Improve pg_regress's error reporting for schedule-file problems.

The previous coding here trashed the line buffer as it scanned it,
making it impossible to print the source line in subsequent error
messages.  With a few save/restore/strdup pushups we can improve
that situation.

In passing, move the free'ing of the various strings that are collected
while processing one set of tests down to the bottom of the loop.
That's simpler, less surprising, and should make valgrind less unhappy
about the strings that were previously leaked by the last iteration.

src/test/regress/pg_regress.c

@@ -1593,6 +1593,7 @@ run_schedule(const char *schedule, test_function tfunc)
 	FILE	   *scf;
 	int			line_num = 0;
 
+	memset(tests, 0, sizeof(tests));
 	memset(resultfiles, 0, sizeof(resultfiles));
 	memset(expectfiles, 0, sizeof(expectfiles));
 	memset(tags, 0, sizeof(tags));
@@ -1615,16 +1616,6 @@ run_schedule(const char *schedule, test_function tfunc)
 
 		line_num++;
 
-		/* clear out string lists left over from previous line */
-		for (i = 0; i < MAX_PARALLEL_TESTS; i++)
-		{
-			if (resultfiles[i] == NULL)
-				break;
-			free_stringlist(&resultfiles[i]);
-			free_stringlist(&expectfiles[i]);
-			free_stringlist(&tags[i]);
-		}
-
 		/* strip trailing whitespace, especially the newline */
 		i = strlen(scbuf);
 		while (i > 0 && isspace((unsigned char) scbuf[i - 1]))
@@ -1657,24 +1648,35 @@ run_schedule(const char *schedule, test_function tfunc)
 
 		num_tests = 0;
 		inword = false;
-		for (c = test; *c; c++)
+		for (c = test;; c++)
 		{
-			if (isspace((unsigned char) *c))
+			if (*c == '\0' || isspace((unsigned char) *c))
 			{
-				*c = '\0';
-				inword = false;
+				if (inword)
+				{
+					/* Reached end of a test name */
+					char		sav;
+
+					if (num_tests >= MAX_PARALLEL_TESTS)
+					{
+						fprintf(stderr, _("too many parallel tests (more than %d) in schedule file \"%s\" line %d: %s\n"),
+								MAX_PARALLEL_TESTS, schedule, line_num, scbuf);
+						exit(2);
+					}
+					sav = *c;
+					*c = '\0';
+					tests[num_tests] = pg_strdup(test);
+					num_tests++;
+					*c = sav;
+					inword = false;
+				}
+				if (*c == '\0')
+					break;		/* loop exit is here */
 			}
 			else if (!inword)
 			{
-				if (num_tests >= MAX_PARALLEL_TESTS)
-				{
-					/* can't print scbuf here, it's already been trashed */
-					fprintf(stderr, _("too many parallel tests (more than %d) in schedule file \"%s\" line %d\n"),
-							MAX_PARALLEL_TESTS, schedule, line_num);
-					exit(2);
-				}
-				tests[num_tests] = c;
-				num_tests++;
+				/* Start of a test name */
+				test = c;
 				inword = true;
 			}
 		}
@@ -1695,9 +1697,8 @@ run_schedule(const char *schedule, test_function tfunc)
 		}
 		else if (max_concurrent_tests > 0 && max_concurrent_tests < num_tests)
 		{
-			/* can't print scbuf here, it's already been trashed */
-			fprintf(stderr, _("too many parallel tests (more than %d) in schedule file \"%s\" line %d\n"),
-					max_concurrent_tests, schedule, line_num);
+			fprintf(stderr, _("too many parallel tests (more than %d) in schedule file \"%s\" line %d: %s\n"),
+					max_concurrent_tests, schedule, line_num, scbuf);
 			exit(2);
 		}
 		else if (max_connections > 0 && max_connections < num_tests)
@@ -1802,6 +1803,15 @@ run_schedule(const char *schedule, test_function tfunc)
 
 			status_end();
 		}
+
+		for (i = 0; i < num_tests; i++)
+		{
+			pg_free(tests[i]);
+			tests[i] = NULL;
+			free_stringlist(&resultfiles[i]);
+			free_stringlist(&expectfiles[i]);
+			free_stringlist(&tags[i]);
+		}
 	}
 
 	free_stringlist(&ignorelist);