Added counter with unit tests.

README.md

@@ -3,6 +3,8 @@
 A link shortener written as a learning tool for clojure, ring, noir,
 drift (migrations), and hsqldb
 
+This is very much a work in progress.  There is nothing functional about it, yet.
+
 ## Prerequisites
 
 1. Download hsqldb 2.2.5
@@ -22,12 +24,17 @@ drift (migrations), and hsqldb
     ```bash
     lein deps
     ```
+2. Run the tests
+
+    ```bash
+    lein test
+    ```
 2. Run the migrations
 
     ```bash
     lein migrate -version 1
     ```
-3. Download dependencies and run the server
+3. Run the server
 
     ```bash
     lein run

src/config/migrate_config.clj

@@ -3,7 +3,7 @@
   (:use [link-shortener.db :only (db)]))
 
 (defn 
-#^{:doc "Get the current schema migration number"}
+ ^{:doc "Get the current schema migration number"}
   db-version []
   (try 
     (sql/with-connection db ;; Pull the version number from the schema_migrations table
@@ -13,7 +13,7 @@
     (catch Exception _ 0))) ;; If there is an exception, return version=0
 
 (defn 
-#^{:doc "Set the current schema migration version"}
+ ^{:doc "Set the current schema migration version"}
   update-db-version [new-version]
   (if (not= 0 new-version)
     (sql/with-connection db

src/link_shortener/counter.clj

@@ -0,0 +1,25 @@
+(ns link-shortener.counter)
+
+(def 
+  ^{:private true}
+  alpha "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")
+
+(def alpha-length (.length alpha))
+
+(defn allButLast [s]
+  (if (= (.length s) 0)
+    ""
+    (.substring s 0 (- (.length s) 1))))
+
+(defn nextInAlpha [c] 
+  (let [index (inc (.indexOf alpha (str c)))
+        index (if (= alpha-length index) 0 index)]
+    (str (.charAt alpha index))))
+
+(defn n [s]
+  (loop [f (allButLast s)
+         l (nextInAlpha (last s))
+         acc ""]
+    (if (not= l "0")
+      (str f l acc)
+      (recur (allButLast f) (nextInAlpha (last f)) (str l acc)))))

src/migrations/001_schema_migrations.clj

@@ -3,29 +3,27 @@
   (:use [link-shortener.db :only (db)]))
 
 (defn 
-#^{:doc "Create the schema_migrations table"}
+ ^{:doc "Create the schema_migrations table"}
   create-migrations-table []
   (sql/create-table
     :schema_migrations
     [:version :int]))
 
 (defn 
-#^{:doc "Drop the schema_migrations table"}
+ ^{:doc "Drop the schema_migrations table"}
   drop-migrations-table []
   (try 
     (sql/drop-table :schema_migrations)
     (catch Exception _)))
 
 (defn
-#^{:doc "Migrates the database up to version 1."}
+ ^{:doc "Migrates the database up to version 1."}
   up []
-  (println "migrations.001-schema-migrations up...")
   (sql/with-connection db
         (sql/transaction (create-migrations-table))))
 
 (defn
-#^{:doc "Migrates the database down from version 1."}
+ ^{:doc "Migrates the database down from version 1."}
   down []
-  (println "migrations.001-schema-migrations down...")
   (sql/with-connection db
         (sql/transaction (drop-migrations-table))))

test/link_shortener/test/counter.clj

@@ -0,0 +1,22 @@
+(ns link-shortener.test.counter
+  (:use [link-shortener.counter])
+  (:use clojure.test))
+
+(deftest test_nextInAlpha
+  (is (= (nextInAlpha "z") "A") "Should have been A.")
+  (is (= (nextInAlpha "Z") "0") "Should have been 0.")
+  (is (= (nextInAlpha "0") "1") "Should have been 1.")
+  (is (= (nextInAlpha \Z) "0") "Didn't handle char correctly.")
+  (is (= (nextInAlpha "") "1") "Didn't handle emptry string correctly."))
+
+(deftest test_allButLast 
+  (is (= (allButLast "asdf") "asd") "Why didn't it return asd?")
+  (is (= (allButLast "a") "") "This shouldn't return anything.")
+  (is (= (allButLast "") "") "This shouldn't return anything.")) 
+
+(deftest test_multichar
+  (is (= (n "ab") "ac") "Why didn't it return ac?")
+  (is (= (n "Z") "10") "Why didn't it return 10?")
+  (is (= (n "ZZ") "100") "Why didn't it return 100?")
+  (is (= (n "zZ") "A0") "Why didn't it return A0?")
+  (is (= (n "asdfZZ") "asdg00") "Why didn't it return asdg00?"))