add an impl of Expr::show for ExprInheritFrom that doesn't crash

ExprVar::show() assumes it has a name. dynamic inherits do not
necessarily (ever?) have a name.

Change-Id: If10893188e307431da17f0c1bd0787adc74f7141
This commit is contained in:
Qyriad 2024-06-24 14:33:12 -06:00
parent 3f6bfcc930
commit 3705b31ed5
4 changed files with 45 additions and 1 deletions

View file

@ -50,6 +50,16 @@ void ExprVar::show(const SymbolTable & symbols, std::ostream & str) const
str << symbols[name];
}
void ExprInheritFrom::show(SymbolTable const & symbols, std::ostream & str) const
{
if (name) {
str << symbols[name];
} else {
// We can't get at the actual dynamic expression from here.
str << "(dynamic inherit)";
}
}
void ExprSelect::show(const SymbolTable & symbols, std::ostream & str) const
{
str << "(";

View file

@ -154,7 +154,8 @@ struct ExprInheritFrom : ExprVar
this->fromWith = nullptr;
}
void bindVars(EvalState & es, const std::shared_ptr<const StaticEnv> & env);
void show(SymbolTable const & symbols, std::ostream & str) const override;
void bindVars(EvalState & es, const std::shared_ptr<const StaticEnv> & env) override;
};
struct ExprSelect : Expr

View file

@ -0,0 +1,32 @@
#include <sstream>
#include <string_view>
#include <gtest/gtest.h>
#include "tests/libexpr.hh"
#include "nixexpr.hh"
namespace nix
{
using namespace testing;
struct ExprPrintingTests : LibExprTest
{
void test(Expr const & expr, std::string_view expected)
{
std::stringstream out;
expr.show(state.symbols, out);
ASSERT_EQ(out.str(), expected);
}
};
TEST_F(ExprPrintingTests, ExprInheritFrom)
{
// ExprInheritFrom has its own show() impl.
// If it uses its parent class's impl it will crash.
ExprInheritFrom const eInheritFrom(noPos, 0);
test(eInheritFrom, "(dynamic inherit)");
}
}

View file

@ -185,6 +185,7 @@ libexpr_tests_sources = files(
'libexpr/primops.cc',
'libexpr/search-path.cc',
'libexpr/trivial.cc',
'libexpr/expr-print.cc',
'libexpr/value/context.cc',
'libexpr/value/print.cc',
)