src/third_party/ocmock/OCMock/OCMBoxedReturnValueProvider.mm

   1 //---------------------------------------------------------------------------------------
   2 //  $Id$
   3 //  Copyright (c) 2009 by Mulle Kybernetik. See License file for details.
   4 //---------------------------------------------------------------------------------------
   5
   6 #import "OCMBoxedReturnValueProvider.h"
   7 #import <objc/runtime.h>
   8
   9 #if defined(__clang__)
  10 #include <vector>  // for _LIBCPP_ABI_VERSION to detect if using libc++
  11 #endif
  12
  13 #if defined(__clang__) && defined(_LIBCPP_ABI_VERSION)
  14 namespace {
  15 // Default stack size to use when checking for matching opening and closing
  16 // characters (<> and {}). This is used to reduce the number of allocations
  17 // in AdvanceTypeDescriptionPointer function.
  18 const size_t kDefaultStackSize = 32;
  19
  20 // Move to the next pertinent character in a type description. This skips
  21 // all the field expansion that clang includes in the type description when
  22 // compiling with libc++.
  23 //
  24 // See inner comment of -isValueTypeCompatibleWithInvocation: for more details.
  25 // Returns true if the pointer was advanced, false if the type description was
  26 // not correctly parsed.
  27 bool AdvanceTypeDescriptionPointer(const char *&typeDescription) {
  28         if (!*typeDescription)
  29                 return true;
  30
  31         ++typeDescription;
  32         if (*typeDescription != '=')
  33                 return true;
  34
  35         ++typeDescription;
  36         std::vector<char> stack;
  37         stack.reserve(kDefaultStackSize);
  38         while (*typeDescription) {
  39                 const char current = *typeDescription;
  40                 if (current == '<' || current == '{') {
  41                         stack.push_back(current);
  42                 } else if (current == '>' || current == '}') {
  43                         if (!stack.empty()) {
  44                                 const char opening = stack.back();
  45                                 if ((opening == '<' && current != '>') ||
  46                                                 (opening == '{' && current != '}')) {
  47                                         return false;
  48                                 }
  49                                 stack.pop_back();
  50                         } else {
  51                                 return current == '}';
  52                         }
  53                 } else if (current == ',' && stack.empty()) {
  54                         return true;
  55                 }
  56                 ++typeDescription;
  57         }
  58         return true;
  59 }
  60 }
  61 #endif  // defined(__clang__) && defined(_LIBCPP_ABI_VERSION)
  62
  63 @interface OCMBoxedReturnValueProvider ()
  64
  65 - (BOOL)isValueTypeCompatibleWithInvocation:(NSInvocation *)anInvocation;
  66
  67 @end
  68
  69 @implementation OCMBoxedReturnValueProvider
  70
  71 - (BOOL)isValueTypeCompatibleWithInvocation:(NSInvocation *)anInvocation {
  72         const char *returnType = [[anInvocation methodSignature] methodReturnType];
  73         const char *valueType = [(NSValue *)returnValue objCType];
  74
  75 #if defined(__aarch64__) || defined(__x86_64__)
  76         // ARM64 uses 'B' for BOOLs in method signature but 'c' in NSValue. That case
  77         // should match.
  78         if (strcmp(returnType, "B") == 0 && strcmp(valueType, "c") == 0)
  79                 return YES;
  80 #endif  // defined(__aarch64__) || defined(__x86_64__)
  81
  82 #if defined(__clang__) && defined(_LIBCPP_ABI_VERSION)
  83         // The type representation of the return type of the invocation, and the
  84         // type representation passed to NSValue are not the same for C++ objects
  85         // when compiling with libc++ with clang.
  86         //
  87         // In that configuration, the C++ class are expanded to list the types of
  88         // the fields, but the depth of the expansion for templated types is larger
  89         // for the value stored in the NSValue.
  90         //
  91         // For example, when creating a OCMOCK_VALUE with a GURL object (from the
  92         // Chromium project), then the two types representations are:
  93         //
  94         // r^{GURL={basic_string<char, std::__1::char_traits<char>, std::__1::alloca
  95         // tor<char> >={__compressed_pair<std::__1::basic_string<char, std::__1::cha
  96         // r_traits<char>, std::__1::allocator<char> >::__rep, std::__1::allocator<c
  97         // har> >={__rep}}}B{Parsed={Component=ii}{Component=ii}{Component=ii}{Compo
  98         // nent=ii}{Component=ii}{Component=ii}{Component=ii}{Component=ii}^{Parsed}
  99         // }{scoped_ptr<GURL, base::DefaultDeleter<GURL> >={scoped_ptr_impl<GURL, ba
 100         // se::DefaultDeleter<GURL> >={Data=^{GURL}}}}}
 101         //
 102         // r^{GURL={basic_string<char, std::__1::char_traits<char>, std::__1::alloca
 103         // tor<char> >={__compressed_pair<std::__1::basic_string<char, std::__1::cha
 104         // r_traits<char>, std::__1::allocator<char> >::__rep, std::__1::allocator<c
 105         // har> >={__rep=(?={__long=II*}{__short=(?=Cc)[11c]}{__raw=[3L]})}}}B{Parse
 106         // d={Component=ii}{Component=ii}{Component=ii}{Component=ii}{Component=ii}{
 107         // Component=ii}{Component=ii}{Component=ii}^{Parsed}}{scoped_ptr<GURL, base
 108         // ::DefaultDeleter<GURL> >={scoped_ptr_impl<GURL, base::DefaultDeleter<GURL
 109         // > >={Data=^{GURL}}}}}
 110         //
 111         // Since those types should be considered equals, we un-expand them during
 112         // the comparison. For that, we remove everything following an "=" until we
 113         // meet a non-matched "}" or a ",".
 114
 115         while (*returnType && *valueType) {
 116                 if (*returnType != *valueType)
 117                         return NO;
 118
 119                 if (!AdvanceTypeDescriptionPointer(returnType))
 120                         return NO;
 121
 122                 if (!AdvanceTypeDescriptionPointer(valueType))
 123                         return NO;
 124         }
 125
 126         return !*returnType && !*valueType;
 127 #else
 128         return strcmp(returnType, valueType) == 0;
 129 #endif  // defined(__clang__) && defined(_LIBCPP_ABI_VERSION)
 130 }
 131
 132 - (void)handleInvocation:(NSInvocation *)anInvocation
 133 {
 134         if (![self isValueTypeCompatibleWithInvocation:anInvocation]) {
 135                 const char *returnType = [[anInvocation methodSignature] methodReturnType];
 136                 const char *valueType = [(NSValue *)returnValue objCType];
 137                 @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];
 138         }
 139         void *buffer = malloc([[anInvocation methodSignature] methodReturnLength]);
 140         [returnValue getValue:buffer];
 141         [anInvocation setReturnValue:buffer];
 142         free(buffer);
 143 }
 144
 145 @end