Merge pull request #1855 from Smit-create/i-1839

ASR: Fix a bug in dict len

Author: certik

integration_tests/test_dict_01.py

@@ -16,4 +16,12 @@ def test_dict():
     assert abs(rollnumber2cpi[0] - 1.1) <= 1e-12
     assert len(rollnumber2cpi) == 1001
 
+def test_issue_1839():
+    assert len({1: 2, 1: 3, 4: 5}) == 2
+    x: dict[i32, i32] = {}
+    x = {1: 1, 1: 2, 1: 3}
+    assert len(x) == 1
+
+
 test_dict()
+test_issue_1839()

src/lpython/semantics/python_intrinsic_eval.h

@@ -349,12 +349,10 @@ struct IntrinsicNodeHandler {
             return (ASR::asr_t *)ASR::down_cast<ASR::expr_t>(
                     ASR::make_StringLen_t(al, loc, arg, to_type, value));
         } else if (ASR::is_a<ASR::Set_t>(*type)) {
-            if (ASRUtils::expr_value(arg) != nullptr) {
-                int64_t ival = (int64_t)ASR::down_cast<ASR::SetConstant_t>(
-                                        ASRUtils::expr_value(arg))->n_elements;
-                value = ASR::down_cast<ASR::expr_t>(make_IntegerConstant_t(al,
-                                loc, ival, to_type));
-            }
+            // Skip for set as they can have multiple same values
+            // which shouldn't account for len.
+            // Example: {1, 1, 1, 3} and the length should be 2.
+            // So it should be handled in the backend.
             return (ASR::asr_t *)ASR::down_cast<ASR::expr_t>(
                     ASR::make_SetLen_t(al, loc, arg, to_type, value));
         } else if (ASR::is_a<ASR::Tuple_t>(*type)) {
@@ -371,12 +369,10 @@ struct IntrinsicNodeHandler {
             return (ASR::asr_t *)ASR::down_cast<ASR::expr_t>(
                     ASR::make_ListLen_t(al, loc, arg, to_type, value));
         } else if (ASR::is_a<ASR::Dict_t>(*type)) {
-            if (ASRUtils::expr_value(arg) != nullptr) {
-                int64_t ival = (int64_t)ASR::down_cast<ASR::DictConstant_t>(
-                                        ASRUtils::expr_value(arg))->n_keys;
-                value = ASR::down_cast<ASR::expr_t>(make_IntegerConstant_t(al,
-                                loc, ival, to_type));
-            }
+            // Skip for dictionary as they can have multiple same keys
+            // which shouldn't account for len.
+            // Example: {1: 2, 1: 3, 1: 4} and the length should be 1.
+            // So it should be handled in the backend.
             return (ASR::asr_t *)ASR::down_cast<ASR::expr_t>(
                     ASR::make_DictLen_t(al, loc, arg, to_type, value));
         }

tests/reference/asr-constants1-5828e8a.json

@@ -6,7 +6,7 @@
     "outfile": null,
     "outfile_hash": null,
     "stdout": "asr-constants1-5828e8a.stdout",
-    "stdout_hash": "db1b5652c2fca471c43f0523c3ec810113caa1fd5f2be545084cb7e5",
+    "stdout_hash": "85c3149c95930b691c248030d7907a6649078d38d3509ad54f78d891",
     "stderr": null,
     "stderr_hash": null,
     "returncode": 0

tests/reference/asr-constants1-5828e8a.stdout

@@ -1479,7 +1479,7 @@
                                                 )
                                             )
                                             (Integer 4 [])
-                                            (IntegerConstant 3 (Integer 4 []))
+                                            ()
                                         )
                                         ()
                                     )
@@ -1508,7 +1508,7 @@
                                                 )
                                             )
                                             (Integer 4 [])
-                                            (IntegerConstant 3 (Integer 4 []))
+                                            ()
                                         )
                                         ()
                                     )