[libc-commits] [libc] Add bit width length modifier to printf (PR #82461)

[Michael Jones via libc-commits]

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@@ -169,6 +170,52 @@ TEST(LlvmLibcSPrintfTest, IntConv) {
   EXPECT_EQ(written, 20);
   ASSERT_STREQ(buff, "-9223372036854775808"); // ll min
 
+  written = LIBC_NAMESPACE::sprintf(buff, "%w3d", 5807);
+  EXPECT_EQ(written, 1);
+  ASSERT_STREQ(buff, "7");
+
+  written = LIBC_NAMESPACE::sprintf(buff, "%w3d", 1);
+  EXPECT_EQ(written, 1);
+  ASSERT_STREQ(buff, "1");
+
+  written = LIBC_NAMESPACE::sprintf(buff, "%w64d", 9223372036854775807l);
+  EXPECT_EQ(written, 19);
+  ASSERT_STREQ(buff, "9223372036854775807");
+
+  char format[64];
+  char uintmax[128];
+  LIBC_NAMESPACE::sprintf(format, "%%w%du", UINTMAX_WIDTH);
+  LIBC_NAMESPACE::sprintf(uintmax, "%ju", UINTMAX_MAX);
+  written = LIBC_NAMESPACE::sprintf(buff, format, UINTMAX_MAX);
+  EXPECT_EQ(written, static_cast<int>(strlen(uintmax)));
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michaelrj-google wrote:

you don't need to call strlen here, just use a variable to store the result from the sprintf call for `%ju` and compare against that.

https://github.com/llvm/llvm-project/pull/82461