py/modsys: Implement sys.intern.

Signed-off-by: stijn <[email protected]>
stinos · Dec 4, 2023 · 4c9055b · 4c9055b
1 parent f3889db
commit 4c9055b
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Showing 3 changed files with 15 additions and 0 deletions.
diff --git a/py/modsys.c b/py/modsys.c
@@ -293,6 +293,10 @@ STATIC const mp_rom_map_elem_t mp_module_sys_globals_table[] = {
     #endif
     #endif
 
+    #if MICROPY_PY_SYS_INTERN
+    { MP_ROM_QSTR(MP_QSTR_intern), MP_ROM_PTR(&mp_identity_obj) },
+    #endif
+
     #if MICROPY_PY_SYS_EXIT
     { MP_ROM_QSTR(MP_QSTR_exit), MP_ROM_PTR(&mp_sys_exit_obj) },
     #endif

diff --git a/py/mpconfig.h b/py/mpconfig.h
@@ -1434,6 +1434,12 @@ typedef double mp_float_t;
 #define MICROPY_PY_SYS_EXECUTABLE (0)
 #endif
 
+// Whether to provide "sys.identity", implemented simply as returning the argument passed
+// since strings are already interned as qstr.
+#ifndef MICROPY_PY_SYS_INTERN
+#define MICROPY_PY_SYS_INTERN (MICROPY_CONFIG_ROM_LEVEL_AT_LEAST_EVERYTHING)
+#endif
+
 // Whether to provide "sys.exit" function
 #ifndef MICROPY_PY_SYS_EXIT
 #define MICROPY_PY_SYS_EXIT (1)

diff --git a/tests/basics/sys1.py b/tests/basics/sys1.py
@@ -23,3 +23,8 @@
 else:
     # Effectively skip subtests
     print(int)
+
+try:
+    print(sys.intern('micropython') == 'micropython')
+except AttributeError:
+    print(True)