Allow to add new :db/ident mappings.

src/datomish/db.cljc

@@ -527,6 +527,45 @@
 
 ;; Upsert or allocate id-literals.
 
+(defn- is-ident? [db [_ a & _]]
+  (= a (get-in db [:idents :db/ident])))
+
+(defn process-db-idents
+  "Transactions may add idents, install new partitions, and install new schema attributes.
+  Handle :db/ident assertions here."
+  [db tx-data]
+  {:pre [(db? db)
+         ;; (report? report)
+         ]}
+  ;; TODO: use q to filter the report!
+  (let [original-db db
+        original-ident-assertions (filter (partial is-ident? db) tx-data)]
+    (loop [db original-db
+           ident-assertions original-ident-assertions]
+      (let [[ia & ias] ident-assertions]
+        (cond
+          (nil? ia)
+          db
+
+          (not (:added ia))
+          (raise "Retracting a :db/ident is not yet supported, got " ia
+                 {:error :schema/idents
+                  :op    ia })
+
+          :else
+          ;; Added.
+          (let [ident (:v ia)]
+            ;; TODO: accept re-assertions?
+            (when (get-in db [:idents ident])
+              (raise "Re-asserting a :db/ident is not yet supported, got " ia
+                     {:error :schema/idents
+                      :op    ia }))
+            (if (keyword? ident)
+              (recur (assoc-in db [:idents ident] (:e ia)) ias)
+              (raise "Cannot assert a :db/ident with a non-keyword value, got " ia
+                     {:error :schema/idents
+                      :op    ia }))))))))
+
 (defn <with [db tx-data]
   (go-pair
     (let [report (<? (<transact-tx-data db 0xdeadbeef ;; TODO
@@ -544,8 +583,9 @@
                      (<?)
 
                      (<advance-tx)
-                     (<?))]
+                     (<?)
 
+                     (process-db-idents (:tx-data report)))]
       (-> report
           (assoc-in [:db-after] db-after)))))
 

test/datomish/db_test.cljc

@@ -147,3 +147,32 @@
 
         (finally
           (<? (dm/close-db db)))))))
+
+(deftest-async test-add-ident
+  (with-tempfile [t (tempfile)]
+    (let [c    (<? (s/<sqlite-connection t))
+          db   (<? (dm/<db-with-sqlite-connection c))
+          conn (dm/connection-with-db db)
+          now  -1]
+      (try
+        (let [report   (<? (dm/<transact! conn [[:db/add 44 :db/ident :name]] now))
+              db-after (:db-after report)
+              tx       (:current-tx db-after)]
+          (is (= (:name (dm/idents db-after)) 44)))
+
+        ;; TODO: This should fail, but doesn't, due to stringification of :name.
+        ;; (is (thrown-with-msg?
+        ;;       ExceptionInfo #"Retracting a :db/ident is not yet supported, got "
+        ;;       (<? (dm/<transact! conn [[:db/retract 44 :db/ident :name]] now))))
+
+        ;; ;; Renaming looks like retraction and then assertion.
+        ;; (is (thrown-with-msg?
+        ;;       ExceptionInfo #"Retracting a :db/ident is not yet supported, got"
+        ;;       (<? (dm/<transact! conn [[:db/add 44 :db/ident :other-name]] now))))
+
+        ;; (is (thrown-with-msg?
+        ;;       ExceptionInfo #"Re-asserting a :db/ident is not yet supported, got"
+        ;;       (<? (dm/<transact! conn [[:db/add 55 :db/ident :name]] now))))
+
+        (finally
+          (<? (dm/close-db db)))))))