From e649cb811e757f4f8385e66da5d88123a25679fe Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Mon, 5 Oct 2020 19:59:13 +0100
Subject: [PATCH] do JS bigfloat repr tests

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 .gitignore       |  1 +
 Makefile         |  6 +++++-
 extract-bf-tests | 13 +++++++++++++
 src/bigfloat.rs  |  1 +
 4 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100755 extract-bf-tests

diff --git a/.gitignore b/.gitignore
index 41bbff84..3cd8f27b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
 templates/script.js
 templates/bigfloat-tests.js
+templates/bigfloat-tests-auto.ts
 templates/LICENCE
 templates/AGPLv3
 templates/CC-BY-SA-3.0
diff --git a/Makefile b/Makefile
index 2e445ad7..e1ef891c 100644
--- a/Makefile
+++ b/Makefile
@@ -90,7 +90,11 @@ templates/%.js: tsc-wrap tsconfig.json
 	./tsc-wrap $@ tsconfig.json $(filter %.ts,$^)
 
 templates/script.js: $(TS_SRC_FILES)
-templates/bigfloat-tests.js: templates/bigfloat.ts templates/bigfloat-tests.ts
+templates/bigfloat-tests.js: templates/bigfloat.ts \
+	templates/bigfloat-tests.ts templates/bigfloat-tests-auto.ts
+
+templates/bigfloat-tests-auto.ts: extract-bf-tests src/bigfloat.rs
+	./$^ >$@.tmp && mv -f $@.tmp $@
 
 js-check: templates/bigfloat-tests.js
 	nodejs <$<
diff --git a/extract-bf-tests b/extract-bf-tests
new file mode 100755
index 00000000..b23f8693
--- /dev/null
+++ b/extract-bf-tests
@@ -0,0 +1,13 @@
+#!/usr/bin/perl -w
+use strict;
+
+sub chk_repr ($) {
+  my ($p) = @_;
+  print "assert_eq($p, Bigfloats.pack(Bigfloats.unpack($p as any)));\n";
+}
+
+while (<>) {
+  next unless m/^mod test/..0;
+  my $l = $_;
+  $l =~ s{bf\((\"[^"]+\")\)}{ chk_repr($1) }ge;
+}
diff --git a/src/bigfloat.rs b/src/bigfloat.rs
index 51d7a6d3..69c75451 100644
--- a/src/bigfloat.rs
+++ b/src/bigfloat.rs
@@ -385,6 +385,7 @@ impl Serialize for Bigfloat {
 
 #[cfg(test)]
 mod test {
+  // everything from here on is seded by the js test extractor!
   use super::*;
 
   fn bf(s: &str) -> Bigfloat {
-- 
2.30.2