Add option for gslides markdown parser to raise on unsupported elements

[ZmeiGorynych]

Summary by CodeRabbit

• New Features

  • Added a public UnsupportedMarkdownError export for signaling unsupported Markdown.
  • Added a strict (default: true) option across Markdown parsing and text-writing APIs — strict mode raises on unsupported constructs; lenient mode logs and skips them.
  • Propagated strict behavior to text elements, shapes, and table cell text writing.

• Tests

  • Added tests covering unsupported Markdown handling in strict and lenient modes, and top-level import of the new error.

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[coderabbitai]

📝 Walkthrough

Walkthrough

Adds an UnsupportedMarkdownError exception and a strict: bool = True flag across the markdown-to-IR pipeline and text-writing APIs; when strict is True unsupported Markdown raises the exception, otherwise elements are logged and skipped.

Changes

Cohort / File(s)	Summary
Core markdown parser gslides_api/agnostic/markdown_parser.py	Adds UnsupportedMarkdownError; adds strict: bool = True to parse_markdown_to_ir and all internal helpers; unsupported-element handling now raises in strict mode or logs-and-skips when non-strict.
Top-level export gslides_api/__init__.py	Re-exports UnsupportedMarkdownError from gslides_api.agnostic.markdown_parser.
Element text writers gslides_api/element/shape.py, gslides_api/element/text_content.py, gslides_api/element/table.py	Thread strict: bool = True through public write APIs (ShapeElement.write_text, TextContent.write_text_requests, TableElement.write_text_to_cell_requests / write_text_to_cell) to propagate markdown strictness.
Markdown helper gslides_api/markdown/from_markdown.py	Adds strict: bool = True to markdown_to_text_elements() and forwards it to parse_markdown_to_ir().
Tests tests/test_markdown_features.py	Adds TestUnsupportedMarkdownElements verifying strict vs non-strict behavior for fenced code blocks, quotes, code blocks, images, auto-links; verifies top-level import of UnsupportedMarkdownError.

Sequence Diagram(s)

(omitted)

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• Egor/dev 974 gslides factor out runs to markdown logic to share with pptx and gslides #48: Modifies the same parse_markdown_to_ir pipeline in gslides_api/agnostic/markdown_parser.py.
• Egor/dev 942 gslides factor out abstractions to help powerpoint support #47: Refactors/adjusts internals of markdown_parser.py and touches similar helper functions updated here.
• Egor/dev 977 clean up agnostic classes for deck from nothing flow #50: Changes table text-writing logic (write_text_to_cell_requests / write_text_to_cell), related to the propagated strict parameter.

Poem

🐰 In a burrow of lines and tags I play,

I sniff for markdown that goes astray.
If strict I stand, I thump and declare,
If gentle, I skip with soft rabbit care.
Hopping through changes — hooray! 🥕

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately and concisely describes the main change: adding a strict mode option to the markdown parser to raise errors on unsupported elements.
Docstring Coverage	✅ Passed	Docstring coverage is 90.91% which is sufficient. The required threshold is 80.00%.

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✨ Finishing touches

• 📝 Generate docstrings

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[coderabbitai]

Actionable comments posted: 1

🤖 Fix all issues with AI agents

In `@tests/test_markdown_features.py`:
- Around line 278-282: In test_exception_is_exported remove the stray orphaned
comment line ("# Some malformed markdown might legitimately fail") inside the
test function; edit the test_exception_is_exported method so it only contains
the docstring, the import aliasing of UnsupportedMarkdownError and the assertion
(i.e. reference the test_exception_is_exported function and
UnsupportedMarkdownError to locate and delete that leftover comment).

🧹 Nitpick comments (3)

gslides_api/agnostic/markdown_parser.py (2)

14-17: Consider removing redundant pass statement.

The pass statement is unnecessary when a class body already contains a docstring.

♻️ Suggested simplification

 class UnsupportedMarkdownError(ValueError):
     """Raised when markdown contains elements that cannot be converted to the target format."""
-
-    pass

---

142-149: Consider centralizing error message construction.

The error message pattern is repeated in three locations (lines 143-146, 269-272, 344-347). This could be simplified by adding a factory method to UnsupportedMarkdownError, which would also address the Ruff TRY003 hint about long messages outside exception classes.

♻️ Suggested refactor

Update the exception class:

class UnsupportedMarkdownError(ValueError):
    """Raised when markdown contains elements that cannot be converted to the target format."""

    `@classmethod`
    def for_element(cls, element_type: str, node_name: str) -> "UnsupportedMarkdownError":
        return cls(
            f"Unsupported {element_type} element: {node_name}. "
            f"Use strict=False to skip unsupported elements."
        )

Then replace the inline raises:

-            raise UnsupportedMarkdownError(
-                f"Unsupported block element: {type(node).__name__}. "
-                f"Use strict=False to skip unsupported elements."
-            )
+            raise UnsupportedMarkdownError.for_element("block", type(node).__name__)

gslides_api/element/table.py (1)

152-215: Expose strict on higher-level table update helpers.

Now that strict is plumbed into the cell write path, consider threading a strict parameter through content_update_requests(...) and create_element_from_markdown_requests(...) so table creation from markdown can opt into lenient behavior too.

[coderabbitai]

⚠️ Potential issue | 🟡 Minor

Remove orphaned comment.

Line 282 contains an orphaned comment that appears to be a leftover from a previous test case.

🧹 Suggested fix

     def test_exception_is_exported(self):
         """Test that UnsupportedMarkdownError can be imported from the package."""
         from gslides_api import UnsupportedMarkdownError as ImportedError
         assert ImportedError is UnsupportedMarkdownError
-                # Some malformed markdown might legitimately fail

📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change

	def test_exception_is_exported(self):
	"""Test that UnsupportedMarkdownError can be imported from the package."""
	from gslides_api import UnsupportedMarkdownError as ImportedError
	assert ImportedError is UnsupportedMarkdownError
	# Some malformed markdown might legitimately fail
	def test_exception_is_exported(self):
	"""Test that UnsupportedMarkdownError can be imported from the package."""
	from gslides_api import UnsupportedMarkdownError as ImportedError
	assert ImportedError is UnsupportedMarkdownError

🤖 Prompt for AI Agents

In `@tests/test_markdown_features.py` around lines 278 - 282, In
test_exception_is_exported remove the stray orphaned comment line ("# Some
malformed markdown might legitimately fail") inside the test function; edit the
test_exception_is_exported method so it only contains the docstring, the import
aliasing of UnsupportedMarkdownError and the assertion (i.e. reference the
test_exception_is_exported function and UnsupportedMarkdownError to locate and
delete that leftover comment).