[clang-tidy][docs][NFC] Improve documentation of bugprone-unhandled-exception-at-new

[Eugene.Zelenko]

clang-tools-extra/docs/clang-tidy/checks/bugprone-unhandled-exception-at-new.rst

31

Two excessive newlines.

[whisperity]

clang-tools-extra/docs/clang-tidy/checks/bugprone-unhandled-exception-at-new.rst

8–10

by the code is either superfluous or misleading. Did you mean that the exception should be caught and handled in the same scope where the allocation took place?

16–17

19–20

What does

exception types or exceptions

mean?

26

Is that the warning message the check prints?

35

[balazske]

Apply of review comments.

[balazske]

clang-tools-extra/docs/clang-tidy/checks/bugprone-unhandled-exception-at-new.rst

19–20

Now it is probably better. "Other exception" is any thrown exception of other class than the mentioned ones.

26

Warning text is changed to the exact checker's message.

[aaron.ballman]

LGTM aside from a small nit.

clang-tools-extra/docs/clang-tidy/checks/bugprone-unhandled-exception-at-new.rst

16–17

[balazske]

Applied the text changes.

clang-tools-extra/docs/clang-tidy/checks/bugprone-unhandled-exception-at-new.rst

 .. title:: clang-tidy - bugprone-unhandled-exception-at-new
 
 bugprone-unhandled-exception-at-new
 ===================================
 
 Finds calls to ``new`` with missing exception handler for ``std::bad_alloc``.
 
-.. code-block:: c++
-
-  int *f() noexcept {
-    int *p = new int[1000];
-    // ...
-    return p;
-  }
-
 Calls to ``new`` can throw exceptions of type ``std::bad_alloc`` that should
 be handled by the code. Alternatively, the nonthrowing form of ``new`` can be
 used. The check verifies that the exception is handled in the function
-that calls ``new``, unless a nonthrowing version is used or the exception
-is allowed to propagate out of the function (exception handler is checked for
-types ``std::bad_alloc``, ``std::exception``, and catch-all handler).
+that calls ``new``.
+
+If a nonthrowing version is used or the exception is allowed to propagate out
+of the function no warning is generated.
+
+The exception handler is checked for types ``std::bad_alloc``,
+``std::exception``, and catch-all handler.
 The check assumes that any user-defined ``operator new`` is either
 ``noexcept`` or may throw an exception of type ``std::bad_alloc`` (or derived
 from it). Other exception types or exceptions occurring in the object's
 constructor are not taken into account.
+
+.. code-block:: c++
+
+  int *f() noexcept {
+    int *p = new int[1000]; // warning: exception handler is missing
+    // ...
+    return p;
+  }
+
+
+
+.. code-block:: c++
+
+  int *f1() { // no 'noexcept'
+    int *p = new int[1000]; // no warning: exception can be handled outside
+                            // of this function
+    // ...
+    return p;
+  }
+
+  int *f2() noexcept {
+    try {
+      int *p = new int[1000]; // no warning: exception is handled
+      // ...
+      return p;
+    } catch (std::bad_alloc &) {
+      // ...
+    }
+    // ...
+  }
+
+  int *f3() noexcept {
+    int *p = new (std::nothrow) int[1000]; // no warning: "nothrow" is used
+    // ...
+    return p;
+  }
+