[account.cpp] add more account metadata - assoc account

the tag denotes the type of associated account eg. "dividend"
"capgains" "cash" "fees"

libgnucash/engine/Account.cpp

@@ -2579,6 +2579,34 @@ xaccAccountSetNotes (Account *acc, const char *str)
     set_kvp_string_tag (acc, "notes", str);
 }
 
+
+void
+xaccAccountSetAssociatedAccount (Account *acc, const char *tag, const Account* assoc_acct)
+{
+    g_return_if_fail (GNC_IS_ACCOUNT(acc));
+    g_return_if_fail (tag && *tag);
+
+    std::vector<std::string> path = { "associated-account", tag };
+    xaccAccountBeginEdit(acc);
+
+    PINFO ("setting %s assoc %s account = %s", xaccAccountGetName (acc), tag,
+           assoc_acct ? xaccAccountGetName (assoc_acct) : nullptr);
+
+    if (GNC_IS_ACCOUNT(assoc_acct))
+    {
+        GValue v = G_VALUE_INIT;
+        g_value_init (&v, GNC_TYPE_GUID);
+        g_value_set_static_boxed (&v, xaccAccountGetGUID (assoc_acct));
+        qof_instance_set_path_kvp (QOF_INSTANCE (acc), &v, path);
+        g_value_unset (&v);
+    }
+    else
+        qof_instance_set_path_kvp (QOF_INSTANCE (acc), nullptr, path);
+
+    mark_account (acc);
+    xaccAccountCommitEdit(acc);
+}
+
 void
 xaccAccountSetCommodity (Account * acc, gnc_commodity * com)
 {
@@ -3367,6 +3395,28 @@ xaccAccountGetNotes (const Account *acc)
     return rv;
 }
 
+Account*
+xaccAccountGetAssociatedAccount (const Account *acc, const char *tag)
+{
+    g_return_val_if_fail (GNC_IS_ACCOUNT(acc), nullptr);
+    g_return_val_if_fail (tag && *tag, nullptr);
+
+    GValue v = G_VALUE_INIT;
+    qof_instance_get_path_kvp (QOF_INSTANCE (acc), &v, { "associated-account", tag });
+
+    auto guid = static_cast<GncGUID*>(G_VALUE_HOLDS_BOXED (&v) ? g_value_get_boxed(&v) : nullptr);
+    g_value_unset (&v);
+
+    if (!guid)
+        return nullptr;
+
+    auto assoc_acct = xaccAccountLookup (guid, gnc_account_get_book (acc));
+    PINFO ("retuning %s assoc %s account = %s", xaccAccountGetName (acc), tag,
+           xaccAccountGetName (assoc_acct));
+    return assoc_acct;
+}
+
+
 gnc_commodity *
 DxaccAccountGetCurrency (const Account *acc)
 {

libgnucash/engine/Account.h

@@ -312,6 +312,11 @@ typedef enum
     void xaccAccountSetSortReversed (Account *account, gboolean sortreversed);
     /** Set the account's notes */
     void xaccAccountSetNotes (Account *account, const char *notes);
+
+    /** Set the account's associated account e.g. stock account -> dividend account */
+    void xaccAccountSetAssociatedAccount (Account *acc, const char *tag,
+                                          const Account *assoc_acct);
+
     /** Set the last num field of an Account */
     void xaccAccountSetLastNum (Account *account, const char *num);
     /** Set the account's lot order policy */
@@ -416,6 +421,9 @@ typedef enum
     gboolean xaccAccountGetSortReversed (const Account *account);
     /** Get the account's notes */
     const char * xaccAccountGetNotes (const Account *account);
+
+    /** Get the account's associated account e.g. stock account -> dividend account */
+    Account* xaccAccountGetAssociatedAccount (const Account *acc, const char *tag);
     /** Get the last num field of an Account */
     const char * xaccAccountGetLastNum (const Account *account);
     /** Get the account's lot order policy */

libgnucash/engine/test/utest-Account.cpp

@@ -1237,6 +1237,25 @@ test_gnc_account_kvp_setters_getters (Fixture *fixture, gconstpointer pData)
     xaccAccountSetNotes (account, nullptr);
     g_assert_cmpstr (xaccAccountGetNotes (account), ==, nullptr);
 
+    // Associated Account getter/setter
+    g_assert_null (xaccAccountGetAssociatedAccount (account, "test"));
+
+    g_test_expect_message ("gnc.engine", G_LOG_LEVEL_CRITICAL,
+                           "*xaccAccountSetAssociatedAccount*assertion*tag && *tag*");
+    xaccAccountSetAssociatedAccount (account, nullptr, account);
+    g_test_assert_expected_messages();
+
+    g_test_expect_message ("gnc.engine", G_LOG_LEVEL_CRITICAL,
+                           "*xaccAccountSetAssociatedAccount*assertion*GNC_IS_ACCOUNT(acc)*");
+    xaccAccountSetAssociatedAccount (nullptr, "test", account);
+    g_test_assert_expected_messages();
+
+    xaccAccountSetAssociatedAccount (account, "test", account);
+    g_assert_true (xaccAccountGetAssociatedAccount (account, "test") == account);
+
+    xaccAccountSetAssociatedAccount (account, "test", nullptr);
+    g_assert_null (xaccAccountGetAssociatedAccount (account, "test"));
+
     // Balance Limits getter/setter
     g_assert_true (xaccAccountGetHigherBalanceLimit (account, &balance_limit) == false);
     g_assert_true (xaccAccountGetLowerBalanceLimit (account, &balance_limit) == false);