Implement 'workspace next/prev' (+test)

src/cmdparse.l

@@ -71,6 +71,11 @@ EOL (\r?\n)
     cmdyycolumn = 1;
 }
 
+    /* the next/prev tokens are here to recognize them *before* handling
+     * strings ('workspace' command) */
+next                            { return TOK_NEXT; }
+prev                            { return TOK_PREV; }
+
 <WANT_STRING>\"[^\"]+\"         {
                                   BEGIN(INITIAL);
                                   /* strip quotes */
@@ -120,7 +125,6 @@ workspace                       { WS_STRING; return TOK_WORKSPACE; }
 focus                           { return TOK_FOCUS; }
 move                            { return TOK_MOVE; }
 open                            { return TOK_OPEN; }
-prev                            { return TOK_PREV; }
 split                           { return TOK_SPLIT; }
 horizontal                      { return TOK_HORIZONTAL; }
 vertical                        { return TOK_VERTICAL; }

src/cmdparse.y

@@ -142,6 +142,7 @@ char *parse_cmd(const char *new) {
 %token              TOK_FOCUS           "focus"
 %token              TOK_MOVE            "move"
 %token              TOK_OPEN            "open"
+%token              TOK_NEXT            "next"
 %token              TOK_PREV            "prev"
 %token              TOK_SPLIT           "split"
 %token              TOK_HORIZONTAL      "horizontal"
@@ -487,7 +488,17 @@ optional_kill_mode:
     ;
 
 workspace:
-    TOK_WORKSPACE STR
+    TOK_WORKSPACE TOK_NEXT
+    {
+        workspace_next();
+        tree_render();
+    }
+    | TOK_WORKSPACE TOK_PREV
+    {
+        workspace_prev();
+        tree_render();
+    }
+    | TOK_WORKSPACE STR
     {
         printf("should switch to workspace %s\n", $2);
         workspace_show($2);

src/workspace.c

@@ -231,6 +231,32 @@ void workspace_show(const char *num) {
     ipc_send_event("workspace", I3_IPC_EVENT_WORKSPACE, "{\"change\":\"focus\"}");
 }
 
+/*
+ * Focuses the next workspace.
+ *
+ */
+void workspace_next() {
+    Con *ws = con_get_workspace(focused);
+    Con *next = TAILQ_NEXT(ws, nodes);
+    if (!next)
+        next = TAILQ_FIRST(&(ws->parent->nodes_head));
+
+    workspace_show(next->name);
+}
+
+/*
+ * Focuses the previous workspace.
+ *
+ */
+void workspace_prev() {
+    Con *ws = con_get_workspace(focused);
+    Con *prev = TAILQ_PREV(ws, nodes_head, nodes);
+    if (!prev)
+        prev = TAILQ_LAST(&(ws->parent->nodes_head), nodes_head);
+
+    workspace_show(prev->name);
+}
+
 static bool get_urgency_flag(Con *con) {
     Con *child;
     TAILQ_FOREACH(child, &(con->nodes_head), nodes)