bolt-gen: add compilation tests

Add a test for checking that the bolt-gens do the right thing
for a fairly exhaustive test case set (and that it compiles).

Note that this doesn't check that we've got the memory assignment
pieces worked out.

It's got a kind of exotic reliance on the update-mocks in that in
order to depend on as little of the wire/ code as possible (we
only import wire/wire.h), we include an AUTOGENERATE comment
in the test_cases CSV file, and then run update-mocks as part of
the build for that file.

tools/test/Makefile

@@ -0,0 +1,40 @@
+#! /usr/bin/make
+#
+# Rudimentary tests for the wire parsers, using a set of test
+# definitions. (Covers more of the test definitions)
+#
+# We generate the files, and then we attempt to compile
+# and run a test case.
+check-units: check-tools
+
+TOOL_GEN_SRC := tools/test/gen_test.c
+TOOL_GEN_HEADER := tools/test/gen_test.h
+TOOL_TEST_SRC := $(wildcard tools/test/run-*.c)
+TOOL_TEST_OBJS := $(TOOL_TEST_SRC:.c=.o)
+TOOL_TEST_PROGRAMS := $(TOOL_TEST_OBJS:.o=)
+
+TOOL_TEST_COMMON_OBJS :=		\
+	common/utils.o
+
+TOOLS_WIRE_DEPS := $(BOLT_DEPS) tools/test/test_cases $(wildcard tools/gen/*_template)
+
+$(TOOL_TEST_SRC): $(TOOL_GEN_HEADER)
+$(TOOL_TEST_OBJS): $(TOOL_GEN_SRC)
+$(TOOL_TEST_PROGRAMS): $(TOOL_TEST_COMMON_OBJS)
+$(TOOL_GEN_SRC) $(TOOL_GEN_HEADER): $(TOOLS_WIRE_DEPS)
+
+tools/test/gen_test.h:
+	tools/generate-bolts.py --page header $@ test_type < tools/test/test_cases > $@
+
+tools/test/gen_test.c:
+	tools/generate-bolts.py --page impl ${@:.c=.h} test_type < tools/test/test_cases > $@
+	@tools/update-mocks.sh "$@"
+
+ALL_TEST_PROGRAMS += $(TOOL_TEST_PROGRAMS)
+
+check-tools: $(TOOL_TEST_PROGRAMS:%=unittest/%)
+
+clean: tools-test-clean
+
+tools-test-clean:
+	$(RM) $(TOOL_GEN_FILES) $(TOOL_TEST_OBJS)