Wait for :HackerNews command to load python code Fixes #22

Once you import a python module into an instance of vim it does not get
reloaded when a plugin manager updates the plugin. This can cause errors
when, for example, a new function is added to the python module and
updated vim code is trying to call it. This commit does two things:
1) Does not load the python code until the :HackerNews command is
called. There is no need to load the python code during vim startup if
the plugin will not be used.
2) Each time the :HackerNews command is issued and a .hackernews buffer
is opened the python code is reloaded to avoid the errors previously
mentioned.

3 files changed, 36 insertions, 28 deletions

diff --git a/plugin/hackernews.py b/ftplugin/hackernews.py
index 0810b9f..78fcff0 100644
--- a/plugin/hackernews.py
+++ b/ftplugin/hackernews.py
@@ -45,13 +45,13 @@ def bwrite(s):
         b.append(s)
 
 
-def hacker_news():
+def main():
     vim.command("edit .hackernews")
     vim.command("setlocal noswapfile")
     vim.command("setlocal buftype=nofile")
 
     bwrite("┌───┐")
-    bwrite("│ Y │ Hacker News (news.ycombinator.com)")
+    bwrite("│ Y │ Hacker New (news.ycombinator.com)")
     bwrite("└───┘")
     bwrite("")
 
@@ -89,7 +89,7 @@ def hacker_news():
         bwrite("")
 
 
-def hacker_news_link(external=False):
+def link(external=False):
     line = vim.current.line
 
     # Search for Hacker News [item id]
@@ -111,7 +111,7 @@ def hacker_news_link(external=False):
             return
 
         save_pos()
-        vim.command("edit .hackernews")
+        del vim.current.buffer[:]
         if 'domain' in item:
             bwrite("%s (%s)" % (item['title'], item['domain']))
         else:
@@ -169,7 +169,7 @@ def hacker_news_link(external=False):
                 print "HackerNews.vim Error: HTTP Request Timeout"
                 return
             save_pos()
-            vim.command("edit .hackernews")
+            del vim.current.buffer[:]
             if 'domain' in item:
                 bwrite("%s (%s)" % (item['title'], item['domain']))
             else:
@@ -203,7 +203,7 @@ def hacker_news_link(external=False):
             print "HackerNews.vim Error: HTTP Request Timeout"
             return
         save_pos()
-        vim.command("edit .hackernews")
+        del vim.current.buffer[:]
         for i, line in enumerate(content.split('\n')):
             if not line:
                 bwrite("")
diff --git a/ftplugin/hackernews.vim b/ftplugin/hackernews.vim
index b5d9372..023ac99 100644
--- a/ftplugin/hackernews.vim
+++ b/ftplugin/hackernews.vim
@@ -8,12 +8,34 @@
 "  Version: 0.1.1
 
 
+if !has('python')
+    echo "HackerNews.vim Error: Requires Vim compiled with +python"
+    finish
+endif
+
 if !exists("g:hackernews_marks")
     let g:hackernews_marks = {}
 endif
 
 
-noremap <buffer> o :python hacker_news_link()<cr>
-noremap <buffer> O :python hacker_news_link(external=True)<cr>
-noremap <buffer> u u:python recall_pos()<cr>
-noremap <buffer> <C-r> <C-r>:python recall_pos()<cr>
+" Import Python code
+execute "python import sys"
+execute "python sys.path.append(r'" . expand("<sfile>:p:h") . "')"
+
+python << EOF
+if 'hackernews' not in sys.modules:
+    import hackernews
+else:
+    # Reload python module to avoid errors when updating plugin
+    hackernews = reload(hackernews)
+EOF
+
+
+" Load front page
+execute "python hackernews.main()"
+
+
+noremap <buffer> o :python hackernews.link()<cr>
+noremap <buffer> O :python hackernews.link(external=True)<cr>
+noremap <buffer> u u:python hackernews.recall_pos()<cr>
+noremap <buffer> <C-r> <C-r>:python hackernews.recall_pos()<cr>
diff --git a/plugin/hackernews.vim b/plugin/hackernews.vim
index d3a6dd7..7c8fab0 100644
--- a/plugin/hackernews.vim
+++ b/plugin/hackernews.vim
@@ -8,24 +8,10 @@
 "  Version: 0.1.1
 
 
-if !has('python')
-    echo "HackerNews.vim Error: Requires Vim compiled with +python"
-    finish
-endif
-
-
-" Filetype plugins and syntax highlighting should be enabled
+" Filetype plugins need to be enabled
 filetype plugin on
-syntax on
-
-
-" Import Python code
-execute "python import sys"
-execute "python sys.path.append(r'" . expand("<sfile>:p:h") . "')"
-execute "python from hackernews import hacker_news, hacker_news_link, recall_pos"
-
-
-command! HackerNews python hacker_news()
-
 
+" Load ftplugin when opening .hackernews buffer
 au! BufRead,BufNewFile *.hackernews set filetype=hackernews
+
+command! HackerNews edit .hackernews