support detached head, symlinks, executable bit; annotate optional code

add

@@ -7,18 +7,18 @@ import sys
 
 import index
 
-filenames = subprocess.check_output(['find'] + sys.argv[1:] + ['!', '-type', 'd']).splitlines()
+filenames = subprocess.check_output(['find'] + sys.argv[1:] + ['!', '-type', 'd']).splitlines() # for directories
 entries = index.read_index()
 for filename in filenames:
     entries = [e for e in entries if e[0] != filename]
     if os.path.exists(filename):
-        if os.path.islink(filename):
+        if os.path.islink(filename): # for symlinks
             mode = 0120000
             with open('.zit/blob.tmp', 'w') as f:
                 f.write(os.readlink(filename))
             sha1 = subprocess.check_output(['hash-object', 'blob', '.zit/blob.tmp']).strip()
         else:
-            if os.access(filename, os.X_OK):
+            if os.access(filename, os.X_OK): # for executable files
                 mode = 0100755
             else:
                 mode = 0100644

branch

@@ -1,7 +1,7 @@
 #!/bin/bash -e
 
 if [[ $# -eq 0 ]]; then
-    headref=$(symbolic-ref HEAD | sed -e 's|^refs/heads/||')
+    headref=$(symbolic-ref HEAD | sed -e 's|^refs/heads/||') # for current branch
     echo "*$headref"
     cd .zit/refs/heads
     ls | grep -vxF $headref

checkout

@@ -11,5 +11,7 @@ checkout-index
 if [[ -f .zit/refs/heads/$revision ]]; then
     symbolic-ref HEAD refs/heads/$revision
 else
+    rev-parse $revision > .zit/HEAD.tmp
+    mv .zit/HEAD.tmp .zit/HEAD
     echo "You are in 'detached HEAD' state." >&2
 fi

checkout-index

@@ -13,8 +13,10 @@ for filename, mode, sha1 in entries:
     subprocess.check_call(['mkdir', '-p', './' + os.path.dirname(filename)])
     # TODO git 1.0 doesn't seem to unlink deleted files
     subprocess.check_call(['cat-file', 'blob', sha1.encode('hex')], stdout=open(filename, 'w'))
-    if mode == 0100755:
+    if mode == 0100755: # for executable files
         os.chmod(filename, 0755)
-    elif mode == 0120000:
+    elif mode == 0120000: # for symlinks
         target = open(filename).read()
+        if os.path.exists(filename):
+            os.unlink(filename)
         os.symlink(target, filename)

commit

@@ -1,6 +1,6 @@
 #!/bin/bash -e
 
-if [[ -f .zit/$(symbolic-ref HEAD) ]]; then
+if [[ -f .zit/$(symbolic-ref HEAD) ]]; then # for non-initial commit
     parents='-p HEAD'
 fi
 echo '# write a commit message' > .zit/COMMIT_EDITMSG

commit-tree

@@ -1,13 +1,14 @@
 #!/bin/bash -e
 
+# for non-hardcoded commit
 export ZIT_AUTHOR_NAME="${ZIT_AUTHOR_NAME-Frank N. Stein}"
 export ZIT_AUTHOR_EMAIL="${ZIT_AUTHOR_EMAIL-eat@brains.com}"
 export ZIT_COMMITTER_NAME="${ZIT_COMMITTER_NAME-$ZIT_AUTHOR_NAME}"
 export ZIT_COMMITTER_EMAIL="${ZIT_COMMITTER_EMAIL-$ZIT_AUTHOR_EMAIL}"
 
 echo tree $1 > .zit/commit.tmp
 shift
-while [[ $1 == -p ]]; do
+while [[ $1 == -p ]]; do # for non-initial commit
     parent=$(rev-parse $2)
     echo parent $parent >> .zit/commit.tmp
     shift; shift

init

@@ -3,6 +3,7 @@
 mkdir -p "$1/.zit/objects"
 echo 'ref: refs/heads/master' > "$1/.zit/HEAD"
 
+# for git compatibility
 ln -s .zit "$1/.git"
 mkdir "$1/.git/info"
 echo .zit > "$1/.git/info/exclude"

rev-parse

@@ -6,15 +6,15 @@ import sys
 
 # sha1_name.c:get_sha1
 def get_sha1(name):
-    if name[-2] == '~':
+    if name[-2] == '~': # for ~
         name = name[:-2] + '^' * int(name[-1])
-    if name[-1] == '^':
+    if name[-1] == '^': # for ^
         sha1 = get_sha1(name[:-1])
         contents = subprocess.check_output(['cat-file', 'commit', sha1])
         parent = next(line for line in contents.splitlines()
                       if line.startswith('parent '))
         return parent.split(' ')[1]
-    if '^{' in name:
+    if '^{' in name: # for ^{type}
         name, requested_type = name.rsplit('^{', 1)
         assert requested_type[-1] == '}'
         requested_type = requested_type[:-1]

test

@@ -13,101 +13,124 @@ get_md5() {
 }
 
 header 'Initializing repo... [zit, init]'
+[[ $1 == --keep ]] && { keep=1; shift; }
+ZIT="${1-zit}"
 trap 'echo -e "\e[31mFAIL\e[0m"' ERR
 repo="$PWD/test.tmp"
 rm -rf "$repo"
-zit init "$repo"
-[[ $1 != --keep ]] && trap 'rm -rf "$repo"' EXIT
+$ZIT init "$repo"
+[[ -n $keep ]] || trap 'rm -rf "$repo"' EXIT
 cd "$repo"
 [[ $(<.zit/HEAD) == 'ref: refs/heads/master' ]]
+[[ ${ZIT::1} == / ]] || ZIT="../$ZIT"
 
 header 'Writing a blob object... [hash-object]'
 echo "I'm a little teapot" > lullaby
-[[ $(zit hash-object blob lullaby) == 3eb7f9afc452afe452b99d478d89264380622248 ]]
+[[ $($ZIT hash-object blob lullaby) == 3eb7f9afc452afe452b99d478d89264380622248 ]]
 
 header 'Reading an object... [cat-file]'
-[[ $(zit cat-file -t 3eb7f9afc452afe452b99d478d89264380622248 ) == blob ]]
-[[ $(zit cat-file blob 3eb7f9afc452afe452b99d478d89264380622248 ) == "I'm a little teapot" ]]
+[[ $($ZIT cat-file -t 3eb7f9afc452afe452b99d478d89264380622248 ) == blob ]]
+[[ $($ZIT cat-file blob 3eb7f9afc452afe452b99d478d89264380622248 ) == "I'm a little teapot" ]]
 
 header 'Writing to the index... [index.py]'
-PYTHONPATH=.. /usr/bin/python -c 'import index; index.write_index([("lullaby", 0100644, "\x3e\xb7\xf9\xaf\xc4\x52\xaf\xe4\x52\xb9\x9d\x47\x8d\x89\x26\x43\x80\x62\x22\x48")])'
+PYTHONPATH=$(dirname "$ZIT") /usr/bin/python -c 'import index; index.write_index([("lullaby", 0100644, "\x3e\xb7\xf9\xaf\xc4\x52\xaf\xe4\x52\xb9\x9d\x47\x8d\x89\x26\x43\x80\x62\x22\x48")])'
 [[ $(get_md5 .zit/index) == 06432001fc95f78cd6353321f7c95009 ]]
 
 header 'Adding a file to the index... [add]'
 echo here > handle
-zit add handle
-[[ $(zit cat-file blob 012ea92e81171f5ef7486696878656c5263cf722 ) == here ]]
+$ZIT add handle
+[[ $($ZIT cat-file blob 012ea92e81171f5ef7486696878656c5263cf722 ) == here ]]
 [[ $(get_md5 .zit/index) == 61728e18ee75d24576d9ea2b626fb1ff ]]
 
 header 'Reading the index... [index.py]'
-[[ $(PYTHONPATH=.. /usr/bin/python -c 'import index; print index.read_index()') == "[('handle', 33188, '\x01.\xa9.\x81\x17\x1f^\xf7Hf\x96\x87\x86V\xc5&<\xf7\"'), ('lullaby', 33188, '>\xb7\xf9\xaf\xc4R\xaf\xe4R\xb9\x9dG\x8d\x89&C\x80b\"H')]" ]]
+[[ $(PYTHONPATH=$(dirname "$ZIT") /usr/bin/python -c 'import index; print index.read_index()') == "[('handle', 33188, '\x01.\xa9.\x81\x17\x1f^\xf7Hf\x96\x87\x86V\xc5&<\xf7\"'), ('lullaby', 33188, '>\xb7\xf9\xaf\xc4R\xaf\xe4R\xb9\x9dG\x8d\x89&C\x80b\"H')]" ]]
 
 header 'Writing the index to a tree object... [write-tree]'
-initial_tree=$(zit write-tree)
+initial_tree=$($ZIT write-tree)
 [[ $initial_tree == f65ccd4f10cb3416c7be6601bafd2371a784054f ]]
 
 header 'Writing an initial commit object... [commit-tree]'
-export ZIT_AUTHOR_NAME='Miss Teapot' [email protected]
-initial_commit=$(echo initial commit | zit commit-tree $initial_tree)
-[[ $(zit cat-file commit $initial_commit ) =~ ^"tree $initial_tree
-author Miss Teapot <[email protected]> "[0-9]*\ [+-][0-9]{4}"
-committer Miss Teapot <[email protected]> "[0-9]*\ [+-][0-9]{4}"
+initial_commit=$(echo initial commit | $ZIT commit-tree $initial_tree)
+[[ $($ZIT cat-file commit $initial_commit ) =~ ^"tree $initial_tree
+author "[^\<]*" <"[^\>]*"> "[0-9]*\ [+-][0-9]{4}"
+committer "[^\<]*" <"[^\>]*"> "[0-9]*\ [+-][0-9]{4}"
 
 initial commit"$ ]]
 
 header 'Create a branch ref [update-ref]'
-zit update-ref refs/heads/initial $initial_commit
+$ZIT update-ref refs/heads/initial $initial_commit
 [[ $(<.zit/refs/heads/initial) == $initial_commit ]]
 
 header 'Read HEAD symbolic ref [symbolic-ref]'
-[[ $(zit symbolic-ref HEAD) == refs/heads/master ]]
+[[ $($ZIT symbolic-ref HEAD) == refs/heads/master ]]
 
 header 'Birth master branch [update-ref, get-sha1-basic, rev-parse]'
-zit update-ref HEAD $initial_commit
-[[ $(zit rev-parse HEAD) == $initial_commit ]]
+$ZIT update-ref HEAD $initial_commit
+[[ $($ZIT rev-parse HEAD) == $initial_commit ]]
 
 header 'Delete and create a branch [branch]'
-zit branch -d initial
+$ZIT branch -d initial
 [[ ! -f .zit/refs/heads/initial ]]
-zit branch initial
+$ZIT branch initial
 [[ $(<.zit/refs/heads/initial) == $initial_commit ]]
 
 header 'Writing another commit object... [commit, commit-tree]'
 echo 'short and stout' > lullaby
-zit add lullaby
-echo 'second verse' | EDITOR=tee zit commit > /dev/null
+$ZIT add lullaby
+EDITOR=tee $ZIT commit <<< 'second verse' > /dev/null
 second_tree=3c1bea2d45d260a3836794e04a4bbef34e3c2459
-[[ $(zit cat-file commit $(zit rev-parse HEAD) ) =~ ^"tree $second_tree
+second_commit=$($ZIT rev-parse HEAD)
+[[ $($ZIT cat-file commit $second_commit ) =~ ^"tree $second_tree
 parent $initial_commit
-author Miss Teapot <[email protected]> "[0-9]*\ [+-][0-9]{4}"
-committer Miss Teapot <[email protected]> "[0-9]*\ [+-][0-9]{4}"
+author "[^\<]*" <"[^\>]*"> "[0-9]*\ [+-][0-9]{4}"
+committer "[^\<]*" <"[^\>]*"> "[0-9]*\ [+-][0-9]{4}"
 
 second verse"$ ]]
 
 header 'Parse ^ and ~ revisions [rev-parse]'
-[[ $(zit rev-parse HEAD^) == $initial_commit ]]
-[[ $(zit rev-parse HEAD~1) == $initial_commit ]]
-[[ $(zit rev-parse initial~0) == $initial_commit ]]
+[[ $($ZIT rev-parse HEAD^) == $initial_commit ]]
+[[ $($ZIT rev-parse HEAD~1) == $initial_commit ]]
+[[ $($ZIT rev-parse initial~0) == $initial_commit ]]
 
 header 'Parse ^{type} revisions [rev-parse]'
-[[ $(zit rev-parse HEAD^{tree}) == $second_tree ]]
-[[ $(zit rev-parse HEAD^^{tree}) == $initial_tree ]]
+[[ $($ZIT rev-parse HEAD^{tree}) == $second_tree ]]
+[[ $($ZIT rev-parse HEAD^^{tree}) == $initial_tree ]]
 
 header 'Reading tree object into the index... [read-tree]'
-zit read-tree $initial_tree
+$ZIT read-tree $initial_tree
 [[ $(get_md5 .zit/index) == 61728e18ee75d24576d9ea2b626fb1ff ]]
 
 header 'Checkout from the index [checkout-index]'
-zit checkout-index
+$ZIT checkout-index
 [[ $(<lullaby) == "I'm a little teapot" ]]
 
 header 'Update HEAD symbolic ref [symbolic-ref]'
-zit symbolic-ref HEAD refs/heads/initial
+$ZIT symbolic-ref HEAD refs/heads/initial
 [[ $(<.zit/HEAD) == 'ref: refs/heads/initial' ]]
 
 header 'Checkout master branch [checkout]'
-zit checkout master
+$ZIT checkout master
 [[ $(<lullaby) == 'short and stout' ]]
 [[ $(<.zit/HEAD) == 'ref: refs/heads/master' ]]
 
+header 'Checkout detached HEAD [checkout]'
+$ZIT checkout HEAD
+[[ $(<.zit/HEAD) == $second_commit ]]
+
+header 'Commit executable file, symlink, and directory [add]'
+chmod +x handle
+mkdir and
+ln -s ../handle and/spout
+git add handle and/spout
+EDITOR=tee $ZIT commit <<< 'first stanza' > /dev/null
+[[ $($ZIT rev-parse HEAD^{tree}) == 6a8ad12fa34d4f1ea64abb28c8ae143b1e8fde40 ]]
+
+header 'Checkout a new branch [checkout, checkout-index]'
+rm -rf handle and
+$ZIT checkout -b stanza
+[[ $(<.zit/HEAD) == 'ref: refs/heads/stanza' ]]
+[[ -x handle ]]
+[[ $(python -c 'import os; print os.readlink("and/spout")') == ../handle ]]
+
+[[ -n $keep ]] || { rm -rf "$repo"; trap '' EXIT; }
 header PASS