Re: [PATCH v3 03/10] progress.c tests: make start/stop verbs on stdin

Change the usage of the "test-tool progress" introduced in
2bb74b53a49 (Test the progress display, 2019-09-16) to take command
like "start" and "stop" on stdin, instead of running them implicitly.

This makes for tests that are easier to read, since the recipe will
mirror the API usage, and allows for easily testing invalid usage that
would yield (or should yield) a BUG(), e.g. providing two "start"
calls in a row. A subsequent commit will add such tests.

Signed-off-by: Ævar Arnfjörð Bjarmason <redacted>
---
 t/helper/test-progress.c    | 37 ++++++++++++++++-------
 t/t0500-progress-display.sh | 58 +++++++++++++++++++++++--------------
 2 files changed, 63 insertions(+), 32 deletions(-)

diff --git a/t/helper/test-progress.c b/t/helper/test-progress.c
index 50fd3be3dad..45ccbafa9da 100644
--- a/t/helper/test-progress.c
+++ b/t/helper/test-progress.c

@@ -19,34 +23,43 @@
 #include "parse-options.h"
 #include "progress.h"
 #include "strbuf.h"
+#include "string-list.h"
 
 int cmd__progress(int argc, const char **argv)
 {
-	int total = 0;
-	const char *title;
+	const char *const default_title = "Working hard";
+	struct string_list list = STRING_LIST_INIT_DUP;
+	const struct string_list_item *item;

diff --git a/t/t0500-progress-display.sh b/t/t0500-progress-display.sh
index f37cf2eb9c9..27ab4218b01 100755
--- a/t/t0500-progress-display.sh
+++ b/t/t0500-progress-display.sh

@@ -18,6 +18,7 @@ test_expect_success 'simple progress display' '
 	EOF
 
 	cat >in <<-\EOF &&
+	start 0