Visitar URL original
Fix #680: Add option to keep comments in preprocessed code by ludviggunne · Pull Request #681 · cppcheck-opensource/simplecpp · GitHub
Skip to content

Fix #680: Add option to keep comments in preprocessed code #681

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
ludviggunne merged 3 commits into from
Jul 24, 2026
Merged

Fix #680: Add option to keep comments in preprocessed code #681

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
939c3b8
fix
ludviggunne Jul 13, 2026
8558255
update tests
ludviggunne Jul 13, 2026
04b4e45
add test
ludviggunne Jul 13, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
3 changes: 2 additions & 1 deletion main.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -242,7 +242,8 @@ int main(int argc, char **argv)
f.close();
rawtokens = new simplecpp::TokenList(filename,files,&outputList);
}
rawtokens->removeComments();
if (dui.removeComments)
rawtokens->removeComments();
simplecpp::FileDataCache filedata;
simplecpp::preprocess(outputTokens, *rawtokens, files, filedata, dui, &outputList);
simplecpp::cleanup(filedata);
Expand Down
10 changes: 5 additions & 5 deletions simplecpp.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3341,7 +3341,7 @@ simplecpp::FileDataCache simplecpp::load(const simplecpp::TokenList &rawtokens,
return cache;
}

static bool preprocessToken(simplecpp::TokenList &output, const simplecpp::Token *&tok1, simplecpp::MacroMap &macros, std::vector<std::string> &files, simplecpp::OutputList *outputList)
static bool preprocessToken(simplecpp::TokenList &output, const simplecpp::Token *&tok1, simplecpp::MacroMap &macros, std::vector<std::string> &files, simplecpp::OutputList *outputList, const simplecpp::DUI &dui)
{
const simplecpp::Token * const tok = tok1;
const simplecpp::MacroMap::const_iterator it = tok->name ? macros.find(tok->str()) : macros.end();
Expand Down Expand Up @@ -3372,7 +3372,7 @@ static bool preprocessToken(simplecpp::TokenList &output, const simplecpp::Token
}
output.takeTokens(value);
} else {
if (!tok->comment)
if (!tok->comment || !dui.removeComments)
output.push_back(new simplecpp::Token(*tok));
tok1 = tok->next;
}
Expand Down Expand Up @@ -3647,7 +3647,7 @@ void simplecpp::preprocess(simplecpp::TokenList &output, const simplecpp::TokenL
TokenList inc2(files);
if (!inc1.empty() && inc1.cfront()->name) {
const Token *inctok = inc1.cfront();
if (!preprocessToken(inc2, inctok, macros, files, outputList)) {
if (!preprocessToken(inc2, inctok, macros, files, outputList, dui)) {
output.clear();
return;
}
Expand Down Expand Up @@ -3817,7 +3817,7 @@ void simplecpp::preprocess(simplecpp::TokenList &output, const simplecpp::TokenL
maybeUsedMacros[rawtok->next->str()].emplace_back(rawtok->next->location);

const Token *tmp = tok;
if (!preprocessToken(expr, tmp, macros, files, outputList)) {
if (!preprocessToken(expr, tmp, macros, files, outputList, dui)) {
output.clear();
return;
}
Expand Down Expand Up @@ -3915,7 +3915,7 @@ void simplecpp::preprocess(simplecpp::TokenList &output, const simplecpp::TokenL
const Location loc(rawtok->location);
TokenList tokens(files);

if (!preprocessToken(tokens, rawtok, macros, files, outputList)) {
if (!preprocessToken(tokens, rawtok, macros, files, outputList, dui)) {
output.clear();
return;
}
Expand Down
37 changes: 33 additions & 4 deletions test.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -517,12 +517,15 @@ static void combineOperators_ellipsis()

static void comment()
{
simplecpp::DUI dui;
dui.removeComments = true;

ASSERT_EQUALS("// abc", readfile("// abc"));
ASSERT_EQUALS("", preprocess("// abc"));
ASSERT_EQUALS("", preprocess("// abc", dui));
ASSERT_EQUALS("/*\n\n*/abc", readfile("/*\n\n*/abc"));
ASSERT_EQUALS("\n\nabc", preprocess("/*\n\n*/abc"));
ASSERT_EQUALS("\n\nabc", preprocess("/*\n\n*/abc", dui));
ASSERT_EQUALS("* p = a / * b / * c ;", readfile("*p=a/ *b/ *c;"));
ASSERT_EQUALS("* p = a / * b / * c ;", preprocess("*p=a/ *b/ *c;"));
ASSERT_EQUALS("* p = a / * b / * c ;", preprocess("*p=a/ *b/ *c;", dui));
}

static void comment_multiline()
Expand Down Expand Up @@ -562,6 +565,27 @@ static void comment_multiline()
ASSERT_EQUALS("// abc\ndef", readfile("// abc\\\ndef"));
}

static void keep_comments()
{
simplecpp::DUI dui;
dui.removeComments = false;

{
const char code[] = "/* comment */\n";
ASSERT_EQUALS("/* comment */", preprocess(code,dui));
}

{
const char code[] = "// comment\n";
ASSERT_EQUALS("// comment", preprocess(code,dui));
}

{
const char code[] = "#define MACRO /* comment */\nMACRO\n";
ASSERT_EQUALS("\n/* comment */", preprocess(code,dui));

@danmar danmar Jul 13, 2026

Copy link
Copy Markdown
Collaborator

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

this may be questionable. do we want that comments are expanded. maybe the comment should only be kept on line 1.

but for now .. as far as I see it does not matter much. If somebody has strong opinions later and wants to change I am not against changing..

@ludviggunne ludviggunne Jul 15, 2026

Copy link
Copy Markdown
Collaborator Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

gcc does copy comments in expansions. it will however turn c++-style comments in to c-style comments: https://gcc.gnu.org/onlinedocs/gcc/Preprocessor-Options.html

}
}


static void constFold()
{
Expand Down Expand Up @@ -2568,13 +2592,16 @@ static void location11()

static void location12()
{
simplecpp::DUI dui;
dui.removeComments = true;

const char code[] =
"/**//**/#/**//**/line/**//**/3/**//**/\"file.c\"/**/\n"
"__LINE__ __FILE__\n";
ASSERT_EQUALS("\n"
"#line 3 \"file.c\"\n"
"3 \"file.c\"",
preprocess(code));
preprocess(code, dui));
}

static void missingHeader1()
Expand Down Expand Up @@ -3012,6 +3039,7 @@ static void include9()
simplecpp::TokenList out(files);
simplecpp::DUI dui;
dui.includePaths.emplace_back(".");
dui.removeComments = true;
simplecpp::preprocess(out, rawtokens_c, files, cache, dui);

ASSERT_EQUALS("\n#line 2 \"1.h\"\nx = 1 ;", out.stringify());
Expand Down Expand Up @@ -4066,6 +4094,7 @@ static void runTests(int argc, char **argv, Input input)

TEST_CASE(comment);
TEST_CASE(comment_multiline);
TEST_CASE(keep_comments);

TEST_CASE(constFold);

Expand Down
Loading