[libc-commits] [libc] [libc] Support C23 'b' (binary) modifier in printf (PR #80851)

[via libc-commits]

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@@ -210,6 +210,20 @@ TEST_F(LlvmLibcPrintfConverterTest, HexConversion) {
   ASSERT_EQ(writer.get_chars_written(), 18);
 }
 
+TEST_F(LlvmLibcPrintfConverterTest, BinaryConversion) {
+  LIBC_NAMESPACE::printf_core::FormatSection section;
+  section.has_conv = true;
+  section.raw_string = "%b";
+  section.conv_name = 'b';
+  section.conv_val_raw = 42;
+  LIBC_NAMESPACE::printf_core::convert(&writer, section);
+
+  wb.buff[wb.buff_cur] = '\0';
+
+  ASSERT_STREQ(str, "101010");
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michaelrj-google wrote:

This is fine as a start, but it's important to have complete tests. 

Most of the functionality tests are in `sprintf_test.cpp`, so I'd recommend adding a set of tests there. You can use the `HexConv` tests as a base.

https://github.com/llvm/llvm-project/pull/80851