cleanup and formatting

ortools/base/dump_vars.h

@@ -142,7 +142,8 @@ std::ostream& operator<<(std::ostream& os, const ::std::optional<T>& opt) {
 
 // needed by graph tests
 template <typename T, typename U>
-std::ostream& operator<<(std::ostream& os, const ::util_intops::StrongVector<T, U>& vec) {
+std::ostream& operator<<(std::ostream& os,
+                         const ::util_intops::StrongVector<T, U>& vec) {
   for (U it : vec) {
     os << ::std::to_string(it) << ',';
   }

ortools/base/dump_vars_test.cc

@@ -137,7 +137,8 @@ TEST(DumpVars, StrongInt) {
 }
 
 TEST(DumpVars, StrongVector) {
-  ::util_intops::StrongVector<::util_intops::CustomStrongInt, float> vec = {49.3, 3.14};
+  ::util_intops::StrongVector<::util_intops::CustomStrongInt, float> vec = {
+      49.3, 3.14};
   EXPECT_EQ(R"(vec = 49.299999,3.140000,)", ToString(DUMP_VARS(vec)));
   EXPECT_EQ(R"(vec = 49.299999,3.140000,)", DUMP_VARS(vec).str());
 }

ortools/linear_solver/model_exporter.cc

@@ -57,7 +57,7 @@ class LineBreaker {
 
   // Returns true if string s will fit on the current line without adding a
   // carriage return.
-  bool WillFit(const std::string& s) {
+  bool WillFit(absl::string_view s) {
     return line_size_ + static_cast<int>(s.size()) < max_line_size_;
   }
 

ortools/linear_solver/xpress_interface.cc

@@ -20,8 +20,8 @@
 #include <limits>
 #include <memory>
 #include <mutex>
-#include <string>
 #include <numeric>
+#include <string>
 
 #include "absl/strings/numbers.h"
 #include "absl/strings/str_format.h"
@@ -1094,7 +1094,8 @@ void XpressInterface::SetCoefficient(MPConstraint* const constraint,
                                      double new_value, double) {
   InvalidateSolutionSynchronization();
 
-  fixedOrderCoefficientsPerConstraint[constraint->index()][variable->index()] = new_value;
+  fixedOrderCoefficientsPerConstraint[constraint->index()][variable->index()] =
+      new_value;
 
   // Changing a single coefficient in the matrix is potentially pretty
   // slow since that coefficient has to be found in the sparse matrix

ortools/math_opt/io/proto_converter.cc

@@ -317,7 +317,7 @@ MPModelProtoToMathOptModel(const ::operations_research::MPModelProto& model) {
 
   for (const MPGeneralConstraintProto& general_constraint :
        model.general_constraint()) {
-    const std::string& in_name = general_constraint.name();
+    absl::string_view in_name = general_constraint.name();
     switch (general_constraint.general_constraint_case()) {
       case MPGeneralConstraintProto::kQuadraticConstraint: {
         (*output.mutable_quadratic_constraints())