect("exists").to_string(),
-            "set in the shared config"
-        );
-        assert_eq!(
-            wt2_config.string("override.setting").expect("exists").to_string(),
-            "override in wt-2"
-        );
+            assert_eq!(
+                wt2_config.string("worktree.setting").expect("exists").as_ref(),
+                "set in wt-2"
+            );
+            assert_eq!(
+                wt2_config.string("shared.setting").expect("exists").as_ref(),
+                "set in the shared config"
+            );
+            assert_eq!(
+                wt2_config.string("override.setting").expect("exists").as_ref(),
+                "override in wt-2"
+            );
+        }
 
         Ok(())
     }