Add tests for SplitString

Author: psx95

api/test/trace/propagation/detail/string_test.cc

@@ -2,12 +2,57 @@
 // SPDX-License-Identifier: Apache-2.0
 
 #include <gtest/gtest.h>
-#include <stdint.h>
+#include <opentelemetry/trace/propagation/b3_propagator.h>
 #include <string>
 
 #include "opentelemetry/nostd/string_view.h"
 
-TEST(StringTest, SplitString)
+struct SplitStringTestData
 {
-  // TODO(psx95): Add tests
-}
+  opentelemetry::nostd::string_view input;
+  char separator;
+  size_t max_count;
+  std::vector<opentelemetry::nostd::string_view> splits;
+  size_t expected_number_strings;
+};
+
+const SplitStringTestData split_string_test_cases[] = {
+    {"foo,bar,baz", ',', 4,
+    std::vector<opentelemetry::nostd::string_view>{"foo", "bar", "baz"}, 3},
+    {"foo,bar,baz,foobar", ',', 4,
+     std::vector<opentelemetry::nostd::string_view>{"foo", "bar", "baz", "foobar"}, 4},
+    {"foo,bar,baz,foobar", '.', 4,
+     std::vector<opentelemetry::nostd::string_view>{"foo,bar,baz,foobar"}, 1},
+    {"foo,bar,baz,", ',', 4,
+     std::vector<opentelemetry::nostd::string_view>{"foo","bar","baz",""}, 4},
+    {"foo,bar,baz,", ',', 2,
+     std::vector<opentelemetry::nostd::string_view>{"foo","bar"}, 2},
+    {"foo ,bar, baz ", ',', 4,
+     std::vector<opentelemetry::nostd::string_view>{"foo ","bar"," baz "}, 3},
+    {"foo ,bar, baz ", ',', 4,
+     std::vector<opentelemetry::nostd::string_view>{"foo ","bar"," baz "}, 3},
+    {"00-0af7651916cd43dd8448eb211c80319c-00f067aa0ba902b7-01", '-', 4,
+     std::vector<opentelemetry::nostd::string_view>{"00","0af7651916cd43dd8448eb211c80319c","00f067aa0ba902b7", "01"}, 4},
+};
+
+// Test fixture
+class SplitStringTestFixture : public ::testing::TestWithParam<SplitStringTestData> {};
+
+TEST_P(SplitStringTestFixture, SplitsAsExpected)
+{
+  SplitStringTestData test_param = GetParam();
+  std::vector<opentelemetry::nostd::string_view> fields{};
+  fields.reserve(test_param.expected_number_strings);
+  size_t got_splits_num =  opentelemetry::trace::propagation::detail::SplitString(test_param.input, test_param.separator, fields.data(), test_param.max_count);
+
+
+  // Assert on the output
+  EXPECT_EQ(got_splits_num, test_param.expected_number_strings);
+  for (size_t i = 0; i < got_splits_num; i++)
+  {
+    // Checks for resulting strings in-order
+    EXPECT_EQ(fields[i], test_param.splits[i]);
+  }
+}
+
+INSTANTIATE_TEST_SUITE_P(SplitStringTestCases, SplitStringTestFixture, ::testing::ValuesIn(split_string_test_cases));