hgweb: use our new request object for "style" parameter

hgweb: use our new request object for "style" parameter

The "style" parameter is kind of wonky because it is explicitly
set and has lookups in random locations.

Let's port it to qsparams first because it isn't straightforward.

There is subtle change in behavior. But I don't think it is worth
calling out in a BC.

Our multidict's __getitem__ returns the last set value for a key,
not the first. So if the query string set a variable multiple times,
before we would get the first value and now we would get the last
value. It makes no sense to specify these things multiple times.
And I think last write wins is more sensible than first write wins.

Differential Revision: https://phab.mercurial-scm.org/D2779

--- a/mercurial/hgweb/hgweb_mod.py	Sat Mar 10 12:35:38 2018 -0800
+++ b/mercurial/hgweb/hgweb_mod.py	Sat Mar 10 11:46:52 2018 -0800
@@ -53,9 +53,8 @@
 ))
 
 def getstyle(req, configfn, templatepath):
-    fromreq = req.form.get('style', [None])[0]
     styles = (
-        fromreq,
+        req.qsparams.get('style', None),
         configfn('web', 'style'),
         'paper',
     )
@@ -160,7 +159,7 @@
         # figure out which style to use
 
         vars = {}
-        styles, (style, mapfile) = getstyle(wsgireq, self.config,
+        styles, (style, mapfile) = getstyle(wsgireq.req, self.config,
                                             self.templatepath)
         if style == styles[0]:
             vars['style'] = style
@@ -337,7 +336,7 @@
             cmd = args.pop(0)
             style = cmd.rfind('-')
             if style != -1:
-                wsgireq.form['style'] = [cmd[:style]]
+                req.qsparams['style'] = cmd[:style]
                 cmd = cmd[style + 1:]
 
             # avoid accepting e.g. style parameter as command
@@ -355,7 +354,7 @@
 
             ua = req.headers.get('User-Agent', '')
             if cmd == 'rev' and 'mercurial' in ua:
-                wsgireq.form['style'] = ['raw']
+                req.qsparams['style'] = 'raw'
 
             if cmd == 'archive':
                 fn = wsgireq.form['node'][0]
@@ -389,7 +388,7 @@
             if cmd not in webcommands.__all__:
                 msg = 'no such method: %s' % cmd
                 raise ErrorResponse(HTTP_BAD_REQUEST, msg)
-            elif cmd == 'file' and 'raw' in wsgireq.form.get('style', []):
+            elif cmd == 'file' and req.qsparams.get('style') == 'raw':
                 rctx.ctype = ctype
                 content = webcommands.rawfile(rctx, wsgireq, tmpl)
             else:

--- a/mercurial/hgweb/hgwebdir_mod.py	Sat Mar 10 12:35:38 2018 -0800
+++ b/mercurial/hgweb/hgwebdir_mod.py	Sat Mar 10 11:46:52 2018 -0800
@@ -510,7 +510,7 @@
             url += '/'
 
         vars = {}
-        styles, (style, mapfile) = hgweb_mod.getstyle(wsgireq, config,
+        styles, (style, mapfile) = hgweb_mod.getstyle(wsgireq.req, config,
                                                       self.templatepath)
         if style == styles[0]:
             vars['style'] = style

--- a/mercurial/hgweb/webcommands.py	Sat Mar 10 12:35:38 2018 -0800
+++ b/mercurial/hgweb/webcommands.py	Sat Mar 10 11:46:52 2018 -0800
@@ -762,8 +762,8 @@
     basectx = ctx.p1()
 
     style = web.config('web', 'style')
-    if 'style' in req.form:
-        style = req.form['style'][0]
+    if 'style' in req.req.qsparams:
+        style = req.req.qsparams['style']
 
     diffs = webutil.diffs(web, tmpl, ctx, basectx, [path], style)
     if fctx is not None:
@@ -1011,8 +1011,8 @@
     entries = []
 
     diffstyle = web.config('web', 'style')
-    if 'style' in req.form:
-        diffstyle = req.form['style'][0]
+    if 'style' in req.req.qsparams:
+        diffstyle = req.req.qsparams['style']
 
     def diff(fctx, linerange=None):
         ctx = fctx.changectx()

--- a/mercurial/hgweb/webutil.py	Sat Mar 10 12:35:38 2018 -0800
+++ b/mercurial/hgweb/webutil.py	Sat Mar 10 11:46:52 2018 -0800
@@ -438,8 +438,8 @@
         basectx = ctx.p1()
 
     style = web.config('web', 'style')
-    if 'style' in req.form:
-        style = req.form['style'][0]
+    if 'style' in req.req.qsparams:
+        style = req.req.qsparams['style']
 
     diff = diffs(web, tmpl, ctx, basectx, None, style)