Bug 731779: Integrate the Add-on SDK loader and API libraries into Firefox (uplifting from addon-sdk a16bbd5772880b578a939eeb65102bca6560d494)

addon-sdk/source/python-lib/markdown/etree_loader.py

@@ -0,0 +1,33 @@
+
+from markdown import message, CRITICAL
+import sys
+
+## Import
+def importETree():
+    """Import the best implementation of ElementTree, return a module object."""
+    etree_in_c = None
+    try: # Is it Python 2.5+ with C implemenation of ElementTree installed?
+        import xml.etree.cElementTree as etree_in_c
+    except ImportError:
+        try: # Is it Python 2.5+ with Python implementation of ElementTree?
+            import xml.etree.ElementTree as etree
+        except ImportError:
+            try: # An earlier version of Python with cElementTree installed?
+                import cElementTree as etree_in_c
+            except ImportError:
+                try: # An earlier version of Python with Python ElementTree?
+                    import elementtree.ElementTree as etree
+                except ImportError:
+                    message(CRITICAL, "Failed to import ElementTree")
+                    sys.exit(1)
+    if etree_in_c and etree_in_c.VERSION < "1.0":
+        message(CRITICAL, "For cElementTree version 1.0 or higher is required.")
+        sys.exit(1)
+    elif etree_in_c :
+        return etree_in_c
+    elif etree.VERSION < "1.1":
+        message(CRITICAL, "For ElementTree version 1.1 or higher is required")
+        sys.exit(1)
+    else :
+        return etree
+