[Autofill] Autofill fails to fill credit card number when split across fields.

components/autofill/core/browser/credit_card_field.cc

Index: components/autofill/core/browser/credit_card_field.cc
diff --git a/components/autofill/core/browser/credit_card_field.cc b/components/autofill/core/browser/credit_card_field.cc
index 09dab1e48d796800fda5065ee6cb54075fd5697a..1d0812b7e8675d209eaa98cf146cfbf9c0cf3a77 100644
--- a/components/autofill/core/browser/credit_card_field.cc
+++ b/components/autofill/core/browser/credit_card_field.cc
@@ -6,6 +6,8 @@
 
 #include <stddef.h>
 
+#include <algorithm>
+
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
@@ -19,6 +21,8 @@
 
 namespace autofill {
 
+static const size_t kMaxValidCardNumberSize = 19;
+
 // static
 FormField* CreditCardField::Parse(AutofillScanner* scanner) {
   if (scanner->IsEnd())
@@ -89,8 +93,26 @@ FormField* CreditCardField::Parse(AutofillScanner* scanner) {
     }
 
     pattern = base::UTF8ToUTF16(autofill::kCardNumberRe);
-    if (!credit_card_field->number_ &&
-        ParseField(scanner, pattern, &credit_card_field->number_)) {
+    const AutofillField* cc_number_field;
+    if (ParseField(scanner, pattern, &cc_number_field)) {
+      // Avoid autofilling any credit card number field having very low or high
+      // |start_index| on the HTML form.
+      size_t start_index = 0;
+      if (!credit_card_field->numbers_.empty()) {
+        size_t last_number_field_size =
+            credit_card_field->numbers_.back()
+                ->credit_card_number_start_index() +

[Evan Stade, 2014/08/12 16:05:07]

style-wise, a lot of this seems off to me. Could you run git cl format?

[Pritam Nikam, 2014/08/12 18:39:11]

It's after git cl format only :)

+            credit_card_field->numbers_.back()->max_length;
+        if (!last_number_field_size ||

[Evan Stade, 2014/08/12 16:05:07]

please don't implicitly convert size_t to boolean. Replace this with
last_number_field_size == OU

[Pritam Nikam, 2014/08/12 18:39:11]

Done.

+            last_number_field_size >= kMaxValidCardNumberSize)
+          return NULL;

[Evan Stade, 2014/08/12 16:05:07]

\n

[Pritam Nikam, 2014/08/12 18:39:11]

Done.

+        start_index = last_number_field_size;
+      }
+
+      AutofillField* current_number_field =
+          const_cast<AutofillField*>(cc_number_field);

[Evan Stade, 2014/08/12 16:05:07]

you still have this const_cast... I agree with Ilya that the signature of
ParseField ought to be changed.

[Pritam Nikam, 2014/08/12 18:39:11]

[Same as my previous comments]
I didn't get any alternative approach to fix const_cast<> used here. 

Changing ParseField() signature alone will not help,  have to introduce lots of
signature changes as it's just a wrapper API. And may be doing that will have
ripple effect across [form-field, scanner and cursor modules]. Isn't it an
overkill for this issue.

I'm kind of blocked here, please guide me how can I solve this problem.

[Evan Stade, 2014/08/12 19:19:55]

What is the cursor module?
the code becomes a lot harder to follow if there are a ton of false consts
sprinkled throughout, so no.
Remove all the consts you need to. I think this will only touch FormField and
AutofillScanner.

+      current_number_field->set_credit_card_number_start_index(start_index);
+      credit_card_field->numbers_.push_back(current_number_field);
       continue;
     }
 
@@ -167,7 +189,8 @@ FormField* CreditCardField::Parse(AutofillScanner* scanner) {
   // a strong enough signal that this is a credit card.  It is possible that
   // the number and name were parsed in a separate part of the form.  So if
   // the cvc and date were found independently they are returned.
-  if ((credit_card_field->number_ || credit_card_field->verification_) &&
+  if ((!credit_card_field->numbers_.empty() ||
+       credit_card_field->verification_) &&
       (credit_card_field->expiration_date_ ||
        (credit_card_field->expiration_month_ &&
         credit_card_field->expiration_year_))) {
@@ -182,7 +205,6 @@ CreditCardField::CreditCardField()
     : cardholder_(NULL),
       cardholder_last_(NULL),
       type_(NULL),
-      number_(NULL),
       verification_(NULL),
       expiration_month_(NULL),
       expiration_year_(NULL),
@@ -190,8 +212,17 @@ CreditCardField::CreditCardField()
       is_two_digit_year_(false) {
 }
 
+CreditCardField::~CreditCardField() {
+}
+
 bool CreditCardField::ClassifyField(ServerFieldTypeMap* map) const {
-  bool ok = AddClassification(number_, CREDIT_CARD_NUMBER, map);
+  bool ok = true;
+  for (std::vector<const AutofillField*>::const_iterator it = numbers_.begin();
+       it != numbers_.end();
+       ++it) {
+    ok = ok && AddClassification(*it, CREDIT_CARD_NUMBER, map);
+  }
+
   ok = ok && AddClassification(type_, CREDIT_CARD_TYPE, map);
   ok = ok && AddClassification(verification_, CREDIT_CARD_VERIFICATION_CODE,
                                map);