8

tests/test_8.cpp

@@ -0,0 +1,87 @@
+// This file is generated by mkfile.py
+// Date: 2026-06-25
+
+#include <gtest/gtest.h>
+#include <solution/8.h>
+
+#include <climits>
+#include <string>
+#include <vector>
+
+class MyAtoiTest : public ::testing::Test
+{
+  protected:
+    void AssertMyAtoi(const std::string &input, int expected)
+    {
+        std::vector<char> buffer(input.begin(), input.end());
+        buffer.push_back('\0');
+
+        EXPECT_EQ(myAtoi(buffer.data()), expected);
+    }
+};
+
+TEST_F(MyAtoiTest, Example1)
+{
+    AssertMyAtoi("42", 42);
+}
+
+TEST_F(MyAtoiTest, Example2)
+{
+    AssertMyAtoi("   -42", -42);
+}
+
+TEST_F(MyAtoiTest, Example3)
+{
+    AssertMyAtoi("4193 with words", 4193);
+}
+
+TEST_F(MyAtoiTest, ReturnsZeroWhenStringStartsWithNonDigit)
+{
+    AssertMyAtoi("words and 987", 0);
+}
+
+TEST_F(MyAtoiTest, ReadsOptionalPlusSign)
+{
+    AssertMyAtoi("+1", 1);
+}
+
+TEST_F(MyAtoiTest, RejectsMultipleOrSeparatedSigns)
+{
+    AssertMyAtoi("+-12", 0);
+    AssertMyAtoi("-+12", 0);
+    AssertMyAtoi("   +  413", 0);
+}
+
+TEST_F(MyAtoiTest, StopsAtFirstNonDigitAfterReadingDigits)
+{
+    AssertMyAtoi("3.14159", 3);
+    AssertMyAtoi("00000-42a1234", 0);
+    AssertMyAtoi("  +0 123", 0);
+}
+
+TEST_F(MyAtoiTest, HandlesEmptyAndSignOnlyStrings)
+{
+    AssertMyAtoi("", 0);
+    AssertMyAtoi("   ", 0);
+    AssertMyAtoi("+", 0);
+    AssertMyAtoi("-", 0);
+}
+
+TEST_F(MyAtoiTest, ClampsPositiveOverflow)
+{
+    AssertMyAtoi("2147483647", INT_MAX);
+    AssertMyAtoi("2147483648", INT_MAX);
+    AssertMyAtoi("91283472332", INT_MAX);
+}
+
+TEST_F(MyAtoiTest, ClampsNegativeOverflow)
+{
+    AssertMyAtoi("-2147483648", INT_MIN);
+    AssertMyAtoi("-2147483649", INT_MIN);
+    AssertMyAtoi("-91283472332", INT_MIN);
+}
+
+TEST_F(MyAtoiTest, IgnoresLeadingZerosBeforeValidDigits)
+{
+    AssertMyAtoi("  0000000000012345678", 12345678);
+}