py/modsys: Add optional mutable attributes sys.ps1/ps2 and use them.

This allows customising the REPL prompt strings.

Signed-off-by: Damien George <damien@micropython.org>

1 files changed, 10 insertions, 0 deletions

diff --git a/py/repl.c b/py/repl.c
index 822e385ab..4e47cf784 100644
--- a/py/repl.c
+++ b/py/repl.c
@@ -33,6 +33,16 @@
 
 #if MICROPY_HELPER_REPL
 
+#if MICROPY_PY_SYS_PS1_PS2
+const char *mp_repl_get_psx(unsigned int entry) {
+    if (mp_obj_is_str(MP_STATE_VM(sys_mutable)[entry])) {
+        return mp_obj_str_get_str(MP_STATE_VM(sys_mutable)[entry]);
+    } else {
+        return "";
+    }
+}
+#endif
+
 STATIC bool str_startswith_word(const char *str, const char *head) {
     size_t i;
     for (i = 0; str[i] && head[i]; i++) {