parseShebangs: Make strings with backtick sequences representable

This commit is contained in:
Robert Hensing 2023-11-06 18:19:14 +01:00 committed by tomberek
parent ffd414eb75
commit 589d338776
4 changed files with 129 additions and 3 deletions

View file

@ -189,12 +189,40 @@ void ParseQuoted::operator()(std::shared_ptr<Parser> &state, Strings & r) {
throw Error("unterminated quoted string in nix shebang");
}
switch (remaining[0]) {
case ' ':
if ((remaining.size() == 3 && remaining[1] == '`' && remaining[2] == '`')
|| (remaining.size() > 3 && remaining[1] == '`' && remaining[2] == '`' && remaining[3] != '`')) {
// exactly two backticks mark the end of a quoted string, but a preceding space is ignored if present.
state = std::make_shared<ParseUnquoted>(ParseUnquoted(remaining.substr(3)));
r.push_back(acc);
return;
}
else {
// just a normal space
acc += remaining[0];
remaining = remaining.substr(1);
return;
}
case '`':
if (remaining.size() > 1 && remaining[1] == '`') {
// exactly two backticks mark the end of a quoted string
if ((remaining.size() == 2 && remaining[1] == '`')
|| (remaining.size() > 2 && remaining[1] == '`' && remaining[2] != '`')) {
state = std::make_shared<ParseUnquoted>(ParseUnquoted(remaining.substr(2)));
r.push_back(acc);
return;
}
// a sequence of at least 3 backticks is one escape-backtick which is ignored, followed by any number of backticks, which are verbatim
else if (remaining.size() >= 3 && remaining[1] == '`' && remaining[2] == '`') {
// ignore "escape" backtick
remaining = remaining.substr(1);
// add the rest
while (remaining.size() > 0 && remaining[0] == '`') {
acc += '`';
remaining = remaining.substr(1);
}
return;
}
else {
acc += remaining[0];
remaining = remaining.substr(1);
@ -208,7 +236,7 @@ void ParseQuoted::operator()(std::shared_ptr<Parser> &state, Strings & r) {
assert(false);
}
static Strings parseShebangContent(std::string_view s) {
Strings parseShebangContent(std::string_view s) {
Strings result;
std::shared_ptr<Parser> parserState(std::make_shared<ParseUnquoted>(ParseUnquoted(s)));

View file

@ -409,4 +409,6 @@ public:
virtual void add(std::string completion, std::string description = "") = 0;
};
Strings parseShebangContent(std::string_view s);
}

94
src/libutil/tests/args.cc Normal file
View file

@ -0,0 +1,94 @@
#include "../args.hh"
#include <list>
#include <gtest/gtest.h>
namespace nix {
TEST(parseShebangContent, basic) {
std::list<std::string> r = parseShebangContent("hi there");
ASSERT_EQ(r.size(), 2);
auto i = r.begin();
ASSERT_EQ(*i++, "hi");
ASSERT_EQ(*i++, "there");
}
TEST(parseShebangContent, empty) {
std::list<std::string> r = parseShebangContent("");
ASSERT_EQ(r.size(), 0);
}
TEST(parseShebangContent, doubleBacktick) {
std::list<std::string> r = parseShebangContent("``\"ain't that nice\"``");
ASSERT_EQ(r.size(), 1);
auto i = r.begin();
ASSERT_EQ(*i++, "\"ain't that nice\"");
}
TEST(parseShebangContent, doubleBacktickEmpty) {
std::list<std::string> r = parseShebangContent("````");
ASSERT_EQ(r.size(), 1);
auto i = r.begin();
ASSERT_EQ(*i++, "");
}
TEST(parseShebangContent, doubleBacktickMarkdownInlineCode) {
std::list<std::string> r = parseShebangContent("``# I'm markdown section about `coolFunction` ``");
ASSERT_EQ(r.size(), 1);
auto i = r.begin();
ASSERT_EQ(*i++, "# I'm markdown section about `coolFunction`");
}
TEST(parseShebangContent, doubleBacktickMarkdownCodeBlockNaive) {
std::list<std::string> r = parseShebangContent("``Example 1\n```nix\na: a\n``` ``");
auto i = r.begin();
ASSERT_EQ(r.size(), 1);
ASSERT_EQ(*i++, "Example 1\n``nix\na: a\n``");
}
TEST(parseShebangContent, doubleBacktickMarkdownCodeBlockCorrect) {
std::list<std::string> r = parseShebangContent("``Example 1\n````nix\na: a\n```` ``");
auto i = r.begin();
ASSERT_EQ(r.size(), 1);
ASSERT_EQ(*i++, "Example 1\n```nix\na: a\n```");
}
TEST(parseShebangContent, doubleBacktickMarkdownCodeBlock2) {
std::list<std::string> r = parseShebangContent("``Example 1\n````nix\na: a\n````\nExample 2\n````nix\na: a\n```` ``");
auto i = r.begin();
ASSERT_EQ(r.size(), 1);
ASSERT_EQ(*i++, "Example 1\n```nix\na: a\n```\nExample 2\n```nix\na: a\n```");
}
TEST(parseShebangContent, singleBacktickInDoubleBacktickQuotes) {
std::list<std::string> r = parseShebangContent("``` ``");
auto i = r.begin();
ASSERT_EQ(r.size(), 1);
ASSERT_EQ(*i++, "`");
}
TEST(parseShebangContent, singleBacktickAndSpaceInDoubleBacktickQuotes) {
std::list<std::string> r = parseShebangContent("``` ``");
auto i = r.begin();
ASSERT_EQ(r.size(), 1);
ASSERT_EQ(*i++, "` ");
}
TEST(parseShebangContent, doubleBacktickInDoubleBacktickQuotes) {
std::list<std::string> r = parseShebangContent("````` ``");
auto i = r.begin();
ASSERT_EQ(r.size(), 1);
ASSERT_EQ(*i++, "``");
}
TEST(parseShebangContent, increasingQuotes) {
std::list<std::string> r = parseShebangContent("```` ``` `` ````` `` `````` ``");
auto i = r.begin();
ASSERT_EQ(r.size(), 4);
ASSERT_EQ(*i++, "");
ASSERT_EQ(*i++, "`");
ASSERT_EQ(*i++, "``");
ASSERT_EQ(*i++, "```");
}
}

View file

@ -243,7 +243,9 @@ in [`nix help-stores`](./nix3-help-stores.md).
The `nix` command can be used as a `#!` interpreter.
Arguments to Nix can be passed on subsequent lines in the script.
Verbatim strings may be passed in double backtick (```` `` ````) quotes.
Verbatim strings may be passed in double backtick (```` `` ````) quotes. <!-- that's markdown for two backticks in inline code. -->
Sequences of _n_ backticks of 3 or longer are parsed as _n-1_ literal backticks.
A single space before the closing ```` `` ```` is ignored if present.
`--file` and `--expr` resolve relative paths based on the script location.