Merge topic 'string-prefix'

ec7928ef26 use _s to construct static string_views at several places
94de927cab VS10Generator: avoid many string allocations
8ca2504a4d use string_views to avoid memory allocations
761f1adcae check for a valid URL scheme before starting to do any splitting
ef778d77e0 replace std::string::substr() with operations that do not allocate memory
77616f4681 pass cm::string_view to cmVisualStudioSlnParser::ParseTag()
ada6a3226f use cm::string_view for language extension lookups
48adc29721 replace "std::string::find(x) == 0" with cmHasPrefix()
...

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !4501

7 files changed, 30 insertions, 35 deletions

diff --git a/Source/CPack/IFW/cmCPackIFWGenerator.cxx b/Source/CPack/IFW/cmCPackIFWGenerator.cxx
index 509ac65..2806c61 100644
--- a/Source/CPack/IFW/cmCPackIFWGenerator.cxx
+++ b/Source/CPack/IFW/cmCPackIFWGenerator.cxx
@@ -544,10 +544,7 @@ std::string cmCPackIFWGenerator::GetGroupPackageName(
   if (group->ParentGroup) {
     cmCPackIFWPackage* package = this->GetGroupPackage(group->ParentGroup);
     bool dot = !this->ResolveDuplicateNames;
-    if (dot && name.substr(0, package->Name.size()) == package->Name) {
-      dot = false;
-    }
-    if (dot) {
+    if (dot && !cmHasPrefix(name, package->Name)) {
       name = package->Name + "." + name;
     }
   }
@@ -576,10 +573,7 @@ std::string cmCPackIFWGenerator::GetComponentPackageName(
       return package->Name;
     }
     bool dot = !this->ResolveDuplicateNames;
-    if (dot && name.substr(0, package->Name.size()) == package->Name) {
-      dot = false;
-    }
-    if (dot) {
+    if (dot && !cmHasPrefix(name, package->Name)) {
       name = package->Name + "." + name;
     }
   }
diff --git a/Source/CPack/IFW/cmCPackIFWPackage.cxx b/Source/CPack/IFW/cmCPackIFWPackage.cxx
index 9a9cd56..56a74c5 100644
--- a/Source/CPack/IFW/cmCPackIFWPackage.cxx
+++ b/Source/CPack/IFW/cmCPackIFWPackage.cxx
@@ -55,8 +55,7 @@ cmCPackIFWPackage::DependenceStruct::DependenceStruct(
   if (dashPos != std::string::npos) {
     pos = dashPos;
   }
-  this->Name =
-    pos == std::string::npos ? dependence : dependence.substr(0, pos);
+  this->Name = dependence.substr(0, pos);
 }
 
 std::string cmCPackIFWPackage::DependenceStruct::NameWithCompare() const
diff --git a/Source/CPack/WiX/cmCPackWIXGenerator.cxx b/Source/CPack/WiX/cmCPackWIXGenerator.cxx
index 67d3d32..e481d13 100644
--- a/Source/CPack/WiX/cmCPackWIXGenerator.cxx
+++ b/Source/CPack/WiX/cmCPackWIXGenerator.cxx
@@ -98,7 +98,7 @@ bool cmCPackWIXGenerator::RunCandleCommand(std::string const& sourceFile,
     command << " -ext " << QuotePath(ext);
   }
 
-  if (sourceFile.rfind(this->CPackTopLevel, 0) != 0) {
+  if (!cmHasSuffix(sourceFile, this->CPackTopLevel)) {
     command << " " << QuotePath("-I" + this->CPackTopLevel);
   }
 
@@ -350,8 +350,7 @@ void cmCPackWIXGenerator::CreateWiXPropertiesIncludeFile()
   std::vector<std::string> options = GetOptions();
 
   for (std::string const& name : options) {
-    if (name.length() > prefix.length() &&
-        name.substr(0, prefix.length()) == prefix) {
+    if (cmHasPrefix(name, prefix)) {
       std::string id = name.substr(prefix.length());
       std::string value = GetOption(name.c_str());
 
@@ -1099,14 +1098,14 @@ std::string cmCPackWIXGenerator::CreateHashedId(
   cmCryptoHash sha1(cmCryptoHash::AlgoSHA1);
   std::string const hash = sha1.HashString(path);
 
-  std::string identifier = cmStrCat(cm::string_view(hash).substr(0, 7), '_');
-
   const size_t maxFileNameLength = 52;
+  std::string identifier =
+    cmStrCat(cm::string_view(hash).substr(0, 7), '_',
+             cm::string_view(normalizedFilename).substr(0, maxFileNameLength));
+
+  // if the name was truncated
   if (normalizedFilename.length() > maxFileNameLength) {
-    identifier += normalizedFilename.substr(0, maxFileNameLength - 3);
     identifier += "...";
-  } else {
-    identifier += normalizedFilename;
   }
 
   return identifier;
diff --git a/Source/CPack/WiX/cmWIXAccessControlList.cxx b/Source/CPack/WiX/cmWIXAccessControlList.cxx
index 3668b46..9685a7f 100644
--- a/Source/CPack/WiX/cmWIXAccessControlList.cxx
+++ b/Source/CPack/WiX/cmWIXAccessControlList.cxx
@@ -2,6 +2,8 @@
    file Copyright.txt or https://cmake.org/licensing for details.  */
 #include "cmWIXAccessControlList.h"
 
+#include <cm/string_view>
+
 #include "cmCPackGenerator.h"
 #include "cmStringAlgorithms.h"
 #include "cmSystemTools.h"
@@ -35,12 +37,13 @@ void cmWIXAccessControlList::CreatePermissionElement(std::string const& entry)
     return;
   }
 
-  std::string user_and_domain = entry.substr(0, pos);
-  std::string permission_string = entry.substr(pos + 1);
+  cm::string_view enview(entry);
+  cm::string_view user_and_domain = enview.substr(0, pos);
+  cm::string_view permission_string = enview.substr(pos + 1);
 
   pos = user_and_domain.find('@');
-  std::string user;
-  std::string domain;
+  cm::string_view user;
+  cm::string_view domain;
   if (pos != std::string::npos) {
     user = user_and_domain.substr(0, pos);
     domain = user_and_domain.substr(pos + 1);
@@ -51,9 +54,9 @@ void cmWIXAccessControlList::CreatePermissionElement(std::string const& entry)
   std::vector<std::string> permissions = cmTokenize(permission_string, ",");
 
   this->SourceWriter.BeginElement("Permission");
-  this->SourceWriter.AddAttribute("User", user);
+  this->SourceWriter.AddAttribute("User", std::string(user));
   if (!domain.empty()) {
-    this->SourceWriter.AddAttribute("Domain", domain);
+    this->SourceWriter.AddAttribute("Domain", std::string(domain));
   }
   for (std::string const& permission : permissions) {
     this->EmitBooleanAttribute(entry, cmTrimWhitespace(permission));
diff --git a/Source/CPack/cmCPackNSISGenerator.cxx b/Source/CPack/cmCPackNSISGenerator.cxx
index 363f536..6b30407 100644
--- a/Source/CPack/cmCPackNSISGenerator.cxx
+++ b/Source/CPack/cmCPackNSISGenerator.cxx
@@ -68,7 +68,7 @@ int cmCPackNSISGenerator::PackageFiles()
 
       // Use the custom component install directory if we have one
       if (pos != std::string::npos) {
-        const std::string componentName = fileN.substr(0, pos);
+        auto componentName = cm::string_view(fileN).substr(0, pos);
         outputDir = CustomComponentInstallDirectory(componentName);
       } else {
         outputDir = CustomComponentInstallDirectory(fileN);
@@ -103,7 +103,7 @@ int cmCPackNSISGenerator::PackageFiles()
         componentName = fileN.substr(0, slash);
 
         // Strip off the component part of the path.
-        fileN = fileN.substr(slash + 1);
+        fileN.erase(0, slash + 1);
       }
     }
     std::replace(fileN.begin(), fileN.end(), '/', '\\');
@@ -672,7 +672,7 @@ std::string cmCPackNSISGenerator::CreateComponentDescription(
 
   const std::string componentOutputDir =
     CustomComponentInstallDirectory(component->Name);
-  componentCode += "  SetOutPath \"" + componentOutputDir + "\"\n";
+  componentCode += cmStrCat("  SetOutPath \"", componentOutputDir, "\"\n");
 
   // Create the actual installation commands
   if (component->IsDownloaded) {
@@ -921,12 +921,11 @@ std::string cmCPackNSISGenerator::CreateComponentGroupDescription(
 }
 
 std::string cmCPackNSISGenerator::CustomComponentInstallDirectory(
-  const std::string& componentName)
+  cm::string_view componentName)
 {
-  const char* outputDir =
-    this->GetOption("CPACK_NSIS_" + componentName + "_INSTALL_DIRECTORY");
-  const std::string componentOutputDir = (outputDir ? outputDir : "$INSTDIR");
-  return componentOutputDir;
+  const char* outputDir = this->GetOption(
+    cmStrCat("CPACK_NSIS_", componentName, "_INSTALL_DIRECTORY"));
+  return outputDir ? outputDir : "$INSTDIR";
 }
 
 std::string cmCPackNSISGenerator::TranslateNewlines(std::string str)
diff --git a/Source/CPack/cmCPackNSISGenerator.h b/Source/CPack/cmCPackNSISGenerator.h
index 0af37af..88cba45 100644
--- a/Source/CPack/cmCPackNSISGenerator.h
+++ b/Source/CPack/cmCPackNSISGenerator.h
@@ -10,6 +10,8 @@
 #include <string>
 #include <vector>
 
+#include <cm/string_view>
+
 #include "cmCPackGenerator.h"
 
 class cmCPackComponent;
@@ -75,8 +77,7 @@ protected:
 
   /// Returns the custom install directory if available for the specified
   /// component, otherwise $INSTDIR is returned.
-  std::string CustomComponentInstallDirectory(
-    const std::string& componentName);
+  std::string CustomComponentInstallDirectory(cm::string_view componentName);
 
   /// Translations any newlines found in the string into \\r\\n, so that the
   /// resulting string can be used within NSIS.
diff --git a/Source/CPack/cpack.cxx b/Source/CPack/cpack.cxx
index dc31623..2e5bde2 100644
--- a/Source/CPack/cpack.cxx
+++ b/Source/CPack/cpack.cxx
@@ -85,7 +85,7 @@ int cpackDefinitionArgument(const char* argument, const char* cValue,
     return 0;
   }
   std::string key = value.substr(0, pos);
-  value = value.substr(pos + 1);
+  value.erase(0, pos + 1);
   def->Map[key] = value;
   cmCPack_Log(def->Log, cmCPackLog::LOG_DEBUG,
               "Set CPack variable: " << key << " to \"" << value << "\""