Add more warnings to for the ObjC runtime build

Working on https://github.com/google/protobuf/issues/1599, specifically:
- Turn on more warnings that the Xcode UI calls out with individual controls.
- Manually add:
  -Wundef
  -Wswitch-enum
- Manually add and then diable in the unittests because of XCTest's headers:
  -Wreserved-id-macro
  -Wdocumentation-unknown-command
- Manually add -Wdirect-ivar-access, but disable it for the unittests and in
  the library code (via #pragmas to suppress it). This is done so proto users
  can enable the warning.

1 files changed, 19 insertions, 5 deletions

diff --git a/objectivec/GPBUtilities.m b/objectivec/GPBUtilities.m
index 447c749a..89deb2e7 100644
--- a/objectivec/GPBUtilities.m
+++ b/objectivec/GPBUtilities.m
@@ -39,6 +39,12 @@
 #import "GPBUnknownField.h"
 #import "GPBUnknownFieldSet.h"
 
+// Direct access is use for speed, to avoid even internally declaring things
+// read/write, etc. The warning is enabled in the project to ensure code calling
+// protos can turn on -Wdirect-ivar-access without issues.
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdirect-ivar-access"
+
 static void AppendTextFormatForMessage(GPBMessage *message,
                                        NSMutableString *toStr,
                                        NSString *lineIndent);
@@ -891,7 +897,7 @@ void GPBSetMessageGroupField(GPBMessage *self,
 
 // Only exists for public api, no core code should use this.
 id GPBGetMessageRepeatedField(GPBMessage *self, GPBFieldDescriptor *field) {
-#if DEBUG
+#if defined(DEBUG) && DEBUG
   if (field.fieldType != GPBFieldTypeRepeated) {
     [NSException raise:NSInvalidArgumentException
                 format:@"%@.%@ is not a repeated field.",
@@ -903,7 +909,7 @@ id GPBGetMessageRepeatedField(GPBMessage *self, GPBFieldDescriptor *field) {
 
 // Only exists for public api, no core code should use this.
 void GPBSetMessageRepeatedField(GPBMessage *self, GPBFieldDescriptor *field, id array) {
-#if DEBUG
+#if defined(DEBUG) && DEBUG
   if (field.fieldType != GPBFieldTypeRepeated) {
     [NSException raise:NSInvalidArgumentException
                 format:@"%@.%@ is not a repeated field.",
@@ -957,7 +963,7 @@ void GPBSetMessageRepeatedField(GPBMessage *self, GPBFieldDescriptor *field, id
   GPBSetObjectIvarWithField(self, field, array);
 }
 
-#if DEBUG
+#if defined(DEBUG) && DEBUG
 static NSString *TypeToStr(GPBDataType dataType) {
   switch (dataType) {
     case GPBDataTypeBool:
@@ -993,7 +999,7 @@ static NSString *TypeToStr(GPBDataType dataType) {
 
 // Only exists for public api, no core code should use this.
 id GPBGetMessageMapField(GPBMessage *self, GPBFieldDescriptor *field) {
-#if DEBUG
+#if defined(DEBUG) && DEBUG
   if (field.fieldType != GPBFieldTypeMap) {
     [NSException raise:NSInvalidArgumentException
                 format:@"%@.%@ is not a map<> field.",
@@ -1006,7 +1012,7 @@ id GPBGetMessageMapField(GPBMessage *self, GPBFieldDescriptor *field) {
 // Only exists for public api, no core code should use this.
 void GPBSetMessageMapField(GPBMessage *self, GPBFieldDescriptor *field,
                            id dictionary) {
-#if DEBUG
+#if defined(DEBUG) && DEBUG
   if (field.fieldType != GPBFieldTypeMap) {
     [NSException raise:NSInvalidArgumentException
                 format:@"%@.%@ is not a map<> field.",
@@ -1133,6 +1139,8 @@ static void AppendTextFormatForMapMessageField(
       [toStr appendString:@"\n"];
 
       [toStr appendString:valueLine];
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wswitch-enum"
       switch (valueDataType) {
         case GPBDataTypeString:
           AppendStringEscaped(value, toStr);
@@ -1153,6 +1161,7 @@ static void AppendTextFormatForMapMessageField(
           NSCAssert(NO, @"Can't happen");
           break;
       }
+#pragma clang diagnostic pop
       [toStr appendString:@"\n"];
 
       [toStr appendString:msgEnd];
@@ -1174,6 +1183,8 @@ static void AppendTextFormatForMapMessageField(
       }
 
       [toStr appendString:valueLine];
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wswitch-enum"
       switch (valueDataType) {
         case GPBDataTypeString:
           AppendStringEscaped(valueObj, toStr);
@@ -1211,6 +1222,7 @@ static void AppendTextFormatForMapMessageField(
           [toStr appendString:valueObj];
           break;
       }
+#pragma clang diagnostic pop
       [toStr appendString:@"\n"];
 
       [toStr appendString:msgEnd];
@@ -1706,6 +1718,8 @@ NSString *GPBDecodeTextFormatName(const uint8_t *decodeData, int32_t key,
   return result;
 }
 
+#pragma clang diagnostic pop
+
 #pragma mark - GPBMessageSignatureProtocol
 
 // A series of selectors that are used solely to get @encoding values