fixes #570

Author: jph00

fastcore/_modidx.py

@@ -563,6 +563,7 @@
                               'fastcore.xml.XT.children': ('xml.html#xt.children', 'fastcore/xml.py'),
                               'fastcore.xml.XT.tag': ('xml.html#xt.tag', 'fastcore/xml.py'),
                               'fastcore.xml._attrmap': ('xml.html#_attrmap', 'fastcore/xml.py'),
+                              'fastcore.xml._escape': ('xml.html#_escape', 'fastcore/xml.py'),
                               'fastcore.xml._to_attr': ('xml.html#_to_attr', 'fastcore/xml.py'),
                               'fastcore.xml.highlight': ('xml.html#highlight', 'fastcore/xml.py'),
                               'fastcore.xml.showtags': ('xml.html#showtags', 'fastcore/xml.py'),

fastcore/xml.py

@@ -58,21 +58,23 @@ def xt(tag:str, *c, **kw):
 voids = set('area base br col command embed hr img input keygen link meta param source track wbr !doctype'.split())
 
 # %% ../nbs/11_xml.ipynb 13
+def _escape(s): return '' if s is None else escape(s) if isinstance(s, str) else s
+
+# %% ../nbs/11_xml.ipynb 14
 def _to_attr(k,v):
     if isinstance(v,bool):
         if v==True : return str(k)
         if v==False: return ''
-    return f'{k}="{escape(str(v), quote=False)}"'
+    return f'{k}="{escape(str(v), quote=True)}"'
 
-# %% ../nbs/11_xml.ipynb 14
+# %% ../nbs/11_xml.ipynb 15
 def to_xml(elm, lvl=0):
     "Convert `xt` element tree into an XML string"
+    if elm is None: return ''
     if isinstance(elm, tuple): return '\n'.join(to_xml(o) for o in elm)
     if hasattr(elm, '__xt__'): elm = elm.__xt__()
     sp = ' ' * lvl
-    if not isinstance(elm, list):
-        if isinstance(elm, str): elm = escape(elm)
-        return f'{elm}\n'
+    if not isinstance(elm, list): return f'{_escape(elm)}\n'
 
     tag,cs,attrs = elm
     stag = tag
@@ -82,17 +84,19 @@ def to_xml(elm, lvl=0):
 
     cltag = '' if tag in voids else f'</{tag}>'
     if not cs: return f'{sp}<{stag}>{cltag}\n'
+    if len(cs)==1 and not isinstance(cs[0],(list,tuple)) and not hasattr(cs[0],'__xt__'):
+        return f'{sp}<{stag}>{_escape(cs[0])}{cltag}\n'
     res = f'{sp}<{stag}>\n'
     res += ''.join(to_xml(c, lvl=lvl+2) for c in cs)
     if tag not in voids: res += f'{sp}{cltag}\n'
     return res
 
-# %% ../nbs/11_xml.ipynb 16
+# %% ../nbs/11_xml.ipynb 17
 def highlight(s, lang='xml'):
     "Markdown to syntax-highlight `s` in language `lang`"
     return f'```{lang}\n{to_xml(s)}\n```'
 
-# %% ../nbs/11_xml.ipynb 17
+# %% ../nbs/11_xml.ipynb 18
 def showtags(s):
     return f"""<code><pre>
 {escape(to_xml(s))}

nbs/11_xml.ipynb

@@ -202,7 +202,18 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "e89496fb",
+   "id": "254c8ff3",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#| export\n",
+    "def _escape(s): return '' if s is None else escape(s) if isinstance(s, str) else s"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "0255b96f",
    "metadata": {},
    "outputs": [],
    "source": [
@@ -211,7 +222,7 @@
     "    if isinstance(v,bool):\n",
     "        if v==True : return str(k)\n",
     "        if v==False: return ''\n",
-    "    return f'{k}=\"{escape(str(v), quote=False)}\"'"
+    "    return f'{k}=\"{escape(str(v), quote=True)}\"'"
    ]
   },
   {
@@ -224,12 +235,11 @@
     "#| export\n",
     "def to_xml(elm, lvl=0):\n",
     "    \"Convert `xt` element tree into an XML string\"\n",
+    "    if elm is None: return ''\n",
     "    if isinstance(elm, tuple): return '\\n'.join(to_xml(o) for o in elm)\n",
     "    if hasattr(elm, '__xt__'): elm = elm.__xt__()\n",
     "    sp = ' ' * lvl\n",
-    "    if not isinstance(elm, list):\n",
-    "        if isinstance(elm, str): elm = escape(elm)\n",
-    "        return f'{elm}\\n'\n",
+    "    if not isinstance(elm, list): return f'{_escape(elm)}\\n'\n",
     "\n",
     "    tag,cs,attrs = elm\n",
     "    stag = tag\n",
@@ -239,6 +249,8 @@
     "\n",
     "    cltag = '' if tag in voids else f'</{tag}>'\n",
     "    if not cs: return f'{sp}<{stag}>{cltag}\\n'\n",
+    "    if len(cs)==1 and not isinstance(cs[0],(list,tuple)) and not hasattr(cs[0],'__xt__'):\n",
+    "        return f'{sp}<{stag}>{_escape(cs[0])}{cltag}\\n'\n",
     "    res = f'{sp}<{stag}>\\n'\n",
     "    res += ''.join(to_xml(c, lvl=lvl+2) for c in cs)\n",
     "    if tag not in voids: res += f'{sp}{cltag}\\n'\n",
@@ -257,9 +269,7 @@
      "text": [
       "<html>\n",
       "  <head>\n",
-      "    <title>\n",
-      "Some page\n",
-      "    </title>\n",
+      "    <title>Some page</title>\n",
       "  </head>\n",
       "  <body>\n",
       "    <div class=\"myclass\">\n",