MakeNotNull is similar to UniquePtr, in that it combines the infallible
allocation and construction of an object on the heap and wraps the (raw or
smart) pointer into a NotNull.
It skips the unnecessary null check from WrapNotNull, and removes the usual
naked 'new' used in many WrapNotNull calls.
MozReview-Commit-ID: UwCrhDnkUg
--HG--
extra : rebase_source : 5a027165fc17ed748783c7ffda03eb421865ad6e
Delete Span's implicit constructors for char* and char16_t* pointers to avoid accidental construction in cases where a pointer does not point to a zero-terminated string. Use the MakeStringSpan() function instead.
I deleted both the const and non-const char* and char16_t* constructors, in the name of cross-compiler consistency. If we only delete the const char* and char16_t* constructors, for some reason, MSVC complains that `Span<char> s(charArray)` uses a deleted constructor while clang nor gcc permit it. I don't know if this is a compiler bug in MSVC or clang and gcc.
Also, do not permit MakeSpan() for string literals (const char and char16_t arrays) because the Span length would include the zero terminator, which may surprise callers. Use MakeStringSpan() to create a Span whose length that excludes the string literal's zero terminator or use the MakeSpan() overload that accepts a pointer and length and specify the string literal's full length.
The following Span usages are prevented:
Span<const char> span("literal"); // error
Span<char> span(charArray); // error
Span<const char> span;
span = "literal"; // error
span = charArray; // error
MakeSpan("literal"); // error
The following Span usages are still permitted:
assert(MakeStringSpan("literal") == 8); // OK: span length is calculated with strlen() and excludes the zero terminator
MakeStringSpan(charArray); // OK: span length is calculated with strlen() and excludes the zero terminator
MakeSpan(charArray); // OK: span length is the char array size including any zero terminator
MozReview-Commit-ID: Et71CpjsiyI
--HG--
extra : rebase_source : f6f8bdb28726f0f2368fdfdd039fb1d7dcf2914e
extra : source : 0547d8924ffc7713d6cf32cc06eeeaf00e0d69a3
While the flexibility of the current trait is nice, it's actually not
used to its fullest anywhere, and is boilerplate-y. While it is useful
to be able to put the links anywhere, there's not much usefulness from
being able to split mNext and mPrev.
So instead of a trait that allows to get/set mNext and mPrev
independently, we just use a trait that tells how to get a reference to
a DoublyLinkedListElement from a list element itself.
--HG--
extra : rebase_source : 674277bac4fc979f2e483a77b5ef1495baccc7fe
While the flexibility of the current trait is nice, it's actually not
used to its fullest anywhere, and is boilerplate-y. While it is useful
to be able to put the links anywhere, there's not much usefulness from
being able to split mNext and mPrev.
So instead of a trait that allows to get/set mNext and mPrev
independently, we just use a trait that tells how to get a reference to
a DoublyLinkedListElement from a list element itself.
--HG--
extra : rebase_source : f84c5799c305a4a3b7dc5deb727a05d4d537bb15
While the flexibility of the current trait is nice, it's actually not
used to its fullest anywhere, and is boilerplate-y. While it is useful
to be able to put the links anywhere, there's not much usefulness from
being able to split mNext and mPrev.
So instead of a trait that allows to get/set mNext and mPrev
independently, we just use a trait that tells how to get a reference to
a DoublyLinkedListElement from a list element itself.
--HG--
extra : rebase_source : b7d502754a764670e291acdd56726948db935497
The macro simultaneously declares an enumeration and a count of its
enumerators.
A few variants of the macro are also provided to handle things like
enum classes, underlying types, and enumerations declared at class
scope.
MozReview-Commit-ID: 3z6yHnfXbLj
--HG--
extra : rebase_source : 92c333693e4bbf85b89cd3d7ac5b31f4b5434367
mfbt/tests/TestDoublyLinkedList.cpp:138:24 [-Wunused-member-function] unused member function 'GetPrev'
MozReview-Commit-ID: HQuTw0vXRKV
--HG--
extra : source : 0db3bd8a40d67a81b2f224dc9e63012cb832d0b9
extra : intermediate-source : 948c43ff15b4ca1a3db335544494562ec28e67cc
I'm not sure how I tested MOZ_FOR_EACH in bug 1368932, but it turns out
it doesn't work with an empty list, despite
MOZ_PASTE_PREFIX_AND_ARG_COUNT now supporting 0 arguments.
Macros can be tricky, and it ends up being easier to make things work
cross-compiler with a separate macro that does the counting, and
(re)building MOZ_PASTE_PREFIX_AND_ARG_COUNT on top of that. Then
MOZ_FOR_EACH ends up working as expected with an empty list.
So this adds a MOZ_ARG_COUNT macro that counts the number of variadic
arguments it's given, and derives MOZ_PASTE_PREFIX_AND_ARG_COUNT from
it.
And this adds a testcase validating that MOZ_FOR_EACH works properly
with an empty list as a result.
--HG--
extra : rebase_source : 309371d87bd1561fbd2153f44fc1256185045d23
At the same time, remove the MOZ_STATIC_ASSERT_VALID_ARG_COUNT, which
doesn't actually work for more than 50 arguments(*), and which is now not
useful to detect 0 arguments.
(*) the build fails, but not directly thanks to the static_assert it
expands to.
--HG--
extra : rebase_source : 8f0fe7b352c89b5a3ec87f42ef5464c370c362ef
