From 53f8a06d49d7347a3e7f030ac1288b3fa548d92d Mon Sep 17 00:00:00 2001
From: Julian Smith <julian.smith@artifex.com>
Date: Sat, 28 Sep 2024 22:57:31 +0100
Subject: [PATCH] src/__init__.py tests/test_general.py: improve exception if
 fz_open_document_with_stream() fails.

We wrap fz_open_document_with_stream(), converting exception to FileDataError;
this makes things behave similarly to when we call fz_open_document().

Addresses #3905.
---
 src/__init__.py       |  8 ++++++--
 tests/test_general.py | 11 +++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/src/__init__.py b/src/__init__.py
index 4502f91e3..39350d1c8 100644
--- a/src/__init__.py
+++ b/src/__init__.py
@@ -2812,7 +2812,11 @@ def __init__(self, filename=None, stream=None, filetype=None, rect=None, width=0
                 #   handler = fz_recognize_document(gctx, filetype);
                 #   if (!handler) raise ValueError( MSG_BAD_FILETYPE)
                 # but prefer to leave fz_open_document_with_stream() to raise.
-                doc = mupdf.fz_open_document_with_stream(magic, data)
+                try:
+                    doc = mupdf.fz_open_document_with_stream(magic, data)
+                except Exception as e:
+                    if g_exceptions_verbose > 1:    exception_info()
+                    raise FileDataError(f'Failed to open stream') from e
             else:
                 if filename:
                     if not filetype:
@@ -13168,7 +13172,7 @@ def width(self):
                     pass
                 else:
                     #assert not inspect.isroutine(value)
-                    #log(f'importing {name}')
+                    #log(f'importing {_name=} {_value=}.')
                     setattr(_self, _name, _value)
                     #log(f'{getattr( self, name, None)=}')
     else:
diff --git a/tests/test_general.py b/tests/test_general.py
index 5d6a2f56a..0b5ce3bc9 100644
--- a/tests/test_general.py
+++ b/tests/test_general.py
@@ -1353,3 +1353,14 @@ def test_3859():
             assert type(v)==pymupdf.mupdf.PdfObj, f'`v` is not a pymupdf.mupdf.PdfObj.'
     else:
         assert not hasattr(pymupdf.mupdf, 'PDF_TRUE')
+
+def test_3905():
+    data = b'A,B,C,D\r\n1,2,1,2\r\n2,2,1,2\r\n'
+    try:
+        document = pymupdf.open(stream=data)
+    except pymupdf.FileDataError as e:
+        pass
+    else:
+        assert 0
+    wt = pymupdf.TOOLS.mupdf_warnings()
+    assert wt == 'format error: cannot recognize version marker\ntrying to repair broken xref\nrepairing PDF document'