fn arbitrary_metadata()

in safetensors/src/tensor.rs [919:966]

• 43 lines of code
• 3 McCabe index (conditional complexity)

    fn arbitrary_metadata() -> impl Strategy<Value = Metadata> {
        // We generate at least one tensor.
        (1..MAX_TENSORS)
            .prop_flat_map(|size| {
                // Returns a strategy generating `size` data types and shapes.
                (
                    prop::collection::vec(arbitrary_dtype(), size),
                    prop::collection::vec(arbitrary_shape(), size),
                )
            })
            .prop_filter_map("Misaligned slices", |(dtypes, shapes)| {
                // Returns a valid metadata object for a random (length, dtypes, shapes) triple.
                let mut start = 0;
                let tensors: Vec<TensorInfo> = dtypes
                    .iter()
                    .zip(shapes)
                    .flat_map(|(dtype, shape)| {
                        // This cannot overflow because the size of
                        // the vector and elements are so small.
                        let bitlength: usize = shape.iter().product::<usize>() * dtype.bitsize();
                        if bitlength % 8 != 0 {
                            return None;
                        }
                        let length = bitlength.div_ceil(8);
                        let end = start + length;
                        let tensor = TensorInfo {
                            dtype: *dtype,
                            shape,
                            data_offsets: (start, end),
                        };
                        start = end;
                        Some(tensor)
                    })
                    .collect();
                let index_map = (0..tensors.len())
                    .map(|index| (format!("t.{index}"), index))
                    .collect();
                if tensors.is_empty() {
                    None
                } else {
                    Some(Metadata {
                        metadata: None,
                        tensors,
                        index_map,
                    })
                }
            })
    }