tests: idempotnent ipynb (marimo-team#7939)

Co-authored-by: dmadisetti <dmadisetti@coreweave.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: 3 people

marimo/_convert/common/format.py

@@ -9,8 +9,12 @@
 if TYPE_CHECKING:
     from marimo._ast.cell import Cell, CellImpl
 
+DEFAULT_MARKDOWN_PREFIX = "r"
 
-def markdown_to_marimo(source: str) -> str:
+
+def markdown_to_marimo(
+    source: str, prefix: str = DEFAULT_MARKDOWN_PREFIX
+) -> str:
     # NB. This should be kept in sync with the logic in
     # frontend/src/core/codemirror/language/languages/markdown.ts
     # ::transformOut
@@ -19,7 +23,7 @@ def markdown_to_marimo(source: str) -> str:
     # 6 quotes in a row breaks
     if not source:
         source = " "
-    return codegen.construct_markdown_call(source, '"""', "r")
+    return codegen.construct_markdown_call(source, '"""', prefix)
 
 
 def sql_to_marimo(

marimo/_convert/ipynb/from_ir.py

@@ -32,6 +32,17 @@
 
 # Note: We intentionally omit "version" as it would vary across environments
 # and break reproducibility. The marimo_version in metadata is sufficient.
+_MD_PREFIX_RE = re.compile(r'mo\.md\(([fFrR]*)(?:"""|\'\'\'|"|\')')
+
+
+def _extract_markdown_prefix(code: str) -> str:
+    """Extract the string prefix from a mo.md() call (e.g. '', 'r', 'f', 'fr')."""
+    m = _MD_PREFIX_RE.search(code)
+    if m:
+        return m.group(1).lower()
+    return ""
+
+
 DEFAULT_LANGUAGE_INFO = {
     "codemirror_mode": {"name": "ipython", "version": 3},
     "file_extension": ".py",
@@ -162,7 +173,9 @@ def _create_ipynb_cell(
                 nbformat.NotebookNode,
                 nbformat.v4.new_markdown_cell(markdown_string, id=cell_id),  # type: ignore[no-untyped-call]
             )
-            _add_marimo_metadata(node, name, config)
+            _add_marimo_metadata(
+                node, name, config, md_prefix=_extract_markdown_prefix(code)
+            )
             return node
 
     node = cast(
@@ -176,14 +189,21 @@ def _create_ipynb_cell(
 
 
 def _add_marimo_metadata(
-    node: NotebookNode, name: str, config: CellConfig
+    node: NotebookNode,
+    name: str,
+    config: CellConfig,
+    md_prefix: Optional[str] = None,
 ) -> None:
     """Add marimo-specific metadata to a notebook cell."""
     marimo_metadata: dict[str, Any] = {}
     if config.is_different_from_default():
         marimo_metadata["config"] = config.asdict_without_defaults()
     if not is_internal_cell_name(name):
         marimo_metadata["name"] = name
+    if md_prefix is not None:
+        # Always store prefix for markdown cells so importer knows the original
+        # prefix and can distinguish marimo-created cells from foreign ipynb cells
+        marimo_metadata["md_prefix"] = md_prefix
     if marimo_metadata:
         node["metadata"]["marimo"] = marimo_metadata
 

marimo/_convert/ipynb/to_ir.py

@@ -11,10 +11,14 @@
 
 from marimo._ast.cell import CellConfig
 from marimo._ast.compiler import compile_cell
+from marimo._ast.names import DEFAULT_CELL_NAME
 from marimo._ast.transformers import NameTransformer, RemoveImportTransformer
 from marimo._ast.variables import is_local
 from marimo._ast.visitor import Block, NamedNode, ScopedVisitor
-from marimo._convert.common.format import markdown_to_marimo
+from marimo._convert.common.format import (
+    DEFAULT_MARKDOWN_PREFIX,
+    markdown_to_marimo,
+)
 from marimo._runtime.dataflow import DirectedGraph
 from marimo._schemas.serialization import (
     AppInstantiation,
@@ -31,6 +35,7 @@
 @dataclass
 class CodeCell:
     source: str
+    name: str = field(default_factory=lambda: DEFAULT_CELL_NAME)
     config: CellConfig = field(default_factory=CellConfig)
 
 
@@ -1169,24 +1174,30 @@ def bind_cell_metadata(
     cells: list[CodeCell] = []
     for source, meta, hide_code in zip(sources, metadata, hide_flags):
         tags: set[str] = set(meta.get("tags", []))
-        if "hide-cell" in tags:
-            tags.discard("hide-cell")
-            hide_code = True
-        if tags:
-            source = f"# Cell tags: {', '.join(sorted(tags))}\n{source}"
 
         # Extract marimo-specific cell config if present
         marimo_meta = meta.get("marimo", {})
         marimo_config = marimo_meta.get("config", {})
+        name = marimo_meta.get("name", DEFAULT_CELL_NAME)
 
-        # Merge marimo config with existing flags
-        # marimo config takes precedence for hide_code if present
+        # Determine hide_code with priority: marimo config > tags > hide_flags default
         if "hide_code" in marimo_config:
             hide_code = marimo_config["hide_code"]
+        elif "hide-cell" in tags:
+            tags.discard("hide-cell")
+            hide_code = True
+        elif "marimo" in meta:
+            # Cell was created by marimo; marimo would have stored hide_code=True
+            # explicitly if needed, so default to False instead of is_markdown
+            hide_code = False
+
+        if tags:
+            source = f"# Cell tags: {', '.join(sorted(tags))}\n{source}"
 
         cells.append(
             CodeCell(
                 source=source,
+                name=name,
                 config=CellConfig(
                     hide_code=hide_code,
                     column=marimo_config.get("column"),
@@ -1393,7 +1404,11 @@ def convert_from_ipynb_to_notebook_ir(
         )
         is_markdown: bool = cell["cell_type"] == "markdown"
         if is_markdown:
-            source = markdown_to_marimo(source)
+            cell_meta = cell.get("metadata", {})
+            md_prefix = cell_meta.get("marimo", {}).get(
+                "md_prefix", DEFAULT_MARKDOWN_PREFIX
+            )
+            source = markdown_to_marimo(source, prefix=md_prefix)
         elif inline_meta is None:
             # Eagerly find PEP 723 metadata, first match wins
             inline_meta, source = extract_inline_meta(source)
@@ -1420,6 +1435,7 @@ def convert_from_ipynb_to_notebook_ir(
         cells=[
             CellDef(
                 code=cell.source,
+                name=cell.name,
                 options=cell.config.asdict(),
             )
             for cell in transformed_cells

tests/_cli/snapshots/export/ipynb/ipynb.txt

@@ -35,7 +35,11 @@
   {
    "cell_type": "markdown",
    "id": "vblA",
-   "metadata": {},
+   "metadata": {
+    "marimo": {
+     "md_prefix": ""
+    }
+   },
    "source": [
     "plain markdown"
    ]

tests/_cli/snapshots/export/ipynb/ipynb_topdown.txt

@@ -25,7 +25,11 @@
   {
    "cell_type": "markdown",
    "id": "vblA",
-   "metadata": {},
+   "metadata": {
+    "marimo": {
+     "md_prefix": ""
+    }
+   },
    "source": [
     "plain markdown"
    ]

tests/_cli/snapshots/export/ipynb/ipynb_with_media_outputs.txt

@@ -27,6 +27,7 @@
    "id": "MJUe",
    "metadata": {
     "marimo": {
+     "md_prefix": "",
      "name": "pure_markdown_cell"
     }
    },

tests/_cli/snapshots/export/ipynb/ipynb_with_outputs.txt

@@ -55,7 +55,11 @@
   {
    "cell_type": "markdown",
    "id": "vblA",
-   "metadata": {},
+   "metadata": {
+    "marimo": {
+     "md_prefix": ""
+    }
+   },
    "source": [
     "plain markdown"
    ]

tests/_convert/ipynb/fixtures/py/cell_config.py

@@ -0,0 +1,41 @@
+import marimo
+
+__generated_with = "0.0.0"
+app = marimo.App()
+
+
+@app.cell
+def _():
+    import marimo as mo
+
+    return (mo,)
+
+
+@app.cell
+def _():
+    x = 1
+    return (x,)
+
+
+@app.cell(hide_code=True)
+def _(mo):
+    mo.md("""
+    # This cell is hidden
+    """)
+    return
+
+
+@app.cell(disabled=True)
+def _(x):
+    y = x + 1
+    return (y,)
+
+
+@app.cell
+def _(y):
+    print(y)
+    return
+
+
+if __name__ == "__main__":
+    app.run()

tests/_convert/ipynb/fixtures/py/cell_names_and_defs.py

@@ -0,0 +1,52 @@
+import marimo
+
+__generated_with = "0.0.0"
+app = marimo.App()
+
+
+@app.cell
+def my_imports():
+    import os
+    import sys
+
+    return os, sys
+
+
+@app.cell
+def compute(os, sys):
+    result = os.getcwd() + sys.platform
+    return (result,)
+
+
+@app.cell
+def display(result):
+    print(result)
+    return
+
+
+@app.function
+def add(a, b):
+    return a + b
+
+
+@app.function(hide_code=True)
+def subtract(a, b):
+    return a - b
+
+
+@app.class_definition
+class MyClass:
+    def __init__(self, val):
+        self.val = val
+    def double(self):
+        return self.val * 2
+
+
+@app.class_definition(hide_code=True)
+class HiddenClass:
+    def __init__(self, val):
+        self.val = val
+
+
+if __name__ == "__main__":
+    app.run()

tests/_convert/ipynb/fixtures/py/complex_file_format.py

@@ -10,7 +10,7 @@
 
 import marimo
 
-__generated_with = "0.19.2"
+__generated_with = "0.0.0"
 app = marimo.App(width="medium", auto_download=["html"], sql_output="native")
 
 with app.setup:
@@ -36,6 +36,7 @@ def imports():
     """Named cell with imports."""
     import pandas as pd
     import numpy as np
+
     return np, pd