optionally supplement roles dict by vim function source

The application was restricted to loading role configurations only from
a predefined config file, which limited extensibility.

Enable dynamic role configuration by invoking a custom Vim function if
it is defined. This allows users to extend the role configurations
beyond the static file.

diff --git a/doc/vim-ai.txt b/doc/vim-ai.txt:
-The roles in g:vim_ai_roles_config_file are converted to a Vim dictionary.
-Optionally, additional roles can be added by defining a function VimAIRoleParser()
-whose output is a dictionary of the same format as g:vim_ai_roles_config_file.
-
diff --git a/py/roles.py b/py/roles.py:
-if vim.eval('exists("*VimAIRoleParser")'):
-    roles.update(vim.eval('VimAIRoleParser()'))
-
diff --git a/py/utils.py b/py/utils.py:
-    if vim.eval('exists("*VimAIRoleParser")'):
-        roles.update(vim.eval('VimAIRoleParser()'))
-

3 files changed, 19 insertions, 0 deletions

diff --git a/doc/vim-ai.txt b/doc/vim-ai.txt
index 5d06fc7..c7aefde 100644
--- a/doc/vim-ai.txt
+++ b/doc/vim-ai.txt
@@ -177,6 +177,11 @@ Example of a role: >
 
 See roles-example.ini for more examples.
 
+The roles in g:vim_ai_roles_config_file are converted to a Vim dictionary whose
+labels are the names of the roles. Optionally, roles can be added by setting
+g:vim_ai_roles_config_function to the name of a Vimscript function returning a
+dictionary of the same format as g:vim_ai_roles_config_file.
+
 KEY BINDINGS
 
 Examples how configure key bindings and customize commands: >
diff --git a/py/roles.py b/py/roles.py
index a8689f2..6e0a52e 100644
--- a/py/roles.py
+++ b/py/roles.py
@@ -9,6 +9,13 @@ if not os.path.exists(roles_config_path):
 roles = configparser.ConfigParser()
 roles.read(roles_config_path)
 
+if vim.eval("exists('g:vim_ai_roles_config_function')") == '1':
+    roles_config_function = vim.eval("g:vim_ai_roles_config_function")
+    if not vim.eval("exists('*" + roles_config_function + "')"):
+        raise Exception(f"Role config function does not exist: {roles_config_function}")
+    else:
+        roles.update(vim.eval(roles_config_function + "()"))
+
 role_names = [name for name in roles.sections() if not '.' in name]
 
 role_list = [f'"{name}"' for name in role_names]
diff --git a/py/utils.py b/py/utils.py
index 6bd90a1..471b5c4 100644
--- a/py/utils.py
+++ b/py/utils.py
@@ -271,6 +271,13 @@ def load_role_config(role):
     roles = configparser.ConfigParser()
     roles.read(roles_config_path)
 
+    if vim.eval("exists('g:vim_ai_roles_config_function')") == '1':
+        roles_config_function = vim.eval("g:vim_ai_roles_config_function")
+        if not vim.eval("exists('*" + roles_config_function + "')"):
+            raise Exception(f"Role config function does not exist: {roles_config_function}")
+        else:
+            roles.update(vim.eval(roles_config_function + "()"))
+
     if not role in roles:
         raise Exception(f"Role `{role}` not found")