Fix comparison of forward-declared and fully visible types

third_party/ocmock/OCMock/OCMBoxedReturnValueProvider.mm

-//---------------------------------------------------------------------------------------
-//  $Id$
-//  Copyright (c) 2009 by Mulle Kybernetik. See License file for details.
-//---------------------------------------------------------------------------------------
-
-#import "OCMBoxedReturnValueProvider.h"
-#import <objc/runtime.h>
-
-#if defined(__clang__)
-#include <vector>  // for _LIBCPP_ABI_VERSION to detect if using libc++
-#endif
-
-#if defined(__clang__) && defined(_LIBCPP_ABI_VERSION)
-namespace {
-// Default stack size to use when checking for matching opening and closing
-// characters (<> and {}). This is used to reduce the number of allocations
-// in AdvanceTypeDescriptionPointer function.
-const size_t kDefaultStackSize = 32;
-
-// Move to the next pertinent character in a type description. This skips
-// all the field expansion that clang includes in the type description when
-// compiling with libc++.
-//
-// See inner comment of -isValueTypeCompatibleWithInvocation: for more details.
-// Returns true if the pointer was advanced, false if the type description was
-// not correctly parsed.
-bool AdvanceTypeDescriptionPointer(const char *&typeDescription) {
-        if (!*typeDescription)
-                return true;
-
-        ++typeDescription;
-        if (*typeDescription != '=')
-                return true;
-
-        ++typeDescription;
-        std::vector<char> stack;
-        stack.reserve(kDefaultStackSize);
-        while (*typeDescription) {
-                const char current = *typeDescription;
-                if (current == '<' || current == '{') {
-                        stack.push_back(current);
-                } else if (current == '>' || current == '}') {
-                        if (!stack.empty()) {
-                                const char opening = stack.back();
-                                if ((opening == '<' && current != '>') ||
-                                                (opening == '{' && current != '}')) {
-                                        return false;
-                                }
-                                stack.pop_back();
-                        } else {
-                                return current == '}';
-                        }
-                } else if (current == ',' && stack.empty()) {
-                        return true;
-                }
-                ++typeDescription;
-        }
-        return true;
-}
-}
-#endif  // defined(__clang__) && defined(_LIBCPP_ABI_VERSION)
-
-@interface OCMBoxedReturnValueProvider ()
-
-- (BOOL)isValueTypeCompatibleWithInvocation:(NSInvocation *)anInvocation;
-
-@end
-
-@implementation OCMBoxedReturnValueProvider
-
-- (BOOL)isValueTypeCompatibleWithInvocation:(NSInvocation *)anInvocation {
-        const char *returnType = [[anInvocation methodSignature] methodReturnType];
-        const char *valueType = [(NSValue *)returnValue objCType];
-
-#if defined(__aarch64__) || defined(__x86_64__)
-        // ARM64 uses 'B' for BOOLs in method signature but 'c' in NSValue. That case
-        // should match.
-        if (strcmp(returnType, "B") == 0 && strcmp(valueType, "c") == 0)
-                return YES;
-#endif  // defined(__aarch64__) || defined(__x86_64__)
-
-#if defined(__clang__) && defined(_LIBCPP_ABI_VERSION)
-        // The type representation of the return type of the invocation, and the
-        // type representation passed to NSValue are not the same for C++ objects
-        // when compiling with libc++ with clang.
-        //
-        // In that configuration, the C++ class are expanded to list the types of
-        // the fields, but the depth of the expansion for templated types is larger
-        // for the value stored in the NSValue.
-        //
-        // For example, when creating a OCMOCK_VALUE with a GURL object (from the
-        // Chromium project), then the two types representations are:
-        //
-        // r^{GURL={basic_string<char, std::__1::char_traits<char>, std::__1::alloca
-        // tor<char> >={__compressed_pair<std::__1::basic_string<char, std::__1::cha
-        // r_traits<char>, std::__1::allocator<char> >::__rep, std::__1::allocator<c
-        // har> >={__rep}}}B{Parsed={Component=ii}{Component=ii}{Component=ii}{Compo
-        // nent=ii}{Component=ii}{Component=ii}{Component=ii}{Component=ii}^{Parsed}
-        // }{scoped_ptr<GURL, base::DefaultDeleter<GURL> >={scoped_ptr_impl<GURL, ba
-        // se::DefaultDeleter<GURL> >={Data=^{GURL}}}}}
-        //
-        // r^{GURL={basic_string<char, std::__1::char_traits<char>, std::__1::alloca
-        // tor<char> >={__compressed_pair<std::__1::basic_string<char, std::__1::cha
-        // r_traits<char>, std::__1::allocator<char> >::__rep, std::__1::allocator<c
-        // har> >={__rep=(?={__long=II*}{__short=(?=Cc)[11c]}{__raw=[3L]})}}}B{Parse
-        // d={Component=ii}{Component=ii}{Component=ii}{Component=ii}{Component=ii}{
-        // Component=ii}{Component=ii}{Component=ii}^{Parsed}}{scoped_ptr<GURL, base
-        // ::DefaultDeleter<GURL> >={scoped_ptr_impl<GURL, base::DefaultDeleter<GURL
-        // > >={Data=^{GURL}}}}}
-        //
-        // Since those types should be considered equals, we un-expand them during
-        // the comparison. For that, we remove everything following an "=" until we
-        // meet a non-matched "}" or a ",".
-
-        while (*returnType && *valueType) {
-                if (*returnType != *valueType)
-                        return NO;
-
-                if (!AdvanceTypeDescriptionPointer(returnType))
-                        return NO;
-
-                if (!AdvanceTypeDescriptionPointer(valueType))
-                        return NO;
-        }
-
-        return !*returnType && !*valueType;
-#else
-        return strcmp(returnType, valueType) == 0;
-#endif  // defined(__clang__) && defined(_LIBCPP_ABI_VERSION)
-}
-
-- (void)handleInvocation:(NSInvocation *)anInvocation
-{
-        if (![self isValueTypeCompatibleWithInvocation:anInvocation]) {
-                const char *returnType = [[anInvocation methodSignature] methodReturnType];
-                const char *valueType = [(NSValue *)returnValue objCType];
-                @throw [NSException exceptionWithName:NSInvalidArgumentException reason:[NSString stringWithFormat:@"Return value does not match method signature; signature declares '%s' but value is '%s'.", returnType, valueType] userInfo:nil];
-        }
-        void *buffer = malloc([[anInvocation methodSignature] methodReturnLength]);
-        [returnValue getValue:buffer];
-        [anInvocation setReturnValue:buffer];
-        free(buffer);
-}
-
-@end