hiliteMatches(): Style fixes, pass more stuff by reference

1 files changed, 13 insertions, 5 deletions

diff --git a/src/libutil/fmt.cc b/src/libutil/fmt.cc
index 914fb62b2..3dd93d73e 100644
--- a/src/libutil/fmt.cc
+++ b/src/libutil/fmt.cc
@@ -1,13 +1,20 @@
+#include "fmt.hh"
+
 #include <regex>
 
 namespace nix {
 
-std::string hiliteMatches(const std::string &s, std::vector<std::smatch> matches, std::string prefix, std::string postfix) {
+std::string hiliteMatches(
+    std::string_view s,
+    std::vector<std::smatch> matches,
+    std::string_view prefix,
+    std::string_view postfix)
+{
     // Avoid copy on zero matches
     if (matches.size() == 0)
-        return s;
+        return (std::string) s;
 
-    std::sort(matches.begin(), matches.end(), [](const auto &a, const auto &b) {
+    std::sort(matches.begin(), matches.end(), [](const auto & a, const auto & b) {
         return a.position() < b.position();
     });
 
@@ -20,10 +27,10 @@ std::string hiliteMatches(const std::string &s, std::vector<std::smatch> matches
         out.append(s.substr(last_end, m.position() - last_end));
         // Merge continous matches
         ssize_t end = start + m.length();
-        while(++it != matches.end() && (*it).position() <= end) {
+        while (++it != matches.end() && (*it).position() <= end) {
             auto n = *it;
             ssize_t nend = start + (n.position() - start + n.length());
-            if(nend > end)
+            if (nend > end)
                 end = nend;
         }
         out.append(prefix);
@@ -31,6 +38,7 @@ std::string hiliteMatches(const std::string &s, std::vector<std::smatch> matches
         out.append(postfix);
         last_end = end;
     }
+
     out.append(s.substr(last_end));
     return out;
 }