Clean up work-tree handling

The old version of work-tree support was an unholy mess, barely readable,
and not to the point.

For example, why do you have to provide a worktree, when it is not used?
As in "git status".  Now it works.

Another riddle was: if you can have work trees inside the git dir, why
are some programs complaining that they need a work tree?

IOW it is allowed to call

	$ git --git-dir=../ --work-tree=. bla

when you really want to.  In this case, you are both in the git directory
and in the working tree.  So, programs have to actually test for the right
thing, namely if they are inside a working tree, and not if they are
inside a git directory.

Also, GIT_DIR=../.git should behave the same as if no GIT_DIR was
specified, unless there is a repository in the current working directory.
It does now.

The logic to determine if a repository is bare, or has a work tree
(tertium non datur), is this:

--work-tree=bla overrides GIT_WORK_TREE, which overrides core.bare = true,
which overrides core.worktree, which overrides GIT_DIR/.. when GIT_DIR
ends in /.git, which overrides the directory in which .git/ was found.

In related news, a long standing bug was fixed: when in .git/bla/x.git/,
which is a bare repository, git formerly assumed ../.. to be the
appropriate git dir.  This problem was reported by Shawn Pearce to have
caused much pain, where a colleague mistakenly ran "git init" in "/" a
long time ago, and bare repositories just would not work.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

2 files changed, 29 insertions, 15 deletions

diff --git a/t/t1500-rev-parse.sh b/t/t1500-rev-parse.sh
index ec4996637..bea40cba8 100755
--- a/t/t1500-rev-parse.sh
+++ b/t/t1500-rev-parse.sh
@@ -31,9 +31,9 @@ test_rev_parse() {
 test_rev_parse toplevel false false true ''
 
 cd .git || exit 1
-test_rev_parse .git/ false true true .git/
+test_rev_parse .git/ true true false ''
 cd objects || exit 1
-test_rev_parse .git/objects/ false true true .git/objects/
+test_rev_parse .git/objects/ true true false ''
 cd ../.. || exit 1
 
 mkdir -p sub/dir || exit 1
@@ -42,7 +42,7 @@ test_rev_parse subdirectory false false true sub/dir/
 cd ../.. || exit 1
 
 git config core.bare true
-test_rev_parse 'core.bare = true' true false true
+test_rev_parse 'core.bare = true' true false false
 
 git config --unset core.bare
 test_rev_parse 'core.bare undefined' false false true
@@ -50,28 +50,28 @@ test_rev_parse 'core.bare undefined' false false true
 mkdir work || exit 1
 cd work || exit 1
 export GIT_DIR=../.git
-export GIT_CONFIG="$GIT_DIR"/config
+export GIT_CONFIG="$(pwd)"/../.git/config
 
 git config core.bare false
-test_rev_parse 'GIT_DIR=../.git, core.bare = false' false false true ''
+test_rev_parse 'GIT_DIR=../.git, core.bare = false' false false true work/
 
 git config core.bare true
-test_rev_parse 'GIT_DIR=../.git, core.bare = true' true false true ''
+test_rev_parse 'GIT_DIR=../.git, core.bare = true' true false false ''
 
 git config --unset core.bare
-test_rev_parse 'GIT_DIR=../.git, core.bare undefined' false false true ''
+test_rev_parse 'GIT_DIR=../.git, core.bare undefined' false false true work/
 
 mv ../.git ../repo.git || exit 1
 export GIT_DIR=../repo.git
-export GIT_CONFIG="$GIT_DIR"/config
+export GIT_CONFIG="$(pwd)"/../repo.git/config
 
 git config core.bare false
 test_rev_parse 'GIT_DIR=../repo.git, core.bare = false' false false true ''
 
 git config core.bare true
-test_rev_parse 'GIT_DIR=../repo.git, core.bare = true' true false true ''
+test_rev_parse 'GIT_DIR=../repo.git, core.bare = true' true false false ''
 
 git config --unset core.bare
-test_rev_parse 'GIT_DIR=../repo.git, core.bare undefined' true false true ''
+test_rev_parse 'GIT_DIR=../repo.git, core.bare undefined' false false true ''
 
 test_done
diff --git a/t/t1501-worktree.sh b/t/t1501-worktree.sh
index aadeeab9a..732216184 100755
--- a/t/t1501-worktree.sh
+++ b/t/t1501-worktree.sh
@@ -33,17 +33,17 @@ mv .git repo.git || exit 1
 
 say "core.worktree = relative path"
 export GIT_DIR=repo.git
-export GIT_CONFIG=$GIT_DIR/config
+export GIT_CONFIG="$(pwd)"/$GIT_DIR/config
 unset GIT_WORK_TREE
 git config core.worktree ../work
 test_rev_parse 'outside'      false false false
 cd work || exit 1
 export GIT_DIR=../repo.git
-export GIT_CONFIG=$GIT_DIR/config
+export GIT_CONFIG="$(pwd)"/$GIT_DIR/config
 test_rev_parse 'inside'       false false true ''
 cd sub/dir || exit 1
 export GIT_DIR=../../../repo.git
-export GIT_CONFIG=$GIT_DIR/config
+export GIT_CONFIG="$(pwd)"/$GIT_DIR/config
 test_rev_parse 'subdirectory' false false true sub/dir/
 cd ../../.. || exit 1
 
@@ -84,9 +84,23 @@ test_rev_parse 'in repo.git'              false true  false
 cd objects || exit 1
 test_rev_parse 'in repo.git/objects'      false true  false
 cd ../work || exit 1
-test_rev_parse 'in repo.git/work'         false false true ''
+test_rev_parse 'in repo.git/work'         false true true ''
 cd sub/dir || exit 1
-test_rev_parse 'in repo.git/sub/dir' false false true sub/dir/
+test_rev_parse 'in repo.git/sub/dir' false true true sub/dir/
 cd ../../../.. || exit 1
 
+test_expect_success 'repo finds its work tree' '
+	(cd repo.git &&
+	 : > work/sub/dir/untracked &&
+	 test sub/dir/untracked = "$(git ls-files --others)")
+'
+
+test_expect_success 'repo finds its work tree from work tree, too' '
+	(cd repo.git/work/sub/dir &&
+	 : > tracked &&
+	 git --git-dir=../../.. add tracked &&
+	 cd ../../.. &&
+	 test sub/dir/tracked = "$(git ls-files)")
+'
+
 test_done