highlight: add highlightfiles config option which takes a fileset (issue3005) Highlight extension lacked a way to limit files by size, by extension, and/or by any other part of file path. A good solution would be to use a fileset, since it can check file path, extension and size (and more) in one expression. So this change introduces such an option, highlighfiles, which takes a fileset and on each request decides if the requested file should be highlighted. The default "size('<5M')" is, in a way, suggested in issue3005. checkfctx() limits the amount of work to just one file (subset kwarg in fileset.matchctx()). Monkey-patching works around issue4568, otherwise using filesets here while running hgweb in directory mode would say, for example, "Abort: **.py not under root", but this fix is very local and probably far from ideal. I suspect there to be a way to fix this for the whole hgweb and resolve the issue, but I don't know how to do it.

--- a/tests/test-highlight.t	Fri Sep 04 11:15:02 2015 -0400
+++ b/tests/test-highlight.t	Wed Sep 16 22:30:36 2015 +0800
@@ -5,6 +5,7 @@
   > highlight =
   > [web]
   > pygments_style = friendly
+  > highlightfiles = **.py and size('<100KB')
   > EOF
   $ hg init test
   $ cd test
@@ -590,6 +591,28 @@
 errors encountered
 
   $ cat errors.log
+  $ killdaemons.py
+
+only highlight C source files
+
+  $ cat > .hg/hgrc <<EOF
+  > [web]
+  > highlightfiles = **.c
+  > EOF
+
+hg serve again
+
+  $ hg serve -p $HGPORT -d -n test --pid-file=hg.pid -A access.log -E errors.log
+  $ cat hg.pid >> $DAEMON_PIDS
+
+test that fileset in highlightfiles works and primes.py is not highlighted
+
+  $ get-with-headers.py localhost:$HGPORT 'file/tip/primes.py' | grep 'id="l11"'
+  <span id="l11">def primes():</span><a href="#l11"></a>
+
+errors encountered
+
+  $ cat errors.log
   $ cd ..
   $ hg init eucjp
   $ cd eucjp