From eafd990f2606431d45cf0bbdbfee6d5959628de7 Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Thu, 16 Jan 2020 19:24:34 +0100 Subject: BaseTools/Conf/gitattributes: fix "--function-context" for C source code The "--function-context" ("-W") option of git-diff displays the entire body of a modified function, not just small modified hunks within the function. It is useful for reviewers when the code changes to the function are small, but they could affect, or depend on, control flow that is far away in the same function. Of course, the size of the displayed context can be controlled with the "-U" option anyway, but such fixed-size contexts are usually either too small, or too large, in the above scenario. It turns out that "--function-context" does not work correctly for C source files in edk2. In particular, labels for the goto instruction (which the edk2 coding style places in the leftmost column) appear to terminate "--function-context". The "git" utility contains built-in hunk header patterns for the C and C++ languages. However, they do not take effect in edk2 because we don't explicitly assign the "cpp" git-diff driver to our C files. The gitattributes(5) manual explains that this is required: > There are a few built-in patterns to make this easier, and > tex is one of them, so you do not have to write the above in > your configuration file (you still need to enable this with > the attribute mechanism, via .gitattributes). The following > built in patterns are available: > > [...] > > * cpp suitable for source code in the C and C++ > languages. The key statement is the one in parentheses. Grab the suffix lists from the [C-Code-File] and [Acpi-Table-Code-File] sections of "BaseTools/Conf/build_rule.template", add "*.h" and "*.H", and mark those as belonging to the "cpp" git-diff driver. This change has a dramatic effect on the following command, for example: $ git show -W 2ef0c27cb84c Cc: Bob Feng Cc: Leif Lindholm Cc: Liming Gao Signed-off-by: Laszlo Ersek Message-Id: <20200120094245.9010-1-lersek@redhat.com> Reviewed-by: Leif Lindholm Reviewed-by: Leif Lindholm Reviewed-by: Liming Gao --- BaseTools/Conf/gitattributes | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/BaseTools/Conf/gitattributes b/BaseTools/Conf/gitattributes index 58b93e9d4c..319e890641 100644 --- a/BaseTools/Conf/gitattributes +++ b/BaseTools/Conf/gitattributes @@ -17,3 +17,14 @@ *.fdf diff=ini *.fdf.inc diff=ini *.inf diff=ini +*.c diff=cpp +*.C diff=cpp +*.cc diff=cpp +*.CC diff=cpp +*.cpp diff=cpp +*.Cpp diff=cpp +*.CPP diff=cpp +*.aslc diff=cpp +*.act diff=cpp +*.h diff=cpp +*.H diff=cpp -- cgit v1.2.3