Re: [PATCH v3 1/2] revision: document get_reference()

[Emily Shaffer <emilyshaffer@google.com>]

On Sat, Jan 11, 2020 at 02:34:55PM -0800, Jonathan Tan wrote:
> In particular, document the behavior when the object is corrupt. The
> existing behavior when parse_object() encounters a hash mismatch has
> been there since cc243c3ceb ("show: --ignore-missing", 2011-05-19), and
> the existing behavior when the code disagrees on whether an object is a
> commit has been there since ec0c5798ee ("revision: use commit graph in
> get_reference()", 2018-12-28).

Does "disagreement on whether an object is a commit" count as corrupt
object? Otherwise I'm not seeing mention of it in the comment that was
added.

> ---
>  revision.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/revision.c b/revision.c
> index 8136929e23..91ca194388 100644
> --- a/revision.c
> +++ b/revision.c
> @@ -355,6 +355,16 @@ void add_head_to_pending(struct rev_info *revs)
>  	add_pending_object(revs, obj, "HEAD");
>  }
>  
> +/*
> + * Returns the object corresponding to "oid" and sets the given flags on
> + * it.
> + *
> + * If that object is missing or corrupt, this function returns NULL if
> + * "revs" permits it (that is, if revs->ignore_missing is true or if
> + * revs->exclude_promisor_objects is true and the object is a promisor
> + * object), and dies otherwise. Note that corrupt objects are treated

The parenthetical is hard to parse. Is it "(revs->ignore_missing is
true) or (revs->exclude_promisor_objects is true and the object is a
promisor)" or something else? Maybe an extra comma,

  (that is, if revs->ignore_missing is true, or if
  revs->exclude_promisor_objects is true and the object is a promisor
  object)

> + * like missing objects, to preserve existing behavior.
> + */
>  static struct object *get_reference(struct rev_info *revs, const char *name,
>  				    const struct object_id *oid,
>  				    unsigned int flags)
> -- 
> 2.25.0.rc1.283.g88dfdc4193-goog
>