add a test for tuncated image files

test/test-suite/helpers/helpers.py

@@ -9,6 +9,7 @@ import pyvips
 
 IMAGES = os.path.join(os.path.dirname(__file__), os.pardir, 'images')
 JPEG_FILE = os.path.join(IMAGES, "sample.jpg")
+TRUNCATED_FILE = os.path.join(IMAGES, "truncated.jpg")
 SRGB_FILE = os.path.join(IMAGES, "sRGB.icm")
 MATLAB_FILE = os.path.join(IMAGES, "sample.mat")
 PNG_FILE = os.path.join(IMAGES, "sample.png")

test/test-suite/test_foreign.py

@@ -11,7 +11,7 @@ from helpers import \
     JPEG_FILE, SRGB_FILE, MATLAB_FILE, PNG_FILE, TIF_FILE, OME_FILE, \
     ANALYZE_FILE, GIF_FILE, WEBP_FILE, EXR_FILE, FITS_FILE, OPENSLIDE_FILE, \
     PDF_FILE, SVG_FILE, SVGZ_FILE, SVG_GZ_FILE, GIF_ANIM_FILE, DICOM_FILE, \
-    BMP_FILE, NIFTI_FILE, ICO_FILE, HEIC_FILE, \
+    BMP_FILE, NIFTI_FILE, ICO_FILE, HEIC_FILE, TRUNCATED_FILE, \
     temp_filename, assert_almost_equal_objects, have, skip_if_no
 
 
@@ -234,6 +234,19 @@ class TestForeign:
             # format area at the end
             assert y.startswith("hello world")
 
+    @skip_if_no("jpegload")
+    def test_truncated(self):
+        # This should open (there's enough there for the header)
+        im = pyvips.Image.new_from_file(TRUNCATED_FILE)
+        # but this should fail with a warning, and knock TRUNCATED_FILE out of
+        # the cache
+        x = im.avg()
+
+        # now we should open again, but it won't come from cache, it'll reload
+        im = pyvips.Image.new_from_file(TRUNCATED_FILE)
+        # and this should fail with a warning once more
+        x = im.avg()
+
     @skip_if_no("pngload")
     def test_png(self):
         def png_valid(im):