e2e: Add caching to git repositories

It's very expensive to create new repositories from scratch. To avoid
this, a new repo & remotes are only created if necessary (depending on a
cache key given on request). If not created, they are simply copied from
a stored, clean repository / remote.

e2e_tests/test_worktrees.py

@@ -96,7 +96,7 @@ def test_worktree_add(
 
 
 def test_worktree_add_invalid_name():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         for worktree_name in ["/absolute/path" "trailingslash/"]:
             args = ["wt", "add", worktree_name]
             cmd = grm(args, cwd=base_dir)
@@ -127,7 +127,7 @@ def test_worktree_add_into_invalid_subdirectory():
 def test_worktree_add_with_tracking(
     remote_branch_already_exists, has_config, has_default, has_prefix
 ):
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         if has_config:
             with open(os.path.join(base_dir, "grm.toml"), "w") as f:
                 f.write(
@@ -229,7 +229,7 @@ def test_worktree_add_with_explicit_no_tracking(
 
 
 def test_worktree_delete():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test", "--track", "origin/test"], cwd=base_dir)
         assert cmd.returncode == 0
         assert "test" in os.listdir(base_dir)
@@ -246,7 +246,7 @@ def test_worktree_delete():
 
 
 def test_worktree_delete_refusal_no_tracking_branch():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test"], cwd=base_dir)
         assert cmd.returncode == 0
 
@@ -262,7 +262,7 @@ def test_worktree_delete_refusal_no_tracking_branch():
 
 
 def test_worktree_delete_refusal_uncommited_changes_new_file():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test", "--track", "origin/test"], cwd=base_dir)
         assert cmd.returncode == 0
 
@@ -280,7 +280,7 @@ def test_worktree_delete_refusal_uncommited_changes_new_file():
 
 
 def test_worktree_delete_refusal_uncommited_changes_changed_file():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test", "--track", "origin/test"], cwd=base_dir)
         assert cmd.returncode == 0
 
@@ -298,7 +298,7 @@ def test_worktree_delete_refusal_uncommited_changes_changed_file():
 
 
 def test_worktree_delete_refusal_uncommited_changes_deleted_file():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test", "--track", "origin/test"], cwd=base_dir)
         assert cmd.returncode == 0
 
@@ -318,7 +318,7 @@ def test_worktree_delete_refusal_uncommited_changes_deleted_file():
 
 
 def test_worktree_delete_refusal_commited_changes():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test", "--track", "origin/test"], cwd=base_dir)
         assert cmd.returncode == 0
 
@@ -338,7 +338,7 @@ def test_worktree_delete_refusal_commited_changes():
 
 
 def test_worktree_delete_refusal_tracking_branch_mismatch():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test", "--track", "origin/test"], cwd=base_dir)
         assert cmd.returncode == 0
 
@@ -358,7 +358,7 @@ def test_worktree_delete_refusal_tracking_branch_mismatch():
 
 
 def test_worktree_delete_force_refusal():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test"], cwd=base_dir)
         assert cmd.returncode == 0
 
@@ -368,7 +368,7 @@ def test_worktree_delete_force_refusal():
 
 
 def test_worktree_add_delete_add():
-    with TempGitRepositoryWorktree() as (base_dir, _commit):
+    with TempGitRepositoryWorktree.get(funcname()) as (base_dir, _commit):
         cmd = grm(["wt", "add", "test", "--track", "origin/test"], cwd=base_dir)
         assert cmd.returncode == 0
         assert "test" in os.listdir(base_dir)