cli: colitur easter <year> prints Easter and its anchors

Argv-parsed subcommand; validates the 1583..9999 domain (exit 2 otherwise);
prints 'name YYYY-MM-DD' lines. Cram test covers the output and the exit codes.

2 files changed, 24 insertions, 0 deletions

diff --git a/test/cli.t b/test/cli.t
new file mode 100644
index 0000000..319fc8c
--- /dev/null
+++ b/test/cli.t
@@ -0,0 +1,21 @@
+Easter and its Easter-relative movable feasts for a year:
+
+  $ colitur easter 2026
+  easter 2026-04-05
+  ash-wednesday 2026-02-18
+  palm-sunday 2026-03-29
+  ascension 2026-05-14
+  pentecost 2026-05-24
+  corpus-christi 2026-06-04
+
+A year outside the supported domain is rejected (exit 2):
+
+  $ colitur easter 1000
+  colitur: year 1000 out of range 1583..9999
+  [2]
+
+No/garbage arguments give a usage error (exit 2):
+
+  $ colitur
+  colitur: usage: colitur easter <year>
+  [2]
diff --git a/test/dune b/test/dune
index 3d8df19..8ee8b87 100644
--- a/test/dune
+++ b/test/dune
@@ -1,3 +1,6 @@
 (test
  (name test_colitur)
  (libraries colitur_kernel alcotest qcheck qcheck-alcotest))
+
+(cram
+ (deps %{bin:colitur}))