[PATCH 1 of 2] highlight: configurable file size limit (issue3005)

[Anton Shestakov]

# HG changeset patch
# User Anton Shestakov <av6 at dwimlabs.net>
# Date 1438508200 -28800
#      Sun Aug 02 17:36:40 2015 +0800
# Branch stable
# Node ID 1426bfe350e2070e0fcaf7c0a083e4e385f83805
# Parent  79f0cb97d7537a7c2948f8f9b0a89148825a3a1d
highlight: configurable file size limit (issue3005)

The issue is titled: "MemoryError when using highlight in hgweb", and one of
the proposed solutions to the problem was to make a configurable limit for
highlight extension so it doesn't pygmentize files above a certain size.

Let's introduce such an option, named highlightmax and set its default to 5 MB
(this value is, again, taken from the issue). If a file is above this limit,
highlight extension skips it completely.

diff --git a/hgext/highlight/__init__.py b/hgext/highlight/__init__.py
--- a/hgext/highlight/__init__.py
+++ b/hgext/highlight/__init__.py
@@ -13,12 +13,11 @@
 It depends on the Pygments syntax highlighting library:
 http://pygments.org/
 
-There is a single configuration option::
+There are two configuration options::
 
   [web]
-  pygments_style = <style>
-
-The default is 'colorful'.
+  pygments_style = <style> (default: 'colorful')
+  highlightmax = <file size> (default: 5 MB)
 """
 
 import highlight
@@ -41,7 +40,9 @@ def filerevision_highlight(orig, web, re
     # pygmentize a html file
     if 'html' in mt:
         style = web.config('web', 'pygments_style', 'colorful')
-        highlight.pygmentize('fileline', fctx, style, tmpl)
+        maxbytes = web.configbytes('web', 'highlightmax', '5 MB')
+        if fctx.size() <= maxbytes:
+            highlight.pygmentize('fileline', fctx, style, tmpl)
     return orig(web, req, tmpl, fctx)
 
 def annotate_highlight(orig, web, req, tmpl):
@@ -49,7 +50,9 @@ def annotate_highlight(orig, web, req, t
     if 'html' in mt:
         fctx = webutil.filectx(web.repo, req)
         style = web.config('web', 'pygments_style', 'colorful')
-        highlight.pygmentize('annotateline', fctx, style, tmpl)
+        maxbytes = web.configbytes('web', 'highlightmax', '5 MB')
+        if fctx.size() <= maxbytes:
+            highlight.pygmentize('annotateline', fctx, style, tmpl)
     return orig(web, req, tmpl)
 
 def generate_css(web, req, tmpl):
diff --git a/mercurial/hgweb/hgweb_mod.py b/mercurial/hgweb/hgweb_mod.py
--- a/mercurial/hgweb/hgweb_mod.py
+++ b/mercurial/hgweb/hgweb_mod.py
@@ -104,6 +104,10 @@ class hgweb(object):
         return self.repo.ui.configbool(section, name, default,
                                        untrusted=untrusted)
 
+    def configbytes(self, section, name, default=0, untrusted=True):
+        return self.repo.ui.configbytes(section, name, default,
+                                       untrusted=untrusted)
+
     def configlist(self, section, name, default=None, untrusted=True):
         return self.repo.ui.configlist(section, name, default,
                                        untrusted=untrusted)