meson: add testsuite Makefile generator

Rules to execute tests are generated by a simple Python program
that integrates into the existing "make check" mechanism.  This
provides familiarity for developers, and also allows piecewise
conversion of the testsuite Makefiles to meson.

The generated rules are based on QEMU's existing test harness
Makefile and TAP parser.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Makefile

@@ -68,6 +68,14 @@ Makefile.ninja: build.ninja ninjatool
 
 ${ninja-targets-c_COMPILER} ${ninja-targets-cpp_COMPILER}: .var.command += -MP
 
+# If MESON is empty, the rule will be re-evaluated after Makefiles are
+# reread (and MESON won't be empty anymore).
+ifneq ($(MESON),)
+Makefile.mtest: build.ninja scripts/mtest2make.py
+	$(MESON) introspect --tests | $(PYTHON) scripts/mtest2make.py > $@
+-include Makefile.mtest
+endif
+
 .git-submodule-status: git-submodule-update config-host.mak
 
 # Check that we're not trying to do an out-of-tree build from
@@ -825,7 +833,7 @@ distclean: clean ninja-distclean
 	rm -f roms/seabios/config.mak roms/vgabios/config.mak
 	rm -f qemu-plugins-ld.symbols qemu-plugins-ld64.symbols
 	rm -rf meson-private meson-logs meson-info compile_commands.json
-	rm -f Makefile.ninja ninjatool ninjatool.stamp
+	rm -f Makefile.ninja ninjatool ninjatool.stamp Makefile.mtest
 	rm -f config.log
 	rm -f linux-headers/asm
 	rm -f docs/version.texi

scripts/mtest2make.py

@@ -0,0 +1,102 @@
+#! /usr/bin/env python3
+
+# Create Makefile targets to run tests, from Meson's test introspection data.
+#
+# Author: Paolo Bonzini <pbonzini@redhat.com>
+
+from collections import defaultdict
+import json
+import os
+import shlex
+import sys
+
+class Suite(object):
+    def __init__(self):
+        self.tests = list()
+        self.slow_tests = list()
+        self.executables = set()
+
+print('''
+SPEED = quick
+
+# $1 = test command, $2 = test name
+.test-human-tap = $1 < /dev/null | ./scripts/tap-driver.pl --test-name="$2" $(if $(V),,--show-failures-only)
+.test-human-exitcode = $1 < /dev/null
+.test-tap-tap = $1 < /dev/null | sed "s/^[a-z][a-z]* [0-9]*/& $2/" || true
+.test-tap-exitcode = printf "%s\\n" 1..1 "`$1 < /dev/null > /dev/null || echo "not "`ok 1 $2"
+.test.print = echo $(if $(V),'$1','Running test $2') >&3
+.test.env = MALLOC_PERTURB_=$${MALLOC_PERTURB_:-$$(( $${RANDOM:-0} % 255 + 1))}
+
+# $1 = test name, $2 = test target (human or tap)
+.test.run = $(call .test.print,$(.test.cmd.$1),$(.test.name.$1)) && $(call .test-$2-$(.test.driver.$1),$(.test.cmd.$1),$(.test.name.$1))
+
+define .test.human_k
+        @exec 3>&1; rc=0; $(foreach TEST, $1, $(call .test.run,$(TEST),human) || rc=$$?;) \\
+              exit $$rc
+endef
+define .test.human_no_k
+        $(foreach TEST, $1, @exec 3>&1; $(call .test.run,$(TEST),human)
+)
+endef
+.test.human = \\
+        $(if $(findstring k, $(MAKEFLAGS)), $(.test.human_k), $(.test.human_no_k))
+
+define .test.tap
+        @exec 3>&1; { $(foreach TEST, $1, $(call .test.run,$(TEST),tap); ) } \\
+              | ./scripts/tap-merge.pl | tee "$@" \\
+              | ./scripts/tap-driver.pl $(if $(V),, --show-failures-only)
+endef
+''')
+
+suites = defaultdict(Suite)
+i = 0
+for test in json.load(sys.stdin):
+    env = ' '.join(('%s=%s' % (shlex.quote(k), shlex.quote(v))
+                    for k, v in test['env'].items()))
+    executable = os.path.relpath(test['cmd'][0])
+    if test['workdir'] is not None:
+        test['cmd'][0] = os.path.relpath(test['cmd'][0], test['workdir'])
+    else:
+        test['cmd'][0] = executable
+    cmd = '$(.test.env) %s %s' % (env, ' '.join((shlex.quote(x) for x in test['cmd'])))
+    if test['workdir'] is not None:
+        cmd = '(cd %s && %s)' % (shlex.quote(test['workdir']), cmd)
+    driver = test['protocol'] if 'protocol' in test else 'exitcode'
+
+    i += 1
+    print('.test.name.%d := %s' % (i, test['name']))
+    print('.test.driver.%d := %s' % (i, driver))
+    print('.test.cmd.%d := %s' % (i, cmd))
+
+    test_suites = test['suite'] or ['default']
+    is_slow = any(s.endswith('-slow') for s in test_suites)
+    for s in test_suites:
+        # The suite name in the introspection info is "PROJECT:SUITE"
+        s = s.split(':')[1]
+        if s.endswith('-slow'):
+            s = s[:-5]
+        if is_slow:
+            suites[s].slow_tests.append(i)
+        else:
+            suites[s].tests.append(i)
+        suites[s].executables.add(executable)
+
+print('.PHONY: check check-report.tap')
+print('check:')
+print('check-report.tap:')
+print('\t@cat $^ | scripts/tap-merge.pl >$@')
+for name, suite in suites.items():
+    executables = ' '.join(suite.executables)
+    slow_test_numbers = ' '.join((str(x) for x in suite.slow_tests))
+    test_numbers = ' '.join((str(x) for x in suite.tests))
+    print('.test.suite-quick.%s := %s' % (name, test_numbers))
+    print('.test.suite-slow.%s := $(.test.suite-quick.%s) %s' % (name, name, slow_test_numbers))
+    print('check-build: %s' % executables)
+    print('.PHONY: check-%s' % name)
+    print('.PHONY: check-report-%s.tap' % name)
+    print('check: check-%s' % name)
+    print('check-%s: all %s' % (name, executables))
+    print('\t$(call .test.human, $(.test.suite-$(SPEED).%s))' % (name, ))
+    print('check-report.tap: check-report-%s.tap' % name)
+    print('check-report-%s.tap: %s' % (name, executables))
+    print('\t$(call .test.tap, $(.test.suite-$(SPEED).%s))' % (name, ))

tests/Makefile.include

@@ -674,7 +674,6 @@ check-report-unit.tap: $(check-unit-y)
 # Reports and overall runs
 
 check-report.tap: $(patsubst %,check-report-qtest-%.tap, $(QTEST_TARGETS)) check-report-unit.tap
-	$(call quiet-command, cat $^ | scripts/tap-merge.pl >$@,"GEN","$@")
 
 # FPU Emulation tests (aka softfloat)
 #