In _dump(), use Python PPM save, instead of C

Tests/test_image.py

@@ -270,8 +270,11 @@ def test_dump(self, tmp_path: Path) -> None:
         im = Image.new("RGB", (10, 10))
         im._dump(str(tmp_path / "temp_RGB.ppm"))
 
+        im = Image.new("RGBA", (10, 10))
+        im._dump(str(tmp_path / "temp_RGBA.ppm"))
+
         im = Image.new("HSV", (10, 10))
-        with pytest.raises(ValueError):
+        with pytest.raises(OSError):
             im._dump(str(tmp_path / "temp_HSV.ppm"))
 
     def test_comparison_with_other_type(self) -> None:

src/PIL/Image.py

@@ -731,24 +731,17 @@ def _ensure_mutable(self) -> None:
     def _dump(
         self, file: str | None = None, format: str | None = None, **options: Any
     ) -> str:
-        suffix = ""
-        if format:
-            suffix = f".{format}"
+        suffix = f".{format}" if format else ""
 
-        if not file:
-            f, filename = tempfile.mkstemp(suffix)
-            os.close(f)
-        else:
+        if file:
             filename = file
             if not filename.endswith(suffix):
-                filename = filename + suffix
-
-        self.load()
-
-        if not format or format == "PPM":
-            self.im.save_ppm(filename)
+                filename += suffix
         else:
-            self.save(filename, format, **options)
+            f, filename = tempfile.mkstemp(suffix)
+            os.close(f)
+
+        self.save(filename, format or "PPM", **options)
 
         return filename
 

src/_imaging.c

@@ -108,7 +108,7 @@
 #define S16(v) ((v) < 32768 ? (v) : ((v) - 65536))
 
 /* -------------------------------------------------------------------- */
-/* OBJECT ADMINISTRATION                        */
+/* OBJECT ADMINISTRATION                                                */
 /* -------------------------------------------------------------------- */
 
 typedef struct {
@@ -379,7 +379,7 @@ ImagingError_ValueError(const char *message) {
 }
 
 /* -------------------------------------------------------------------- */
-/* HELPERS                                */
+/* HELPERS                                                              */
 /* -------------------------------------------------------------------- */
 
 static int
@@ -683,7 +683,7 @@ getink(PyObject *color, Imaging im, char *ink) {
 }
 
 /* -------------------------------------------------------------------- */
-/* FACTORIES                                */
+/* FACTORIES                                                            */
 /* -------------------------------------------------------------------- */
 
 static PyObject *
@@ -3611,7 +3611,7 @@ _effect_spread(ImagingObject *self, PyObject *args) {
 }
 
 /* -------------------------------------------------------------------- */
-/* UTILITIES                                */
+/* UTILITIES                                                            */
 /* -------------------------------------------------------------------- */
 
 static PyObject *
@@ -3646,25 +3646,6 @@ _getcodecstatus(PyObject *self, PyObject *args) {
     return PyUnicode_FromString(msg);
 }
 
-/* -------------------------------------------------------------------- */
-/* DEBUGGING HELPERS                            */
-/* -------------------------------------------------------------------- */
-
-static PyObject *
-_save_ppm(ImagingObject *self, PyObject *args) {
-    char *filename;
-
-    if (!PyArg_ParseTuple(args, "s", &filename)) {
-        return NULL;
-    }
-
-    if (!ImagingSavePPM(self->image, filename)) {
-        return NULL;
-    }
-
-    Py_RETURN_NONE;
-}
-
 /* -------------------------------------------------------------------- */
 
 /* methods */
@@ -3748,9 +3729,6 @@ static struct PyMethodDef methods[] = {
     /* Special effects */
     {"effect_spread", (PyCFunction)_effect_spread, METH_VARARGS},
 
-    /* Misc. */
-    {"save_ppm", (PyCFunction)_save_ppm, METH_VARARGS},
-
     /* arrow */
     {"__arrow_c_schema__", (PyCFunction)ExportArrowSchemaPyCapsule, METH_VARARGS},
     {"__arrow_c_array__", (PyCFunction)ExportArrowArrayPyCapsule, METH_VARARGS},

src/libImaging/File.c

@@ -41,37 +41,3 @@ ImagingSaveRaw(Imaging im, FILE *fp) {
 
     return 1;
 }
-
-int
-ImagingSavePPM(Imaging im, const char *outfile) {
-    FILE *fp;
-
-    if (!im) {
-        (void)ImagingError_ValueError(NULL);
-        return 0;
-    }
-
-    fp = fopen(outfile, "wb");
-    if (!fp) {
-        PyErr_SetString(PyExc_OSError, "error when accessing file");
-        return 0;
-    }
-
-    if (im->mode == IMAGING_MODE_1 || im->mode == IMAGING_MODE_L) {
-        /* Write "PGM" */
-        fprintf(fp, "P5\n%d %d\n255\n", im->xsize, im->ysize);
-    } else if (im->mode == IMAGING_MODE_RGB) {
-        /* Write "PPM" */
-        fprintf(fp, "P6\n%d %d\n255\n", im->xsize, im->ysize);
-    } else {
-        fclose(fp);
-        (void)ImagingError_ModeError();
-        return 0;
-    }
-
-    ImagingSaveRaw(im, fp);
-
-    fclose(fp);
-
-    return 1;
-}