Add a Dockerfile to simplify testing

Tests can be run via docker by calling

    make docker-test-image && make docker-test

Author: tarleb

.tools/Dockerfile

@@ -0,0 +1,58 @@
+FROM pandoc/latex:latest as matplotlib-builder
+RUN apk --no-cache add \
+        alpine-sdk \
+        freetype-dev \
+        libpng \
+        libpng-dev \
+        pkgconf \
+        python3 \
+        python3-dev
+RUN pip3 install matplotlib
+
+FROM pandoc/latex:latest
+RUN apk --no-cache add \
+        aspell \
+        aspell-en \
+        aspell-fr \
+        bash \
+        fontconfig \
+        graphviz \
+        inkscape \
+        libpng \
+        make \
+        openjdk8-jre \
+        python \
+        python3 \
+        ttf-dejavu \
+        wget
+
+RUN tlmgr install \
+        adjustbox \
+        bibexport \
+        changes \
+        collectbox \
+        ifmtarg \
+        silence \
+        standalone \
+        todonotes \
+        truncate \
+        xifthen \
+        xstring
+
+COPY --from=matplotlib-builder \
+  /usr/lib/python3.6/site-packages/ \
+  /usr/lib/python3.6/site-packages/
+
+# Download plantuml.jar for plantuml filter
+ARG plantuml_filename="plantuml.1.2018.9.jar"
+RUN cd $HOME && \
+    wget --quiet https://sourceforge.net/projects/plantuml/files/$plantuml_filename && \
+    cd -
+
+ENV PLANTUML "/root/$plantuml_filename"
+ENV DIFF "diff -u"
+
+# Override entrypoint set in parent image (defaults to "/usr/bin/pandoc"). This
+# image should behave like a base image.
+ENTRYPOINT []
+CMD [ "/bin/sh" ]

Makefile

@@ -1,5 +1,14 @@
 FILTERS=$(wildcard $(shell find * -type d | grep -v '[/\\]'))
-.PHONY: test
+LUA_FILTERS_TEST_IMAGE = pandoc/lua-filters-test
+
+.PHONY: test docker-test docker-test-image
 
 test:
 	bash runtests.sh $(FILTERS)
+
+docker-test:
+	docker run --rm --volume "$(PWD):/data" $(LUA_FILTERS_TEST_IMAGE) \
+	    make test
+
+docker-test-image: .tools/Dockerfile
+	docker build --tag $(LUA_FILTERS_TEST_IMAGE) --file $< .