From 719441cca5a237bde4bbfd01e70bd6ecb7021d30 Mon Sep 17 00:00:00 2001
From: Bastian Kleineidam <calvin@debian.org>
Date: Wed, 20 Apr 2011 09:08:11 +0200
Subject: [PATCH] Make module detection more robust and use it when possible.

---
 doc/changelog.txt                   | 4 ++++
 linkcheck/checker/urlbase.py        | 5 ++---
 linkcheck/configuration/__init__.py | 8 ++------
 linkcheck/fileutil.py               | 3 ++-
 4 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/doc/changelog.txt b/doc/changelog.txt
index 99d40b77..b65c8842 100644
--- a/doc/changelog.txt
+++ b/doc/changelog.txt
@@ -1,5 +1,9 @@
 6.8 "" (released xx.xx.2011)
 
+Fixes:
+- checking: make module detection more robust
+
+
 Changes:
 - gui: Print detected module information in about dialog.
 - gui: Close application on Ctrl-C.
diff --git a/linkcheck/checker/urlbase.py b/linkcheck/checker/urlbase.py
index 159675d4..bb8b24c2 100644
--- a/linkcheck/checker/urlbase.py
+++ b/linkcheck/checker/urlbase.py
@@ -754,12 +754,11 @@ class UrlBase (object):
     def check_html (self):
         """Check HTML syntax of this page (which is supposed to be HTML)
         with the local HTML tidy module."""
-        try:
-            import tidy
-        except ImportError:
+        if not fileutil.has_module("tidy"):
             log.warn(LOG_CHECK, _("warning: tidy module is not available; " \
                  "download from http://utidylib.berlios.de/"))
             return
+        import tidy
         options = dict(output_html=0, show_warnings=1, quiet=True,
             input_encoding='utf8', output_encoding='utf8', tidy_mark=0)
         try:
diff --git a/linkcheck/configuration/__init__.py b/linkcheck/configuration/__init__.py
index f7c568b5..d49d3f19 100644
--- a/linkcheck/configuration/__init__.py
+++ b/linkcheck/configuration/__init__.py
@@ -339,9 +339,7 @@ class Configuration (dict):
 
     def sanitize_checkhtml (self):
         """Ensure HTML tidy is installed for checking HTML."""
-        try:
-            import tidy
-        except ImportError:
+        if not fileutil.has_module("tidy"):
             log.warn(LOG_CHECK,
                 _("warning: tidy module is not available; " \
                  "download from http://utidylib.berlios.de/"))
@@ -349,9 +347,7 @@ class Configuration (dict):
 
     def sanitize_checkcss (self):
         """Ensure cssutils is installed for checking CSS."""
-        try:
-            import cssutils
-        except ImportError:
+        if not fileutil.has_module("cssutils"):
             log.warn(LOG_CHECK,
                 _("warning: cssutils module is not available; " \
                  "download from http://cthedot.de/cssutils/"))
diff --git a/linkcheck/fileutil.py b/linkcheck/fileutil.py
index 60cd8afa..e70321d6 100644
--- a/linkcheck/fileutil.py
+++ b/linkcheck/fileutil.py
@@ -65,7 +65,8 @@ def has_module (name):
     try:
         exec "import %s" % name
         return True
-    except ImportError:
+    except (OSError, ImportError):
+        # some modules (for example HTMLtidy) raise OSError
         return False