Re: [PATCH] checkpatch: Require commit text and warn on long commit text lines

[pheragu@codeaurora.org]

On 2018-07-13 17:08, Joe Perches wrote:
> On Fri, 2018-07-13 at 16:28 -0700, pheragu@codeaurora.org wrote:
>> On 2018-07-13 14:46, Joe Perches wrote:
>> > On Fri, 2018-07-13 at 14:40 -0700, Prakruthi Deepak Heragu wrote:
>> > > Commit text is almost always necessary to explain why a change is
>> > > needed.
>> >
>> > This bit seems sensible, but perhaps it should just count the
>> > number of lines after the end of email headers and before any
>> > Signed-off-by:/Signature line
>> >
>> 
>> While committing the changes, one can just write the subject and not
>> write
>> the commit text at all. So, if we just count the lines between email
>> headers
>> and signed-off, we still do count lines which form the subject, but 
>> the
>> commit text is still absent. Also, subject can be longer than one 
>> line.
>> So,
>> just counting lines doesn't really guarantee the presence of commit
>> text.
> 
> Not true.
> Look at $in_header_lines and $in_commit_log.
> 
>> > > Also, warn on commit text lines longer than 75 characters. The commit
>> > > text
>> > > are indented and may wrap on a terminal if they are longer than 75
>> > > characters.
>> >
>> > This is already exists via
>> >
>> > # Check for line lengths > 75 in commit log, warn once
>> > 		if ($in_commit_log && !$commit_log_long_line &&
>> > 		    length($line) > 75 &&
>> >
>> 
>> True, but this patch points out every line of the commit text that is
>> exceeding the limit.
> 
> Which is bad because things like dump_stack() are added in
> commit logs and those are already allowed to be > 75 chars.
> 
> Anyway, something like this probably works.  Please test.
> ---
>  scripts/checkpatch.pl | 13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
> index b5c875d7132b..8b5f3dae31c9 100755
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -2240,6 +2240,7 @@ sub process {
>  	my $in_header_lines = $file ? 0 : 1;
>  	my $in_commit_log = 0;		#Scanning lines before patch
>  	my $has_commit_log = 0;		#Encountered lines before patch
> +	my $commit_log_lines = 0;	#Number of commit log lines
>  	my $commit_log_possible_stack_dump = 0;
>  	my $commit_log_long_line = 0;
>  	my $commit_log_has_diff = 0;
> @@ -2497,6 +2498,18 @@ sub process {
> 
>  		$cnt_lines++ if ($realcnt != 0);
> 
> +# Verify the existence of a commit log if appropriate
> +# 2 is used because a $signature is counted in $commit_log_lines
> +		if ($in_commit_log) {
> +			if ($line !~ /^\s*$/) {
> +				$commit_log_lines++;	#could be a $signature
> +			}
> +		} else if ($has_commit_log && $commit_log_lines < 2) {
> +			WARN("COMMIT_MESSAGE",
> +			     "Missing commit description - Add an appropriate one\n");
> +			$commit_log_lines = 2;	#warn only once
> +		}
> +
>  # Check if the commit log has what seems like a diff which can confuse 
> patch
>  		if ($in_commit_log && !$commit_log_has_diff &&
>  		    (($line =~ m@^\s+diff\b.*a/[\w/]+@ &&
I checked all the cases that I mentioned before. The change you 
suggested works
for every case. Would you take care of merging this fix?