React component won't re-render on state change

Question

Here is my code. The imageChunks state variable is not updating correctly. Selecting an image returns an empty array. Selecting another image returns an array of the last image's base64 chunks. It seems that setImageChunks() is not triggering a re-render. What is causing this? Any help would be appreciated.

const [ imageChunks, setImageChunks ] = useState([])
    
const handleImageChange = async (e) => {    
            const files = e.target.files
    
            // Break image base64 string into chunks for database upload, store each in object with series (filename) and part
            const getChunks = (filename, baseStr, chunkSize) => {
                const str = baseStr.split("")
                const chunks = []
                let part = 0
                let count = str.length
                let start = 0
                while (count){
                    part++
                    start = str.length - count
                    const allowedCount = count < chunkSize ? count : chunkSize
                    chunks.push({
                        series: filename,
                        part: part,
                        data: str.slice(start, start + allowedCount).join("")
                    })
                    count -= allowedCount
                }
                
                return chunks 
            }
    
            // empty imageChunks array to prepare for new file selection
            const fileChunks = []
    
            for (let i = 0; i < files.length; i++){
                // Push file name to product object imageFiles array  
                const fileNames =  formValues.imageFiles
                fileNames.push(files[i].name)
                setFormValues({...formValues, imageFiles: fileNames})
    
                // get array of file chunk objects, push to imageChunks array
                const file = await new Response(files[i]).arrayBuffer()
                const baseString = Buffer.from(file).toString('base64')
                const chunks = getChunks(files[i].name, baseString, 10000)
    
                fileChunks.push(chunks)
            }
    
            setImageChunks(null)
            setImageChunks([...fileChunks])
            console.log(imageChunks)
        }

Answer 1

You defined a class method that needs to be called on the class like A.abcd. But you initialize @x on an instance of A and also call an instance method by calling x.abcd.

Just remove the class << self from the class method definition

class << self
  def abcd
    puts @x
    puts 'something..'
  end
end

and change it to

def abcd
  puts @x
  puts 'something..'
end

Btw it is common in Ruby to indent code by just two whitespaces instead of four.