git, branch v2.0.4

Git 2.0.4

2014-07-30T21:19:53Z

Signed-off-by: Junio C Hamano

commit --amend: test specifies authorship but forgets to check

2014-07-30T18:32:12Z

The test case "--amend option copies authorship" specifies that the git-commit option `--amend` uses the authorship of the replaced commit for the new commit. Add the omitted check that this property actually holds. Signed-off-by: Fabian Ruch Signed-off-by: Junio C Hamano

t4013: test diff-tree's --stdin commit formatting

2014-07-28T18:31:32Z

Once upon a time, git-log was just "rev-list | diff-tree", and we did not bother to test it separately. These days git-log is implemented internally, but we want to make sure that the rev-list to diff-tree pipeline continues to function. Let's add a basic sanity test. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

Merge branch 'jk/alloc-commit-id-maint' into maint

2014-07-28T17:35:35Z

* jk/alloc-commit-id-maint: diff-tree: avoid lookup_unknown_object object_as_type: set commit index alloc: factor out commit index add object_as_type helper for casting objects parse_object_buffer: do not set object type move setting of object->type to alloc_* functions alloc: write out allocator definitions alloc.c: remove the alloc_raw_commit_node() function

diff-tree: avoid lookup_unknown_object

2014-07-28T17:14:34Z

We generally want to avoid lookup_unknown_object, because it results in allocating more memory for the object than may be strictly necessary. In this case, it is used to check whether we have an already-parsed object before calling parse_object, to save us from reading the object from disk. Using lookup_object would be fine for that purpose, but we can take it a step further. Since this code was written, parse_object already learned the "check lookup_object" optimization, so we can simply call parse_object directly. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

object_as_type: set commit index

2014-07-28T17:14:34Z

The point of the "index" field of struct commit is that every allocated commit would have one. It is supposed to be an invariant that whenever object->type is set to OBJ_COMMIT, we have a unique index. Commit 969eba6 (commit: push commit_index update into alloc_commit_node, 2014-06-10) covered this case for newly-allocated commits. However, we may also allocate an "unknown" object via lookup_unknown_object, and only later convert it to a commit. We must make sure that we set the commit index when we switch the type field. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

alloc: factor out commit index

2014-07-28T17:14:33Z

We keep a static counter to set the commit index on newly allocated objects. However, since we also need to set the index on any_objects which are converted to commits, let's make the counter available as a public function. While we're moving it, let's make sure the counter is allocated as an unsigned integer to match the index field in "struct commit". Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

add object_as_type helper for casting objects

2014-07-28T17:14:33Z

When we call lookup_commit, lookup_tree, etc, the logic goes something like: 1. Look for an existing object struct. If we don't have one, allocate and return a new one. 2. Double check that any object we have is the expected type (and complain and return NULL otherwise). 3. Convert an object with type OBJ_NONE (from a prior call to lookup_unknown_object) to the expected type. We can encapsulate steps 2 and 3 in a helper function which checks whether we have the expected object type, converts OBJ_NONE as appropriate, and returns the object. Not only does this shorten the code, but it also provides one central location for converting OBJ_NONE objects into objects of other types. Future patches will use that to enforce type-specific invariants. Since this is a refactoring, we would want it to behave exactly as the current code. It takes a little reasoning to see that this is the case: - for lookup_{commit,tree,etc} functions, we are just pulling steps 2 and 3 into a function that does the same thing. - for the call in peel_object, we currently only do step 3 (but we want to consolidate it with the others, as mentioned above). However, step 2 is a noop here, as the surrounding conditional makes sure we have OBJ_NONE (which we want to keep to avoid an extraneous call to sha1_object_info). - for the call in lookup_commit_reference_gently, we are currently doing step 2 but not step 3. However, step 3 is a noop here. The object we got will have just come from deref_tag, which must have figured out the type for each object in order to know when to stop peeling. Therefore the type will never be OBJ_NONE. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

parse_object_buffer: do not set object type

2014-07-28T17:14:33Z

The only way that "obj" can be non-NULL is if it came from one of the lookup_* functions. These functions always ensure that the object has the expected type (and return NULL otherwise), so there is no need for us to set the type. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano

move setting of object->type to alloc_* functions

2014-07-28T17:14:33Z

The "struct object" type implements basic object polymorphism. Individual instances are allocated as concrete types (or as a union type that can store any object), and a "struct object *" can be cast into its real type after examining its "type" enum. This means it is dangerous to have a type field that does not match the allocation (e.g., setting the type field of a "struct blob" to "OBJ_COMMIT" would mean that a reader might read past the allocated memory). In most of the current code this is not a problem; the first thing we do after allocating an object is usually to set its type field by passing it to create_object. However, the virtual commits we create in merge-recursive.c do not ever get their type set. This does not seem to have caused problems in practice, though (presumably because we always pass around a "struct commit" pointer and never even look at the type). We can fix this oversight and also make it harder for future code to get it wrong by setting the type directly in the object allocation functions. This will also make it easier to fix problems with commit index allocation, as we know that any object allocated by alloc_commit_node will meet the invariant that an object with an OBJ_COMMIT type field will have a unique index number. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano