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[PATCH 2/2] fast-import: tighten M 040000 syntax

From
Jonathan Nieder <jrnieder@gmail.com>
Date
Oct 18, 2010, 01:08 UTC
Message-ID
<20101018010853.GC25524@burratino>
In-Reply-To
<20101018010005.GA25524@burratino>

When tree_content_set() is asked to modify the path "foo/bar/", it first recurses like so:

	tree_content_set(root, "foo/bar/", sha1, S_IFDIR) ->
	 tree_content_set(root:foo, "bar/", ...) ->
	  tree_content_set(root:foo/bar, "", ...)

And as a side-effect of 2794ad5 (fast-import: Allow filemodify to set the root, 2010-10-10), this last call is accepted and changes the tree entry for root:foo/bar to refer to the specified tree.

That seems safe enough but let's reject the new syntax (we never meant to support it) and make it harder for frontends to introduce pointless incompatibilities with git fast-import 1.7.3.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
---
 fast-import.c          |   34 +++++++++++++++++++++++++---------
 t/t9300-fast-import.sh |   30 ++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+), 9 deletions(-)
diff --git a/fast-import.c b/fast-import.c
index aaf47c5..cb947c1 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -1437,6 +1437,20 @@ static void store_tree(struct tree_entry *root)
 	t->entry_count -= del;
 }
 
+static void tree_content_replace(
+	struct tree_entry *root,
+	const unsigned char *sha1,
+	const uint16_t mode,
+	struct tree_content *newtree)
+{
+	if (!S_ISDIR(mode))
+		die("Root cannot be a non-directory");
+	hashcpy(root->versions[1].sha1, sha1);
+	if (root->tree)
+		release_tree_content_recursive(root->tree);
+	root->tree = newtree;
+}
+
 static int tree_content_set(
 	struct tree_entry *root,
 	const char *p,
@@ -1454,15 +1468,6 @@ static int tree_content_set(
 		n = slash1 - p;
 	else
 		n = strlen(p);
-	if (!slash1 && !n) {
-		if (!S_ISDIR(mode))
-			die("Root cannot be a non-directory");
-		hashcpy(root->versions[1].sha1, sha1);
-		if (root->tree)
-			release_tree_content_recursive(root->tree);
-		root->tree = subtree;
-		return 1;
-	}
 	if (!n)
 		die("Empty path component found in input");
 	if (!slash1 && !S_ISDIR(mode) && subtree)
@@ -2230,6 +2235,10 @@ static void file_change_m(struct branch *b)
 				command_buf.buf);
 	}
 
+	if (!*p) {
+		tree_content_replace(&b->branch_tree, sha1, mode, NULL);
+		return;
+	}
 	tree_content_set(&b->branch_tree, p, sha1, mode, NULL);
 }
 
@@ -2288,6 +2297,13 @@ static void file_change_cr(struct branch *b, int rename)
 		tree_content_get(&b->branch_tree, s, &leaf);
 	if (!leaf.versions[1].mode)
 		die("Path %s not in branch", s);
+	if (!*d) {	/* C "path/to/subdir" "" */
+		tree_content_replace(&b->branch_tree,
+			leaf.versions[1].sha1,
+			leaf.versions[1].mode,
+			leaf.tree);
+		return;
+	}
 	tree_content_set(&b->branch_tree, d,
 		leaf.versions[1].sha1,
 		leaf.versions[1].mode,
diff --git a/t/t9300-fast-import.sh b/t/t9300-fast-import.sh
index 1df11ad..ce09457 100755
--- a/t/t9300-fast-import.sh
+++ b/t/t9300-fast-import.sh
@@ -929,6 +929,20 @@ test_expect_success \
 	 compare_diff_raw expect actual'
 
 test_expect_success \
+	'N: reject foo/ syntax' \
+	'subdir=$(git rev-parse refs/heads/branch^0:file2) &&
+	 test_must_fail git fast-import <<-INPUT_END
+	commit refs/heads/N5B
+	committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+	data <<COMMIT
+	copy with invalid syntax
+	COMMIT
+
+	from refs/heads/branch^0
+	M 040000 $subdir file3/
+	INPUT_END'
+
+test_expect_success \
 	'N: copy to root by id and modify' \
 	'echo "hello, world" >expect.foo &&
 	 echo hello >expect.bar &&
@@ -965,6 +979,22 @@ test_expect_success \
 	 test_cmp expect.foo actual.foo &&
 	 test_cmp expect.bar actual.bar'
 
+test_expect_success \
+	'N: extract subtree' \
+	'branch=$(git rev-parse --verify refs/heads/branch^{tree}) &&
+	 cat >input <<-INPUT_END &&
+	commit refs/heads/N9
+	committer $GIT_COMMITTER_NAME <$GIT_COMMITTER_EMAIL> $GIT_COMMITTER_DATE
+	data <<COMMIT
+	extract subtree branch:newdir
+	COMMIT
+
+	M 040000 $branch ""
+	R "newdir" ""
+	INPUT_END
+	 git fast-import <input &&
+	 git diff --exit-code branch:newdir N9'
+
 ###
 ### series O
 ###
-- 
1.7.2.3
Previous: Jonathan NiederNext: Jonathan Nieder
Message 26 of 31 in “fast-import: Allow filemodify to set the root”
  1. fast-import: Allow filemodify to set the rootDavid Barr, Oct 7, 2010
  2. Sverre RabbelierOct 7, 2010
  3. Jonathan NiederOct 7, 2010
  4. Sverre RabbelierOct 7, 2010
  5. David BarrOct 7, 2010
  6. fast-import: Allow filemodify to set the rootDavid Barr, Oct 7, 2010
  7. Sverre RabbelierOct 7, 2010
  8. Johannes SixtOct 8, 2010
  9. Jonathan NiederOct 8, 2010
  10. Johannes SixtOct 8, 2010
  11. Jonathan NiederOct 8, 2010
  12. Ramkumar RamachandraOct 8, 2010
  13. Gabriel FilionOct 8, 2010
  14. David Michael BarrOct 8, 2010
  15. Sverre RabbelierOct 8, 2010
  16. Jonathan NiederOct 8, 2010
  17. David Michael BarrOct 9, 2010
  18. Sverre RabbelierOct 9, 2010
  19. fast-import: Allow filemodify to set the rootDavid Barr, Oct 10, 2010
  20. Jonathan NiederOct 11, 2010
  21. 0/2 Re: fast-import: Allow filemodify to set the rootJonathan Nieder, Oct 18, 2010
  22. 1/2 fast-import: filemodify after M 040000 <tree> "" crashesJonathan Nieder, Oct 18, 2010
  23. Sverre RabbelierOct 18, 2010
  24. Jonathan NiederOct 18, 2010
  25. fast-import: do not clear notes in do_change_note_fanout()Jonathan Nieder, Oct 20, 2010
  26. 2/2 fast-import: tighten M 040000 syntaxJonathan Nieder, Oct 18, 2010
  27. Documentation/fast-import: put explanation of M 040000 <dataref> "" in contextJonathan Nieder, Jan 16, 2011
  28. Junio C HamanoJan 18, 2011
  29. Jonathan NiederJan 18, 2011
  30. Junio C HamanoJan 18, 2011
  31. Jonathan NiederJan 18, 2011

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