Feature/semantic error precision

src/algolab/environment.py

@@ -6,6 +6,7 @@
 from typing import Any, Optional
 
 from .errors import RuntimeErrorAlgoLab, SemanticErrorAlgoLab
+from .utils import build_suggestion_string, suggest_var
 
 
 @dataclass(frozen=True)
@@ -88,7 +89,9 @@ def _resolve(self, name: str) -> Variable:
 			return self._values[name]
 		if self._parent is not None:
 			return self._parent._resolve(name)
-		raise SemanticErrorAlgoLab(f"Variable non declaree: {name}")
+		suggestion = suggest_var(name, self._values.keys())
+		suggestion_message = build_suggestion_string(suggestion)
+		raise SemanticErrorAlgoLab(f"Variable non declaree: {name}.{suggestion_message}")
 
 	def _coerce_value(self, type_spec: TypeSpec, value: Any) -> Any:
 		if type_spec.is_array:

src/algolab/utils.py

@@ -0,0 +1,21 @@
+""" Utility functions for AlgoLab."""
+
+from difflib import SequenceMatcher, get_close_matches
+
+
+def suggest_var(typo: str, names: list[str]) -> str:
+    if not names:
+        return ""
+
+    matches = get_close_matches(typo, names, n=1)
+    if matches:
+        return matches[0]
+
+    ranked = sorted(names, key=lambda n: SequenceMatcher(None, typo, n).ratio(), reverse=True)
+    return ranked[0]
+
+
+def build_suggestion_string(suggestion: str):
+    if not suggestion:
+        return ""
+    return f" Vouliez-vous dire '{suggestion}' ?"

tests/test_errors.py

@@ -1,7 +1,6 @@
 from __future__ import annotations
 
 import pytest
-
 from algolab.errors import SemanticErrorAlgoLab, SyntaxErrorAlgoLab
 from algolab.interpreter import Interpreter
 from algolab.parser import parse_source
@@ -36,3 +35,15 @@ def test_semantic_error_on_undeclared_variable() -> None:
     with pytest.raises(SemanticErrorAlgoLab) as exc_info:
         Interpreter().run(source)
     assert "non declaree" in str(exc_info.value)
+
+
+def test_semantic_error_on_typo_variable() -> None:
+    source = """
+    Variable x : Entier
+    Debut
+      y <- 1
+    Fin
+    """.strip()
+    with pytest.raises(SemanticErrorAlgoLab) as exc_info:
+        Interpreter().run(source)
+    assert "Vouliez-vous dire 'x' ?" in str(exc_info.value)