Use string view when appropriate.

[trivialfis]

• Add tests for string utilities.

[Copilot]

Pull Request Overview

This PR enhances common string utilities by introducing std::string_view variants, refactors version parsing for CUDA utilities, updates memory logging, and adds corresponding tests.

• Add std::string_view overloads for Split, TrimFirst, and TrimLast and clean up includes in common.h
• Replace std::stoi with std::from_chars in cuda_dr_utils.cc for driver version parsing
• Use common::HumanMemUnit in quantile logging and bump copyright to 2025
• Add tests in test_common.cc covering both std::string and std::string_view for trim and split functions

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
tests/cpp/common/test_common.cc	Add includes for <string_view> and new tests for trim/split
src/common/quantile.cuh	Bump copyright year and update logging to use HumanMemUnit
src/common/cuda_dr_utils.cc	Swap std::stoi for std::from_chars in version parsing
src/common/common.h	Introduce string_view overloads for Split and Trim*

Comments suppressed due to low confidence (3)

tests/cpp/common/test_common.cc:25

• [nitpick] The test case name 'Trim' is ambiguous since it covers both TrimFirst and TrimLast for different types. Consider splitting into distinct tests (e.g., 'TrimFirst' and 'TrimLast') or renaming to better reflect the combined functionality.

TEST(Common, Trim) {

tests/cpp/common/test_common.cc:25

• The trim function tests don’t cover edge cases such as empty strings or inputs containing only whitespace. Add test scenarios for these edge cases for both std::string and std::string_view overloads.

TEST(Common, Trim) {

src/common/common.h:90

• [nitpick] Add a documentation comment above TrimLast to explain that it trims trailing whitespace and returns a std::string_view of the result.

[[nodiscard]] inline std::string_view TrimLast(std::string_view const &str) {

[hcho3]

Is it possible to replace xgboost::StringView with std::string_view, now that we are using C++17?

[trivialfis]

I did a trick with the custom string view and JSON #8332
Might need to port it to the STL one. Let's put it in the backlog for now.