[clang-tools-extra] [clang-tidy] Add `modernize-use-uniform-initializer` check (PR #91124)

[Piotr Zegar via cfe-commits]

================
@@ -0,0 +1,174 @@
+// RUN: %check_clang_tidy -std=c++11 %s modernize-use-uniform-initializer %t
+
+int cinit_0 = 0;
+// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int cinit_0 {0};
+
+int cinit_1=0;
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int cinit_1{0};
+
+int callinit_0(0);
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int callinit_0{0};
+
+int callinit_1 ( 0 );
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int callinit_1 {0};
+
+int callinit_2 ( ((3 + 1 + 4) + 1 + 5) );
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int callinit_2 {((3 + 1 + 4) + 1 + 5)};
+
+int callinit_3((9-2)+(6+5));
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int callinit_3{(9-2)+(6+5)};
+
+int callinit_4 ((3 * 5 + (8 - 9) ));
+// CHECK-MESSAGES: :[[@LINE-1]]:16: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int callinit_4 {(3 * 5 + (8 - 9) )};
+
+int callinit_5((7 + (-9)));
+// CHECK-MESSAGES: :[[@LINE-1]]:15: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int callinit_5{(7 + (-9))};
+
+int mixed_0 = {0};
+// CHECK-MESSAGES: :[[@LINE-1]]:13: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int mixed_0 {0};
+
+int mixed_1={0};
+// CHECK-MESSAGES: :[[@LINE-1]]:12: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: int mixed_1{0};
+
+int noinit;
+
+int correct_0{0};
+
+int correct_1 {0};
+
+struct CInitList_0 {
+    CInitList_0() : x(0) {}
+    // CHECK-MESSAGES: :[[@LINE-1]]:22: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+    // CHECK-FIXES: CInitList_0() : x{0} {}
+
+    int x;
+};
+
+struct CInitList_1 {
+    CInitList_1():x(0) {}
+    // CHECK-MESSAGES: :[[@LINE-1]]:20: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+    // CHECK-FIXES: CInitList_1():x{0} {}
+
+    int x;
+};
+
+struct CInitList_2 {
+    CInitList_2() : x ( 0 ) {}
+    // CHECK-MESSAGES: :[[@LINE-1]]:23: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+    // CHECK-FIXES: CInitList_2() : x {0} {}
+
+    int x;
+};
+
+struct Correct_0 {
+    Correct_0() : x{0} {}
+
+    int x;
+};
+
+struct Correct_1 {
+    Correct_1():x{0} {}
+
+    int x;
+};
+
+struct InClassInitializers {
+    int cinit_0 = 0;
+    // CHECK-MESSAGES: :[[@LINE-1]]:17: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+    // CHECK-FIXES: int cinit_0 {0};
+
+    int cinit_1=0;
+    // CHECK-MESSAGES: :[[@LINE-1]]:16: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+    // CHECK-FIXES: int cinit_1{0};
+
+    int mixed_0 = {0};
+    // CHECK-MESSAGES: :[[@LINE-1]]:17: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+    // CHECK-FIXES: int mixed_0 {0};
+
+    int mixed_1={0};
+    // CHECK-MESSAGES: :[[@LINE-1]]:16: warning: Use uniform initializer instead of C-style initializer [modernize-use-uniform-initializer]
+    // CHECK-FIXES: int mixed_1{0};
+
+    int noinit;
+
+    int correct_0 {0};
+
+    int correct_1{0};
+};
+
+// Defaulted function arguments cannot use the uniform initializer
+void f(int x = 0) {}
+
+struct A {
+    A() = default;
+    A(int) {}
+    A(int, int) {}
+};
+
+A a_0;
+A a_1{};
+A a_2(); // This is not a variable declaration it is actually a function definition (most vexing parse)
+A a_3{21};
+A a_4{ 21 };
+A a_5(42);
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: A a_5{42};
+A a_6 ( 42 );
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: A a_6 {42};
+A a_7{0, 1};
+A a_8{ 0, 1 };
+A a_9(0, 1);
+// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: A a_9{0, 1};
+A a_10( 1, 0 );
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: A a_10{1, 0};
+A a_11(A(3));
+// CHECK-MESSAGES: :[[@LINE-1]]:7: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: A a_11{A(3)};
+A a_12 ( A(3) );
+// CHECK-MESSAGES: :[[@LINE-1]]:8: warning: Use uniform initializer instead of call-style initializer [modernize-use-uniform-initializer]
+// CHECK-FIXES: A a_12 {A(3)};
----------------
PiotrZSL wrote:

shouldn't this also change `A(3)` into `A{3}` ?

https://github.com/llvm/llvm-project/pull/91124