Add Makefile For Easy Automated Testing Immediately After Building

New Makefile lets testers build the static HTML files and then run a few
automated tests to catch problems like missing files and links.  The
Makefile is not required; the site can still be built using just Jekyll.

This commit also fixes several image-related errors reported by `make
test` by adding the missing PNG images.

Makefile

@@ -0,0 +1,109 @@
+## Optional Makefile: only used for testing & maintainer automation;
+##                    not used to build live site
+
+S=@  ## Silent: only print errors by default; 
+     ## run `make S='' [other args]` to print commands as they're run
+
+## Old versions of jekyll must not call "build".  If you have one of
+## these versions, either run make like this: make JEKYLL_COMMAND=jekyll
+## or create the JEKYLL_COMMAND environmental variable:
+# echo 'export JEKYLL_COMMAND=jekyll' >> ~/.bashrc
+# exec bash
+# make
+JEKYLL_COMMAND ?= "bundle exec jekyll build"
+SITEDIR=_site
+JEKYLL_LOG=._jekyll.log
+
+#######################
+## REGULAR ARGUMENTS ##
+#######################
+
+## `make` (no arguments): just build
+default: build
+
+## `make test`: don't build, but do run all tests
+test: pre-build-tests post-build-tests
+
+## `make valid`: build and run fast tests
+valid: pre-build-tests-fast build post-build-tests-fast
+
+## `make all`: build and run all tests
+all: pre-build-tests build post-build-tests
+
+
+
+## Pre-build tests which, aggregated together, take less than 5 seconds to run on a typical PC
+pre-build-tests-fast: check-for-non-ascii-urls
+
+## Post-build tests which, aggregated together, take less than 5 seconds to run on a typical PC
+post-build-tests-fast: check-for-build-errors ensure-each-svg-has-a-png check-for-liquid-errors \
+    check-for-missing-anchors check-for-broken-markdown-reference-links
+
+## All pre-build tests, including those which might take multiple minutes
+pre-build-tests: pre-build-tests-fast
+	@ true
+
+## All post-build tests, including those which might take multiple minutes
+post-build-tests: post-build-tests-fast
+	@ true ## SOMEDAY: use linkchecker to find broken links 
+	@      ## after this bug is fixed: https://github.com/wummel/linkchecker/issues/513
+
+
+
+
+
+#################
+## SUB-TARGETS ##
+#################
+ERROR_ON_OUTPUT="sed '1s/^/ERROR:\n/' | if grep . ; then sed 1iERROR ; false ; else true ; fi"
+
+## Always build using the default locale so log messages can be grepped.
+## This should not affect webpage output.
+build:
+	$S export LANG=C.UTF-8 ; eval $(JEKYLL_COMMAND) 2>&1 | tee $(JEKYLL_LOG)
+
+
+## Jekyll annoyingly returns success even when it emits errors and
+## exceptions, so we'll grep its output for error strings
+check-for-build-errors:
+	$S egrep -i '(error|warn|exception)' $(JEKYLL_LOG) \
+	    | eval $(ERROR_ON_OUTPUT)
+
+
+## Old browser support requires each SVG image also be available as a
+## PNG with the same base name
+ensure-each-svg-has-a-png:
+	$S find $(SITEDIR)/img -name '*.svg' | while read file \
+	    ; do test -f $${file%.svg}.png || echo "$$file missing corresponding PNG" \
+	; done | eval $(ERROR_ON_OUTPUT)
+
+	
+## Some Jekyll errors leave error messages in the text
+check-for-liquid-errors:
+	$S grep -r 'Liquid syntax error:' $(SITEDIR)/ | eval $(ERROR_ON_OUTPUT)
+
+
+## Report missing anchors for local links defined in the references file.
+#
+## Takes less than 1 second here as of 2014-05-16 -harding
+check-for-missing-anchors:
+	$S sed -n 's!^\[[^]]*]: \+!!; s/ .*//; /#/s!^/!!p' _includes/references.md \
+	    | sort -u \
+	    | while read link ; do file="$(SITEDIR)/$${link%#*}.html" \
+	        ; anchor="$${link##*#}" \
+	        ; egrep -ql '(id|name)=.'$$anchor'[^a-zA-Z0-9_-]' $$file \
+	        || echo "$$file#$$anchor not found" \
+	    ; done | eval $(ERROR_ON_OUTPUT)
+
+check-for-broken-markdown-reference-links:
+## Report Markdown reference-style links which weren't converted to HTML
+## links in the output, indicating there's no reference definition
+	$S find $(SITEDIR) -name '*.html' | xargs grep '\]\[' | eval $(ERROR_ON_OUTPUT)
+
+check-for-non-ascii-urls:
+## Always check all translated urls don't contain non-ASCII
+## characters or spaces.
+	$S find _translations -name '*.yml' | while read file \
+	    ; do grep -H . $$file | sed -n -e '/url:/,$$p' \
+	    | grep -P '[^\x00-\x7f]|[a-z\-] [a-z\-]' \
+	; done | eval $(ERROR_ON_OUTPUT)

README.md

@@ -95,6 +95,30 @@ from _site/ to the root of your web server. If you have no web server, run
 http://127.0.0.1:4000/. This server requires you to add a trailing ".html"
 by hand in your browser address bar.
 
+#### Building With Make
+
+After you've installed Jekyll and the other depenencies, you can
+optionally use GNU Make to automatically build the site and run several
+tests. You will first need to install Make using your package manager;
+for example:
+
+    sudo apt-get install make
+
+Then in your local bitcoin.org repository, run one of the following
+commands:
+
+    ## To just build the site, the equivalent of: bundle exec jekyll build
+    make
+
+    ## After you build the site, you can run all of the tests (may take awhile)
+    make test
+
+    ## Or you can build the site and run some quick tests with one command:
+    make valid
+
+    ## Or build the site and run all tests
+    make all
+
 ## Developer Documentation
 
 Each part of the documentation can be found in the [_includes](https://github.com/bitcoin/bitcoin.org/tree/master/_includes)

_config.yml

@@ -132,6 +132,7 @@ plugins:     ./_plugins
 exclude:
     - Gemfile
     - Gemfile.lock
+    - Makefile
 
 future:      true
 lsi:         false