@matheusbsbs / matheus-bagliano / commits / 31399a6b61

config: allow tweaking whitespace between value and comment

Extending the previous step, this allows the whitespace placed after the value before the "# comment message" to be tweaked by tweaking the preprocessing rule to: * If the given comment string begins with one or more whitespace characters followed by '#', it is passed intact. * If the given comment string begins with '#', a Space is prepended. * Otherwise, " # " (Space, '#', Space) is prefixed. * A string with LF in it cannot be used as a comment string. Unlike the previous step, which unconditionally added a space after the value before writing the "# comment string", because the above preprocessing already gives a whitespace before the '#', the resulting string is written immediately after copying the value. And the sanity checking rule becomes * comment string after the above massaging that comes into git_config_set_multivar_in_file_gently() must - begin with zero or more whitespace characters followed by '#'. - not have a LF in it. I personally think this is over-engineered, but since I thought things through anyway, here it is in the patch form. The logic to tweak end-user supplied comment string is encapsulated in a new helper function, git_config_prepare_comment_string(), so if new front-end callers would want to use the same massaging rules, it is easily reused. Unfortunately I do not think of a way to tweak the preprocessing rules further to optionally allow having no blank after the value, i.e. to produce [section] variable = value#comment (which is a valid way to say section.variable=value, by the way) without sacrificing the ergonomics for the more usual case, so this time I really stop here. Signed-off-by: Junio C Hamano <gitster@pobox.com>

Junio C Hamano committed Mar 15, 2024 at 15:26 UTC 31399a6b6166cf76cc533bc9915878211607ed80

5 files changed +76 -20

Documentation/git-config.txt

+9 -3

@@ -89,9 +89,15 @@ OPTIONS

90 --comment <message>::

91 Append a comment at the end of new or modified lines.

92 - Unless _<message>_ begins with "#", a string "# " (hash

93 - followed by a space) is prepended to it. The _<message>_ must not

94 - contain linefeed characters (no multi-line comments are permitted).

92 +

93 + If _<message>_ begins with one or more whitespaces followed

94 + by "#", it is used as-is. If it begins with "#", a space is

95 + prepended before it is used. Otherwise, a string " # " (a

96 + space followed by a hash followed by a space) is prepended

97 + to it. And the resulting string is placed immediately after

98 + the value defined for the variable. The _<message>_ must

99 + not contain linefeed characters (no multi-line comments are

100 + permitted).

101

102 --get::

103 Get the value for a given key (optionally filtered by a regex

builtin/config.c

+1 -6

@@ -841,12 +841,7 @@ int cmd_config(int argc, const char **argv, const char *prefix)

841 flags |= CONFIG_FLAGS_FIXED_VALUE;

842 }

843

844 - if (comment) {

845 - if (strchr(comment, '\n'))

846 - die(_("no multi-line comment allowed: '%s'"), comment);

847 - if (comment[0] != '#')

848 - comment = xstrfmt("# %s", comment);

849 - }

844 + comment = git_config_prepare_comment_string(comment);

845

846 if (actions & PAGING_ACTIONS)

847 setup_auto_pager("config", 1);

config.c

+58 -11

@@ -3044,7 +3044,7 @@ static ssize_t write_pair(int fd, const char *key, const char *value,

3044 }

3045

3046 if (comment)

3047 - strbuf_addf(&sb, "%s %s\n", quote, comment);

3047 + strbuf_addf(&sb, "%s%s\n", quote, comment);

3048 else

3049 strbuf_addf(&sb, "%s\n", quote);

3050

@@ -3172,6 +3172,62 @@ void git_config_set(const char *key, const char *value)

3172 trace2_cmd_set_config(key, value);

3173 }

3174

3175 +/*

3176 + * The ownership rule is that the caller will own the string

3177 + * if it receives a piece of memory different from what it passed

3178 + * as the parameter.

3179 + */

3180 +const char *git_config_prepare_comment_string(const char *comment)

3181 +{

3182 + size_t leading_blanks;

3183 +

3184 + if (!comment)

3185 + return NULL;

3186 +

3187 + if (strchr(comment, '\n'))

3188 + die(_("no multi-line comment allowed: '%s'"), comment);

3189 +

3190 + /*

3191 + * If it begins with one or more leading whitespace characters

3192 + * followed by '#", the comment string is used as-is.

3193 + *

3194 + * If it begins with '#', a SP is inserted between the comment

3195 + * and the value the comment is about.

3196 + *

3197 + * Otherwise, the value is followed by a SP followed by '#'

3198 + * followed by SP and then the comment string comes.

3199 + */

3200 +

3201 + leading_blanks = strspn(comment, " \t");

3202 + if (leading_blanks && comment[leading_blanks] == '#')

3203 + ; /* use it as-is */

3204 + else if (comment[0] == '#')

3205 + comment = xstrfmt(" %s", comment);

3206 + else

3207 + comment = xstrfmt(" # %s", comment);

3208 +

3209 + return comment;

3210 +}

3211 +

3212 +static void validate_comment_string(const char *comment)

3213 +{

3214 + size_t leading_blanks;

3215 +

3216 + if (!comment)

3217 + return;

3218 + /*

3219 + * The front-end must have massaged the comment string

3220 + * properly before calling us.

3221 + */

3222 + if (strchr(comment, '\n'))

3223 + BUG("multi-line comments are not permitted: '%s'", comment);

3224 +

3225 + leading_blanks = strspn(comment, " \t");

3226 + if (!leading_blanks || comment[leading_blanks] != '#')

3227 + BUG("comment must begin with one or more SP followed by '#': '%s'",

3228 + comment);

3229 +}

3230 +

3231 /*

3232 * If value==NULL, unset in (remove from) config,

3233 * if value_pattern!=NULL, disregard key/value pairs where value does not match.

@@ -3211,16 +3267,7 @@ int git_config_set_multivar_in_file_gently(const char *config_filename,

3267 size_t contents_sz;

3268 struct config_store_data store = CONFIG_STORE_INIT;

3269

3214 - if (comment) {

3215 - /*

3216 - * The front-end must have massaged the comment string

3217 - * properly before calling us.

3218 - */

3219 - if (strchr(comment, '\n'))

3220 - BUG("multi-line comments are not permitted: '%s'", comment);

3221 - if (comment[0] != '#')

3222 - BUG("comment should begin with '#': '%s'", comment);

3223 - }

3270 + validate_comment_string(comment);

3271

3272 /* parse-key returns negative; flip the sign to feed exit(3) */

3273 ret = 0 - git_config_parse_key(key, &store.key, &store.baselen);

config.h

@@ -338,6 +338,8 @@ void git_config_set_multivar(const char *, const char *, const char *, unsigned)

338 int repo_config_set_multivar_gently(struct repository *, const char *, const char *, const char *, unsigned);

339 int git_config_set_multivar_in_file_gently(const char *, const char *, const char *, const char *, const char *, unsigned);

340

341 +const char *git_config_prepare_comment_string(const char *);

342 +

343 /**

344 * takes four parameters:

345 *

t/t1300-config.sh

@@ -74,6 +74,8 @@ cat > expect << EOF

74 penguin = gentoo # Pygoscelis papua

75 disposition = peckish # find fish

76 foo = bar #abc

77 + spsp = value # and comment

78 + htsp = value # and comment

79 [Sections]

80 WhatEver = Second

81 EOF

@@ -82,6 +84,10 @@ test_expect_success 'append comments' '

84 git config --replace-all --comment="Pygoscelis papua" section.penguin gentoo &&