Add tests for check_whitespace

This adds GTest tests for both the `strip()` and `check_whitespace()` functions.

I had to do some restructuring here, creating `check_whitespace.h` and moving `main()` out to `main.c`.

I also had a bunch of compiler warnings about type conversions; changing a bunch of things from `char*` to `char const *` made that better.

This is the important first step in adding GitHub Actions for this lab.

Author: NicMcPhee

.gitignore

@@ -1,5 +1,6 @@
 # Don't commit the executable
 check_whitespace
+check_whitespace_test
 
 # Created by https://www.toptal.com/developers/gitignore/api/c,code,emacs,vim
 # Edit at https://www.toptal.com/developers/gitignore?templates=c,code,emacs,vim

.vscode/settings.json

@@ -4,6 +4,7 @@
         "calloc",
         "cmockery",
         "malloc",
+        "STREQ",
         "structs",
         "valgrind"
     ]

check_whitespace.c

@@ -6,7 +6,7 @@
  * Strips spaces from both the front and back of a string,
  * leaving any internal spaces alone.
  */
-char* strip(char* str) {
+char const *strip(char const *str) {
   int size = strlen(str);
 
   // This counts the number of leading and trailing spaces
@@ -33,7 +33,7 @@ char* strip(char* str) {
 
   // Allocate a slot for all the "saved" characters
   // plus one extra for the null terminator.
-  char* result = calloc(size-num_spaces+1, sizeof(char));
+  char* result = (char*) calloc(size-num_spaces+1, sizeof(char));
 
   // Copy in the "saved" characters.
   int i;
@@ -50,10 +50,10 @@ char* strip(char* str) {
  * Return true (1) if the given string is "clean", i.e., has
  * no spaces at the front or the back of the string.
  */
-int is_clean(char* str) {
+int is_clean(char const *str) {
   // We check if it's clean by calling strip and seeing if the
   // result is the same as the original string.
-  char* cleaned = strip(str);
+  char const *cleaned = strip(str);
 
   // strcmp compares two strings, returning a negative value if
   // the first is less than the second (in alphabetical order),
@@ -63,27 +63,3 @@ int is_clean(char* str) {
 
   return result == 0;
 }
-
-int main() {
-  int NUM_STRINGS = 7;
-  // Makes an array of 7 string constants for testing.
-  char* strings[] = {
-    "Morris",
-    "  stuff",
-    "Minnesota",
-    "nonsense  ",
-    "USA",
-    "   ",
-    "     silliness    "
-  };
-
-  for (int i = 0; i < NUM_STRINGS; ++i) {
-    if (is_clean(strings[i])) {
-      printf("The string '%s' is clean.\n", strings[i]);
-    } else {
-      printf("The string '%s' is NOT clean.\n", strings[i]);
-    }
-  }
-
-  return 0;
-}

check_whitespace.h

@@ -0,0 +1,7 @@
+#ifndef CHECK_WHITESPACE_H_GUARD
+#define CHECK_WHITESPACE_H_GUARD
+
+char* strip(char const *str);
+int is_clean(char const *str);
+
+#endif

check_whitespace_test.cpp

@@ -0,0 +1,48 @@
+#include <gtest/gtest.h>
+
+#include "check_whitespace.h"
+
+TEST(Strip, EmptyString) {
+    ASSERT_STREQ("", strip(""));
+}
+
+TEST(Strip, NoWhitespace) {
+    ASSERT_STREQ("frog", strip("frog"));
+}
+
+TEST(Strip, WhitespaceOnFront) {
+    ASSERT_STREQ("frog", strip("   frog"));
+}
+
+TEST(Strip, WhitespaceOnBack) {
+    ASSERT_STREQ("frog", strip("frog  "));
+}
+
+TEST(Strip, WhitespaceOnBothEnds) {
+    ASSERT_STREQ("frog", strip("  frog     "));
+}
+
+TEST(IsClean, EmptyString) {
+    ASSERT_TRUE(is_clean(""));
+}
+
+TEST(IsClean, NoWhitespace) {
+    ASSERT_TRUE(is_clean("University of Minnesota Morris"));
+}
+
+TEST(IsClean, WhitespaceOnFront) {
+    ASSERT_FALSE(is_clean("   University of Minnesota Morris"));
+}
+
+TEST(IsClean, WhitespaceOnBack) {
+    ASSERT_FALSE(is_clean("University of Minnesota Morris  "));
+}
+
+TEST(IsClean, WhitespaceOnBothEnds) {
+    ASSERT_FALSE(is_clean(" University of Minnesota Morris"    ));
+}
+
+int main(int argc, char *argv[]) {
+  ::testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}

main.c

@@ -0,0 +1,27 @@
+#include <stdio.h>
+
+#include "check_whitespace.h"
+
+int main() {
+  int NUM_STRINGS = 7;
+  // Makes an array of 7 string constants for testing.
+  char const *strings[] = {
+    "Morris",
+    "  stuff",
+    "Minnesota",
+    "nonsense  ",
+    "USA",
+    "   ",
+    "     silliness    "
+  };
+
+  for (int i = 0; i < NUM_STRINGS; ++i) {
+    if (is_clean(strings[i])) {
+      printf("The string '%s' is clean.\n", strings[i]);
+    } else {
+      printf("The string '%s' is NOT clean.\n", strings[i]);
+    }
+  }
+
+  return 0;
+}