[PATCHv2 3/3] submodule-config: clarify parsing of null_sha1 element

[Stefan Beller <sbeller@google.com>]

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
---
 Documentation/technical/api-submodule-config.txt | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/Documentation/technical/api-submodule-config.txt b/Documentation/technical/api-submodule-config.txt
index 768458580f..a91c1f085e 100644
--- a/Documentation/technical/api-submodule-config.txt
+++ b/Documentation/technical/api-submodule-config.txt
@@ -55,8 +55,11 @@ Functions
 
 	The same as above but lookup by name.
 
-If given the null_sha1 as commit_or_tree the local configuration of a
-submodule will be returned (e.g. consolidated values from local git
+Whenever a submodule configuration is parsed in `parse_submodule_config_option`
+via e.g. `gitmodules_config()`, it will be overwrite the entry with the sha1
+zeroed out.  So in the normal case, when HEAD:.gitmodules is parsed first and
+then overlayed with the repository configuration, the null_sha1 entry contains
+the local configuration of a submodule (e.g. consolidated values from local git
 configuration and the .gitmodules file in the worktree).
 
 For an example usage see test-submodule-config.c.
-- 
2.11.0.rc2.18.g0126045.dirty