share: Show the master fingerprint after the threshold

src/codex32/cli.py

@@ -189,6 +189,10 @@ def _share_command(index: str, plain: bool, context: _CliContext, core: BitcoinC
         derived = derive_share(artifacts, index)
     except CodexError as error:
         raise _CommandError(str(error)) from error
+    if core is not None and sys.stdout.isatty() and not plain:
+        given = [artifact for artifact in artifacts if isinstance(artifact, Secret)]
+        seed = cast(MasterSeed, given[0] if given else _secret(artifacts))
+        _print(f"Master fingerprint: {core.fingerprint(seed).hex().upper()}\n")
     _emit(derived, plain)
     if sys.stdin.isatty() and sys.stdout.isatty() and not plain:
         try:

tests/test_cli.py

@@ -1754,13 +1754,15 @@ def test_create_rejects_bip39_partial_basis_and_selector_conflicts() -> None:
         assert result.exit_code != 0
 
 
-def test_terminal_secret_has_fingerprint_but_share_does_not() -> None:
-    secret = _invoke_terminal(["secret"], VECTOR_1["secret_s"])
+def test_terminal_secret_and_share_show_the_master_fingerprint() -> None:
+    secret = _invoke_terminal(["secret"], VECTOR_2["share_A"], VECTOR_2["share_C"])
     share = _invoke_terminal(["share", "d"], VECTOR_2["share_A"], VECTOR_2["share_C"])
+    from_secret = _invoke_terminal(["share", "d"], VECTOR_2["secret_S"], VECTOR_2["share_C"])
+    fingerprint = _FakeBitcoinCore().fingerprint(cast(MasterSeed, parse_codex32(VECTOR_2["secret_S"])))
+    line = f"Master fingerprint: {fingerprint.hex().upper()}"
 
-    assert secret.exit_code == share.exit_code == 0
-    assert "Master fingerprint:" in secret.stdout
-    assert "Master fingerprint:" not in share.stdout
+    assert secret.exit_code == share.exit_code == from_secret.exit_code == 0
+    assert line in secret.stdout and line in share.stdout and line in from_secret.stdout
     assert "Backup identifier:" in secret.stdout and "Backup identifier:" in share.stdout