Whenever a test appears in multiple suites, the rules generated
by mtest2make are currently running it twice.  Instead, after
this patch we generate a phony target for each test and we have
a generic "run-tests" target depend on all the tests that were
chosen on the command line.  Tests that appear in multiple suites
will be added to the prerequisites just once.

This has other advantages: it removes the handling of -k and
it increases parallelism.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 scripts/mtest2make.py | 74 ++++++++++++++++++++++---------------------
 1 file changed, 38 insertions(+), 36 deletions(-)

diff --git a/scripts/mtest2make.py b/scripts/mtest2make.py
index 27425080cf..af6dd0d3b1 100644
--- a/scripts/mtest2make.py
+++ b/scripts/mtest2make.py
@@ -24,33 +24,20 @@ SPEED = quick
 .test-human-exitcode = $1 $(PYTHON) scripts/test-driver.py $(if $4,-C$4) $(if $(V),--verbose) -- $2 < /dev/null
 .test-tap-tap = $1 $(if $4,(cd $4 && $2),$2) < /dev/null | sed "s/^[a-z][a-z]* [0-9]*/& $3/" || true
 .test-tap-exitcode = printf "%s\\n" 1..1 "`$1 $(if $4,(cd $4 && $2),$2) < /dev/null > /dev/null || echo "not "`ok 1 $3"
-.test.print = echo $(if $(V),'$1 $2','Running test $3') >&3
+.test.human-print = echo $(if $(V),'$1 $2','Running test $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.env.$1),$(.test.cmd.$1),$(.test.name.$1)) && $(call .test-$2-$(.test.driver.$1),$(.test.env.$1),$(.test.cmd.$1),$(.test.name.$1),$(.test.dir.$1))
+.test.run = $(call .test.$2-print,$(.test.env.$1),$(.test.cmd.$1),$(.test.name.$1)) $(call .test-$2-$(.test.driver.$1),$(.test.env.$1),$(.test.cmd.$1),$(.test.name.$1),$(.test.dir.$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
+.test.output-format = human
 ''')
 
-suites = defaultdict(Suite)
+introspect = json.load(sys.stdin)
 i = 0
-for test in json.load(sys.stdin):
+
+def process_tests(test, suites):
+    global i
     env = ' '.join(('%s=%s' % (shlex.quote(k), shlex.quote(v))
                     for k, v in test['env'].items()))
     executable = test['cmd'][0]
@@ -75,6 +62,9 @@ for test in json.load(sys.stdin):
     print('.test.driver.%d := %s' % (i, driver))
     print('.test.env.%d := $(.test.env) %s' % (i, env))
     print('.test.cmd.%d := %s' % (i, cmd))
+    print('.PHONY: run-test-%d' % (i,))
+    print('run-test-%d: all' % (i,))
+    print('\t@$(call .test.run,%d,$(.test.output-format))' % (i,))
 
     test_suites = test['suite'] or ['default']
     is_slow = any(s.endswith('-slow') for s in test_suites)
@@ -89,22 +79,34 @@ for test in json.load(sys.stdin):
             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():
+def emit_prolog(suites, prefix):
+    all_tap = ' '.join(('%s-report-%s.tap' % (prefix, k) for k in suites.keys()))
+    print('.PHONY: %s %s-report.tap %s' % (prefix, prefix, all_tap))
+    print('%s: run-tests' % (prefix,))
+    print('%s-report.tap %s: %s-report%%.tap: all' % (prefix, all_tap, prefix))
+    print('''\t$(MAKE) .test.output-format=tap --quiet -Otarget V=1 %s$* | ./scripts/tap-merge.pl | tee "$@" \\
+              | ./scripts/tap-driver.pl $(if $(V),, --show-failures-only)''' % (prefix, ))
+
+def emit_suite(name, suite, prefix):
     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, ))
+    target = '%s-%s' % (prefix, name)
+    print('.test.quick.%s := %s' % (target, test_numbers))
+    print('.test.slow.%s := $(.test.quick.%s) %s' % (target, target, slow_test_numbers))
+    print('%s-build: %s' % (prefix, executables))
+    print('.PHONY: %s' % (target, ))
+    print('.PHONY: %s-report-%s.tap' % (prefix, name))
+    print('%s: run-tests' % (target, ))
+    print('ifneq ($(filter %s %s, $(MAKECMDGOALS)),)' % (target, prefix))
+    print('.tests += $(.test.$(SPEED).%s)' % (target, ))
+    print('endif')
+
+testsuites = defaultdict(Suite)
+for test in introspect:
+    process_tests(test, testsuites)
+emit_prolog(testsuites, 'check')
+for name, suite in testsuites.items():
+    emit_suite(name, suite, 'check')
+
+print('run-tests: $(patsubst %, run-test-%, $(.tests))')
-- 
2.26.2