🐛 FIX: Handle generator rule names across parser chains

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+* 🐛 Fix generator rule names being exhausted before all rule chains and unknown-name validation in `MarkdownIt.enable()` and `disable()`.
+
 * ✨ Add `--enable-tables` to the CLI for file, standard input and interactive parsing in [#422](https://github.com/executablebooks/markdown-it-py/pull/422)
 * 🐛 Fix CLI interactive mode joining input lines with an extra newline, which split every line into its own paragraph and broke hard line breaks, in [#172](https://github.com/executablebooks/markdown-it-py/issues/172)
 * 🐛 Fix trimming and splitting with the Python whitespace set instead of the CommonMark one, which dropped U+001C–U+001F and U+0085 from paragraphs, headings, table cells and fence info strings and let distinct reference labels resolve each other, in [#418](https://github.com/executablebooks/markdown-it-py/pull/418), thanks to [@Nexory](https://github.com/Nexory)

markdown_it/main.py

@@ -162,7 +162,7 @@ def enable(
     ) -> MarkdownIt:
         """Enable list or rules. (chainable)
 
-        :param names: rule name or list of rule names to enable.
+        :param names: rule name or iterable of rule names to enable.
         :param ignoreInvalid: set `true` to ignore errors when rule not found.
 
         It will automatically find appropriate components,
@@ -176,8 +176,7 @@ def enable(
         """
         result = []
 
-        if isinstance(names, str):
-            names = [names]
+        names = [names] if isinstance(names, str) else list(names)
 
         for chain in ["core", "block", "inline"]:
             result.extend(self[chain].ruler.enable(names, True))
@@ -200,8 +199,7 @@ def disable(
         """
         result = []
 
-        if isinstance(names, str):
-            names = [names]
+        names = [names] if isinstance(names, str) else list(names)
 
         for chain in ["core", "block", "inline"]:
             result.extend(self[chain].ruler.disable(names, True))

tests/test_api/test_main.py

@@ -544,3 +544,56 @@ def peek_rule(state, silent):
     # the rule saw the text accumulate one character at a time
     assert seen[:4] == [0, 1, 2, 3]
     assert max(seen) == 9_999
+
+
+def _check_rule_names_generator_applies_to_all_chains(method: str) -> None:
+    """An iterator must be reused across each rule chain."""
+    md = MarkdownIt("zero" if method == "enable" else "commonmark")
+    core_rule = "smartquotes" if method == "enable" else "normalize"
+    names = (name for name in [core_rule, "heading", "emphasis"])
+    assert getattr(md, method)(names) is md
+    active = md.get_active_rules()
+    for chain, name in [
+        ("core", core_rule),
+        ("block", "heading"),
+        ("inline", "emphasis"),
+        ("inline2", "emphasis"),
+    ]:
+        assert (name in active[chain]) is (method == "enable")
+
+
+def _check_rule_names_generator_reports_unknown_rules(method: str) -> None:
+    """Unknown names are checked after all chains have inspected an iterator."""
+    with pytest.raises(ValueError, match="unknown rule"):
+        getattr(MarkdownIt(), method)(name for name in ["missing-rule"])
+
+
+def _check_rule_names_generator_ignores_unknown_rules(method: str) -> None:
+    """Ignoring an unknown name must still apply the known iterator names."""
+    md = MarkdownIt("zero" if method == "enable" else "commonmark")
+    getattr(md, method)((name for name in ["missing-rule", "heading"]), True)
+    assert ("heading" in md.get_active_rules()["block"]) is (method == "enable")
+
+
+def test_enable_generator_applies_to_all_chains() -> None:
+    _check_rule_names_generator_applies_to_all_chains("enable")
+
+
+def test_disable_generator_applies_to_all_chains() -> None:
+    _check_rule_names_generator_applies_to_all_chains("disable")
+
+
+def test_enable_generator_reports_unknown_rules() -> None:
+    _check_rule_names_generator_reports_unknown_rules("enable")
+
+
+def test_disable_generator_reports_unknown_rules() -> None:
+    _check_rule_names_generator_reports_unknown_rules("disable")
+
+
+def test_enable_generator_ignores_unknown_rules() -> None:
+    _check_rule_names_generator_ignores_unknown_rules("enable")
+
+
+def test_disable_generator_ignores_unknown_rules() -> None:
+    _check_rule_names_generator_ignores_unknown_rules("disable")