From 9c8633f0258d0750fd81387fe826d4522873cd90 Mon Sep 17 00:00:00 2001
From: Nick Bowler <nbowler@draconx.ca>
Date: Fri, 2 Mar 2012 22:30:15 -0500
Subject: [PATCH] Batch up crossparse tests to improve performance.

A significant portion of the crossparse test time is spent just starting
the program hundreds of times.  Batch up the random declarations to
reduce this.  This makes the test script somewhat more complex, but the
gain is significant: the test time (500 iterations) on my machine is
shortened from 7 seconds to a mere .7 seconds.
---
 test/crossparse.c            | 72 ++++++++++++++++++++++--------------
 tests/crossparse-c-random.sh | 41 ++++++++++++++++++--
 2 files changed, 81 insertions(+), 32 deletions(-)

diff --git a/test/crossparse.c b/test/crossparse.c
index 75344cb..f377c38 100644
--- a/test/crossparse.c
+++ b/test/crossparse.c
@@ -2,6 +2,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <stdbool.h>
 #include <getopt.h>
 #include <cdecl.h>
 #include "test.h"
@@ -69,9 +70,44 @@ err:
 }
 #define rerender(str, p, r) (rerender(str, #p, p, #r, r))
 
-int main(int argc, char **argv)
+static bool test_crossparse(const char *str, int mode)
 {
 	char *buf1 = NULL, *buf2 = NULL, *buf3 = NULL;
+	bool ret = false;
+
+	if (mode == MODE_ENGLISH) {
+		buf1 = rerender(str, cdecl_parse_english, cdecl_declare);
+		if (!buf1)
+			goto out;
+		buf2 = rerender(buf1, cdecl_parse_decl, cdecl_explain);
+		if (!buf2)
+			goto out;
+		buf3 = rerender(buf2, cdecl_parse_english, cdecl_declare);
+		if (!buf3)
+			goto out;
+	} else {
+		buf1 = rerender(str, cdecl_parse_decl, cdecl_explain);
+		if (!buf1)
+			goto out;
+		buf2 = rerender(buf1, cdecl_parse_english, cdecl_declare);
+		if (!buf2)
+			goto out;
+		buf3 = rerender(buf2, cdecl_parse_decl, cdecl_explain);
+		if (!buf3)
+			goto out;
+	}
+
+	if (!strcmp(buf1, buf3))
+		ret = true;
+out:
+	free(buf1);
+	free(buf2);
+	free(buf3);
+	return ret;
+}
+
+int main(int argc, char **argv)
+{
 	int opt, mode = MODE_CDECL;
 	int ret = EXIT_FAILURE;
 
@@ -103,33 +139,13 @@ int main(int argc, char **argv)
 		return EXIT_FAILURE;
 	}
 
-	if (mode == MODE_ENGLISH) {
-		buf1 = rerender(argv[optind], cdecl_parse_english, cdecl_declare);
-		if (!buf1)
-			goto out;
-		buf2 = rerender(buf1, cdecl_parse_decl, cdecl_explain);
-		if (!buf2)
-			goto out;
-		buf3 = rerender(buf2, cdecl_parse_english, cdecl_declare);
-		if (!buf3)
-			goto out;
-	} else {
-		buf1 = rerender(argv[optind], cdecl_parse_decl, cdecl_explain);
-		if (!buf1)
-			goto out;
-		buf2 = rerender(buf1, cdecl_parse_english, cdecl_declare);
-		if (!buf2)
-			goto out;
-		buf3 = rerender(buf2, cdecl_parse_decl, cdecl_explain);
-		if (!buf3)
-			goto out;
+	for (int i = optind; i < argc; i++) {
+		if (!test_crossparse(argv[i], mode)) {
+			fprintf(stderr, "%s: failed cross-parse check of: %s\n",
+			                progname, argv[i]);
+			return EXIT_FAILURE;
+		}
 	}
 
-	if (!strcmp(buf1, buf3))
-		ret = EXIT_SUCCESS;
-out:
-	free(buf1);
-	free(buf2);
-	free(buf3);
-	return ret;
+	return EXIT_SUCCESS;
 }
diff --git a/tests/crossparse-c-random.sh b/tests/crossparse-c-random.sh
index 8fb1b63..9fc45fb 100755
--- a/tests/crossparse-c-random.sh
+++ b/tests/crossparse-c-random.sh
@@ -14,19 +14,52 @@ randomdecl=test/randomdecl$EXEEXT
 crossparse=test/crossparse$EXEEXT
 test -x $randomdecl || exit 77
 
+# Slow case: run tests one at a time to determine exactly which one failed.
+first_failed() {
+	ff_count=0
+
+	while test $# -gt 0
+	do
+		$crossparse "$1" 2>/dev/null || break
+		ff_count=`expr $ff_count + 1`
+		shift
+	done
+
+	echo "$ff_count"
+}
+
 proc() {
 	result=pass
 	count=0
 
+	set x
 	while read decl
 	do
-		count=`expr $count + 1`
-		$crossparse "$decl" || { result=fail
-			printf 'original input: %s\n' "$decl" 1>&2
-			break
+		set "$@" "$decl"
+
+		# Accumulate tests in $@ and run them in batches to avoid
+		# significant startup costs.
+		if test $# -gt 25; then
+			shift
+			$crossparse "$@" || { result=fail
+				tmp_count=`first_failed "$@"`
+				count=`expr $count + $tmp_count`
+				break
 			}
+			count=`expr $count + $#`
+			set x
+		fi
 	done
 
+	shift
+	if test $# -gt 0 && test x"$result" = x"pass"; then
+		tmp_count=$#
+		$crossparse "$@" || { result=fail
+			tmp_count=`first_failed "$@"`
+		}
+		count=`expr $count + $tmp_count`
+	fi
+
 	echo "result=$result"
 	echo "count=$count"
 }
-- 
2.43.0