grand PR to port the remaining paths (FieldPath and ResourcePath). (#865)

* naively remove FSTPath import and source/test files.

* port FieldPath, part I

* port FieldPath, part II

* port ResourcePath, part I

* port ResourcePath, part II

* the grand commit to fix build errors

* use testutil:: helper instead of those from FSTHelpers

* fix test and lint

* use c_str in errmsg directly

* fix

* fix

* make code clean

* fix integration test I missed

* fix to avoid naming collision in preprocessor

* address changes

* address changes

* address changes

* fix: fieldMask are actually shared with different context.

* address changes

* address changes

3 files changed, 11 insertions, 20 deletions

diff --git a/Firestore/Source/Core/FSTFirestoreClient.mm b/Firestore/Source/Core/FSTFirestoreClient.mm
index 288cbe2..9f0779a 100644
--- a/Firestore/Source/Core/FSTFirestoreClient.mm
+++ b/Firestore/Source/Core/FSTFirestoreClient.mm
@@ -205,7 +205,7 @@ NS_ASSUME_NONNULL_BEGIN
 - (void)userDidChange:(const User &)user {
   [self.workerDispatchQueue verifyIsCurrentQueue];
 
-  FSTLog(@"User Changed: %@", util::WrapNSStringNoCopy(user.uid()));
+  FSTLog(@"User Changed: %s", user.uid().c_str());
   [self.syncEngine userDidChange:user];
 }
 
diff --git a/Firestore/Source/Core/FSTQuery.mm b/Firestore/Source/Core/FSTQuery.mm
index c10b94d..43b6356 100644
--- a/Firestore/Source/Core/FSTQuery.mm
+++ b/Firestore/Source/Core/FSTQuery.mm
@@ -23,7 +23,6 @@
 #import "Firestore/Source/Model/FSTDocument.h"
 #import "Firestore/Source/Model/FSTDocumentKey.h"
 #import "Firestore/Source/Model/FSTFieldValue.h"
-#import "Firestore/Source/Model/FSTPath.h"
 #import "Firestore/Source/Util/FSTAssert.h"
 
 #include "Firestore/core/src/firebase/firestore/model/field_path.h"
@@ -153,8 +152,7 @@ NSString *FSTStringFromQueryRelationOperator(FSTRelationFilterOperator filterOpe
     NSComparisonResult comparison = FSTDocumentKeyComparator(document.key, refValue.value);
     return [self matchesComparison:comparison];
   } else {
-    return [self
-        matchesValue:[document fieldForPath:[FSTFieldPath fieldPathWithCPPFieldPath:self.field]]];
+    return [self matchesValue:[document fieldForPath:self.field]];
   }
 }
 
@@ -220,8 +218,7 @@ NSString *FSTStringFromQueryRelationOperator(FSTRelationFilterOperator filterOpe
 }
 
 - (BOOL)matchesDocument:(FSTDocument *)document {
-  FSTFieldValue *fieldValue =
-      [document fieldForPath:[FSTFieldPath fieldPathWithCPPFieldPath:self.field]];
+  FSTFieldValue *fieldValue = [document fieldForPath:self.field];
   return fieldValue != nil && [fieldValue isEqual:[FSTNullValue nullValue]];
 }
 
@@ -267,8 +264,7 @@ NSString *FSTStringFromQueryRelationOperator(FSTRelationFilterOperator filterOpe
 }
 
 - (BOOL)matchesDocument:(FSTDocument *)document {
-  FSTFieldValue *fieldValue =
-      [document fieldForPath:[FSTFieldPath fieldPathWithCPPFieldPath:self.field]];
+  FSTFieldValue *fieldValue = [document fieldForPath:self.field];
   return fieldValue != nil && [fieldValue isEqual:[FSTDoubleValue nanValue]];
 }
 
@@ -338,10 +334,8 @@ NSString *FSTStringFromQueryRelationOperator(FSTRelationFilterOperator filterOpe
   if (_field == FieldPath::KeyFieldPath()) {
     result = FSTDocumentKeyComparator(document1.key, document2.key);
   } else {
-    FSTFieldValue *value1 =
-        [document1 fieldForPath:[FSTFieldPath fieldPathWithCPPFieldPath:self.field]];
-    FSTFieldValue *value2 =
-        [document2 fieldForPath:[FSTFieldPath fieldPathWithCPPFieldPath:self.field]];
+    FSTFieldValue *value1 = [document1 fieldForPath:self.field];
+    FSTFieldValue *value2 = [document2 fieldForPath:self.field];
     FSTAssert(value1 != nil && value2 != nil,
               @"Trying to compare documents on fields that don't exist.");
     result = [value1 compare:value2];
@@ -434,8 +428,7 @@ NSString *FSTStringFromQueryRelationOperator(FSTRelationFilterOperator filterOpe
       FSTReferenceValue *refValue = (FSTReferenceValue *)fieldValue;
       comparison = [refValue.value compare:document.key];
     } else {
-      FSTFieldValue *docValue =
-          [document fieldForPath:[FSTFieldPath fieldPathWithCPPFieldPath:sortOrderComponent.field]];
+      FSTFieldValue *docValue = [document fieldForPath:sortOrderComponent.field];
       FSTAssert(docValue != nil, @"Field should exist since document matched the orderBy already.");
       comparison = [fieldValue compare:docValue];
     }
@@ -590,9 +583,9 @@ NSString *FSTStringFromQueryRelationOperator(FSTRelationFilterOperator filterOpe
       }
     } else {
       FSTAssert(!inequalityField || *inequalityField == *firstSortOrderField,
-                @"First orderBy %@ should match inequality field %@.",
-                util::WrapNSStringNoCopy(firstSortOrderField->CanonicalString()),
-                util::WrapNSStringNoCopy(inequalityField->CanonicalString()));
+                @"First orderBy %s should match inequality field %s.",
+                firstSortOrderField->CanonicalString().c_str(),
+                inequalityField->CanonicalString().c_str());
 
       __block BOOL foundKeyOrder = NO;
 
@@ -791,8 +784,7 @@ NSString *FSTStringFromQueryRelationOperator(FSTRelationFilterOperator filterOpe
   for (FSTSortOrder *orderBy in self.explicitSortOrders) {
     const FieldPath &fieldPath = orderBy.field;
     // order by key always matches
-    if (fieldPath != FieldPath::KeyFieldPath() &&
-        [document fieldForPath:[FSTFieldPath fieldPathWithCPPFieldPath:fieldPath]] == nil) {
+    if (fieldPath != FieldPath::KeyFieldPath() && [document fieldForPath:fieldPath] == nil) {
       return NO;
     }
   }
diff --git a/Firestore/Source/Core/FSTSyncEngine.mm b/Firestore/Source/Core/FSTSyncEngine.mm
index a857f5a..61fac7d 100644
--- a/Firestore/Source/Core/FSTSyncEngine.mm
+++ b/Firestore/Source/Core/FSTSyncEngine.mm
@@ -36,7 +36,6 @@
 #import "Firestore/Source/Model/FSTDocumentKey.h"
 #import "Firestore/Source/Model/FSTDocumentSet.h"
 #import "Firestore/Source/Model/FSTMutationBatch.h"
-#import "Firestore/Source/Model/FSTPath.h"
 #import "Firestore/Source/Remote/FSTRemoteEvent.h"
 #import "Firestore/Source/Util/FSTAssert.h"
 #import "Firestore/Source/Util/FSTDispatchQueue.h"