[clang-tools-extra] [clang-tidy] fix `bugprone-narrowing-conversions` false positive for conditional expression (PR #139474)

[via cfe-commits]

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@@ -0,0 +1,22 @@
+// RUN: %check_clang_tidy %s bugprone-narrowing-conversions %t -- --
+
+char test_char(int cond, char c) {
+	char ret = cond > 0 ? ':' : c;
+	return ret;
+}
+
+short test_short(int cond, short s) {
+	short ret = cond > 0 ? ':' : s;
+	return ret;
+}
+
+int test_int(int cond, int i) {
+	int ret = cond > 0 ? ':' : i;
+	return ret;
+}
+
+void test(int cond, int i) {
+  char x = cond > 0 ? ':' : i;
+  // CHECK-MESSAGES: :[[@LINE-1]]:29: warning: narrowing conversion from 'int' to signed type 'char' is implementation-defined [bugprone-narrowing-conversions]
+}
+
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EugeneZelenko wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/139474