[libc] Add islower and isupper implementation.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D84960

6 files changed, 76 insertions, 26 deletions

diff --git a/libc/test/src/ctype/CMakeLists.txt b/libc/test/src/ctype/CMakeLists.txt
index 7834746ab1d7..c9959465c697 100644
--- a/libc/test/src/ctype/CMakeLists.txt
+++ b/libc/test/src/ctype/CMakeLists.txt
@@ -29,3 +29,23 @@ add_libc_unittest(
   DEPENDS
     libc.src.ctype.isdigit
 )
+
+add_libc_unittest(
+  islower
+  SUITE
+    libc_ctype_unittests
+  SRCS
+    islower_test.cpp
+  DEPENDS
+    libc.src.ctype.islower
+)
+
+add_libc_unittest(
+  isupper
+  SUITE
+    libc_ctype_unittests
+  SRCS
+    isupper_test.cpp
+  DEPENDS
+    libc.src.ctype.isupper
+)
diff --git a/libc/test/src/ctype/isalnum_test.cpp b/libc/test/src/ctype/isalnum_test.cpp
index 1c4ad7d3ff8a..ca77285c5614 100644
--- a/libc/test/src/ctype/isalnum_test.cpp
+++ b/libc/test/src/ctype/isalnum_test.cpp
@@ -7,21 +7,17 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/ctype/isalnum.h"
-#include "utils/UnitTest/Test.h"
 
-// Helper function that makes a call to isalnum a bit cleaner
-// for use with testing utilities, since it explicitly requires
-// a boolean value for EXPECT_TRUE and EXPECT_FALSE.
-bool call_isalnum(int c) { return __llvm_libc::isalnum(c); }
+#include "utils/UnitTest/Test.h"
 
 TEST(IsAlNum, DefaultLocale) {
   // Loops through all characters, verifying that numbers and letters
-  // return true and everything else returns false.
+  // return non-zero integer and everything else returns a zero.
   for (int c = 0; c < 255; ++c) {
     if (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z') ||
         ('0' <= c && c <= '9'))
-      EXPECT_TRUE(call_isalnum(c));
+      EXPECT_NE(__llvm_libc::isalnum(c), 0);
     else
-      EXPECT_FALSE(call_isalnum(c));
+      EXPECT_EQ(__llvm_libc::isalnum(c), 0);
   }
 }
diff --git a/libc/test/src/ctype/isalpha_test.cpp b/libc/test/src/ctype/isalpha_test.cpp
index 81fc7248f871..d91219b50406 100644
--- a/libc/test/src/ctype/isalpha_test.cpp
+++ b/libc/test/src/ctype/isalpha_test.cpp
@@ -7,20 +7,16 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/ctype/isalpha.h"
-#include "utils/UnitTest/Test.h"
 
-// Helper function that makes a call to isalpha a bit cleaner
-// for use with testing utilities, since it explicitly requires
-// a boolean value for EXPECT_TRUE and EXPECT_FALSE.
-bool call_isalpha(int c) { return __llvm_libc::isalpha(c); }
+#include "utils/UnitTest/Test.h"
 
 TEST(IsAlpha, DefaultLocale) {
-  // Loops through all characters, verifying that letters return true
-  // and everything else returns false.
+  // Loops through all characters, verifying that letters return a
+  // non-zero integer and everything else returns zero.
   for (int ch = 0; ch < 255; ++ch) {
     if (('a' <= ch && ch <= 'z') || ('A' <= ch && ch <= 'Z'))
-      EXPECT_TRUE(call_isalpha(ch));
+      EXPECT_NE(__llvm_libc::isalpha(ch), 0);
     else
-      EXPECT_FALSE(call_isalpha(ch));
+      EXPECT_EQ(__llvm_libc::isalpha(ch), 0);
   }
 }
diff --git a/libc/test/src/ctype/isdigit_test.cpp b/libc/test/src/ctype/isdigit_test.cpp
index 6fea9564db67..2430a92425c4 100644
--- a/libc/test/src/ctype/isdigit_test.cpp
+++ b/libc/test/src/ctype/isdigit_test.cpp
@@ -7,20 +7,16 @@
 //===----------------------------------------------------------------------===//
 
 #include "src/ctype/isdigit.h"
-#include "utils/UnitTest/Test.h"
 
-// Helper function that makes a call to isdigit a bit cleaner
-// for use with testing utilities, since it explicitly requires
-// a boolean value for EXPECT_TRUE and EXPECT_FALSE.
-bool call_isdigit(int c) { return __llvm_libc::isdigit(c); }
+#include "utils/UnitTest/Test.h"
 
 TEST(IsDigit, DefaultLocale) {
-  // Loops through all characters, verifying that numbers return true
-  // and everything else returns false.
+  // Loops through all characters, verifying that numbers return a
+  // non-zero integer and everything else returns zero.
   for (int ch = 0; ch < 255; ++ch) {
     if ('0' <= ch && ch <= '9')
-      EXPECT_TRUE(call_isdigit(ch));
+      EXPECT_NE(__llvm_libc::isdigit(ch), 0);
     else
-      EXPECT_FALSE(call_isdigit(ch));
+      EXPECT_EQ(__llvm_libc::isdigit(ch), 0);
   }
 }
diff --git a/libc/test/src/ctype/islower_test.cpp b/libc/test/src/ctype/islower_test.cpp
new file mode 100644
index 000000000000..9b38cabc67aa
--- /dev/null
+++ b/libc/test/src/ctype/islower_test.cpp
@@ -0,0 +1,21 @@
+//===-- Unittests for islower----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/ctype/islower.h"
+#include "utils/UnitTest/Test.h"
+
+TEST(IsLower, DefaultLocale) {
+  // Loops through all characters, verifying that lowercase letters
+  // return a non-zero integer and everything else returns zero.
+  for (int ch = 0; ch < 255; ++ch) {
+    if ('a' <= ch && ch <= 'z')
+      EXPECT_NE(__llvm_libc::islower(ch), 0);
+    else
+      EXPECT_EQ(__llvm_libc::islower(ch), 0);
+  }
+}
diff --git a/libc/test/src/ctype/isupper_test.cpp b/libc/test/src/ctype/isupper_test.cpp
new file mode 100644
index 000000000000..0a13f4e11b0e
--- /dev/null
+++ b/libc/test/src/ctype/isupper_test.cpp
@@ -0,0 +1,21 @@
+//===-- Unittests for isupper----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/ctype/isupper.h"
+#include "utils/UnitTest/Test.h"
+
+TEST(IsUpper, DefaultLocale) {
+  // Loops through all characters, verifying that uppercase letters
+  // return a non-zero integer and everything else returns zero.
+  for (int ch = 0; ch < 255; ++ch) {
+    if ('A' <= ch && ch <= 'Z')
+      EXPECT_NE(__llvm_libc::isupper(ch), 0);
+    else
+      EXPECT_EQ(__llvm_libc::isupper(ch), 0);
+  }
+}