Handle trailing underscores on modernize-loop-convert variable namer.

[angelgarcia]

Summary

https://llvm.org/bugs/show_bug.cgi?id=24961.

[klimek]

clang-tidy/modernize/LoopConvertUtils.cpp

822

Do you mean: E.g.?

[angelgarcia]

Yes! Sorry.

[angelgarcia]

I forgot one.

[klimek]

lg

clang-tidy/modernize/LoopConvertUtils.cpp

std::string VariableNamer::createIndexName() {
   std::string IteratorName;
   StringRef ContainerName;
   if (TheContainer)
     ContainerName = TheContainer->getName();
 
   size_t Len = ContainerName.size();
   if (Len > 1 && ContainerName.endswith(Style == NS_UpperCase ? "S" : "s")) {
     IteratorName = ContainerName.substr(0, Len - 1);
+    // Ej: (auto thing : things)
+    if (!declarationExists(IteratorName))
+      return IteratorName;
+  }
+
+  if (Len > 2 && ContainerName.endswith(Style == NS_UpperCase ? "S_" : "s_")) {
+    IteratorName = ContainerName.substr(0, Len - 2);
+    // E.g.: (auto thing : things_)
     if (!declarationExists(IteratorName))
       return IteratorName;
   }
 
   std::string Elem;
   switch (Style) {
   case NS_CamelBack:
   case NS_LowerCase:
     Elem = "elem";
     break;
   case NS_CamelCase:
     Elem = "Elem";
     break;
   case NS_UpperCase:
     Elem = "ELEM";
   }
+  // E.g.: (auto elem : container)
   if (!declarationExists(Elem))
     return Elem;
 
   IteratorName = AppendWithStyle(ContainerName, OldIndex->getName());
+  // E.g.: (auto container_i : container)
   if (!declarationExists(IteratorName))
     return IteratorName;
 
   IteratorName = AppendWithStyle(ContainerName, Elem);
+  // E.g.: (auto container_elem : container)
   if (!declarationExists(IteratorName))
     return IteratorName;
 
   // Someone defeated my naming scheme...
   std::string GiveMeName;
   switch (Style) {
   case NS_CamelBack:
     GiveMeName = "giveMeName";

test/clang-tidy/modernize-loop-convert-lowercase.cpp

 // RUN: %python %S/check_clang_tidy.py %s modernize-loop-convert %t \
 // RUN:   -config="{CheckOptions: [{key: modernize-loop-convert.NamingStyle, value: 'lower_case'}]}" \
 // RUN:   -- -std=c++11 -I %S/Inputs/modernize-loop-convert
 
 #include "structures.h"
 
 const int n = 10;
 int arr[n];
 int nums[n];
+int nums_[n];
 
 void naming() {
   for (int i = 0; i < n; ++i) {
     printf("%d\n", arr[i]);
   }
   // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use range-based for loop instead [modernize-loop-convert]
   // CHECK-FIXES: for (auto & elem : arr)
   // CHECK-FIXES-NEXT: printf("%d\n", elem);
 
   for (int i = 0; i < n; ++i) {
     printf("%d\n", nums[i]);
   }
   // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use range-based for loop instead
   // CHECK-FIXES: for (auto & num : nums)
   // CHECK-FIXES-NEXT: printf("%d\n", num);
 
+  for (int i = 0; i < n; ++i) {
+    printf("%d\n", nums_[i]);
+  }
+  // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use range-based for loop instead
+  // CHECK-FIXES: for (auto & num : nums_)
+  // CHECK-FIXES-NEXT: printf("%d\n", num);
+
   int num = 0;
   for (int i = 0; i < n; ++i) {
     printf("%d\n", nums[i] + num);
   }
   // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use range-based for loop instead
   // CHECK-FIXES: for (auto & elem : nums)
   // CHECK-FIXES-NEXT: printf("%d\n", elem + num);
 

test/clang-tidy/modernize-loop-convert-uppercase.cpp

 // RUN: %python %S/check_clang_tidy.py %s modernize-loop-convert %t \
 // RUN:   -config="{CheckOptions: [{key: modernize-loop-convert.NamingStyle, value: 'UPPER_CASE'}]}" \
 // RUN:   -- -std=c++11 -I %S/Inputs/modernize-loop-convert
 
 #include "structures.h"
 
 const int N = 10;
 int ARR[N];
 int NUMS[N];
+int NUMS_[N];
 
 void naming() {
   for (int I = 0; I < N; ++I) {
     printf("%d\n", ARR[I]);
   }
   // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use range-based for loop instead [modernize-loop-convert]
   // CHECK-FIXES: for (auto & ELEM : ARR)
   // CHECK-FIXES-NEXT: printf("%d\n", ELEM);
 
   for (int I = 0; I < N; ++I) {
     printf("%d\n", NUMS[I]);
   }
   // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use range-based for loop instead
   // CHECK-FIXES: for (auto & NUM : NUMS)
   // CHECK-FIXES-NEXT: printf("%d\n", NUM);
 
+  for (int I = 0; I < N; ++I) {
+    printf("%d\n", NUMS_[I]);
+  }
+  // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use range-based for loop instead
+  // CHECK-FIXES: for (auto & NUM : NUMS_)
+  // CHECK-FIXES-NEXT: printf("%d\n", NUM);
+
   int NUM = 0;
   for (int I = 0; I < N; ++I) {
     printf("%d\n", NUMS[I] + NUM);
   }
   // CHECK-MESSAGES: :[[@LINE-3]]:3: warning: use range-based for loop instead
   // CHECK-FIXES: for (auto & ELEM : NUMS)
   // CHECK-FIXES-NEXT: printf("%d\n", ELEM + NUM);