From 001b57bc5108644dd351d63ec8c8cc561773fa9e Mon Sep 17 00:00:00 2001
From: "W. Trevor King" <wking@tremily.us>
Date: Mon, 25 Feb 2013 21:51:19 -0500
Subject: [PATCH] swc-installation-test-2.py: Add support for package-specific
 URLs

To give users more targeted advice for fixing their installation
problems, we should link them to somewhere more specific than the root
SWC setup page.  The two knobs in the specific URL are system/OS
(Gentoo, Debian, OS X, MS Windows, ...) and package (the dependency
name: emacs, git, virtual-browser, ...).  We don't have consistent
URLs upstream yet [1], but maybe this commit will help motivate them
;).

[1]: https://github.com/swcarpentry/website/issues/2
---
 setup/swc-installation-test-2.py | 26 +++++++++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/setup/swc-installation-test-2.py b/setup/swc-installation-test-2.py
index b2a116b..7269b73 100755
--- a/setup/swc-installation-test-2.py
+++ b/setup/swc-installation-test-2.py
@@ -45,6 +45,10 @@ import re as _re
 import shlex as _shlex
 import subprocess as _subprocess
 import sys as _sys
+try:  # Python 3.x
+    import urllib.parse as _urllib_parse
+except ImportError:  # Python 2.x
+    import urllib as _urllib_parse  # for quote()
 
 
 if not hasattr(_shlex, 'quote'):  # Python versions older than 3.3
@@ -107,6 +111,12 @@ class InvalidCheck (KeyError):
 
 
 class DependencyError (Exception):
+    _system_map = {  # map long system names to shorter forms
+        'Gentoo Base System': 'Gentoo',
+        }
+    _supported = [  # (system, package) pairs with specific instructions
+        ]
+
     def _get_message(self):
         return self._message
     def _set_message(self, message):
@@ -121,8 +131,22 @@ class DependencyError (Exception):
             causes = []
         self.causes = causes
 
+    def get_url(self):
+        url = 'http://software-carpentry.org/setup/'
+        system = _platform.system()
+        if system == 'Linux':
+            system = _platform.linux_distribution()[0] or system
+        system = self._system_map.get(system, system)
+        package = self.checker.name
+        if (system, package) in self._supported:
+            url = '{0}{1}.html#{2}'.format(
+                url,
+                _urllib_parse.quote(system.lower()),
+                _urllib_parse.quote(package))
+        return url
+
     def __str__(self):
-        url = 'http://software-carpentry.org/setup/'  # TODO: per-package URL
+        url = self.get_url()
         lines = [
             'check for {0} failed:'.format(self.checker.full_name()),
             '  ' + self.message,
-- 
2.26.2